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Sample records for hydrocarbon hc emissions

  1. Motor vehicle fuel economy, the forgotten HC control stragegy. [Hydrocarbon (HC)

    Energy Technology Data Exchange (ETDEWEB)

    Deluchi, M.; Wang, Quanlu; Greene, D.L.

    1992-06-01

    Emissions of hydrocarbons from motor vehicles are recognized as major contributors to ozone pollution in urban areas. Petroleum-based motor fuels contain volatile organic compounds (VOC) which, together with oxides of nitrogen, promote the formation of ozone in the troposphere via complex photochemical reactions. VOC emissions from the tailpipe and evaporation from the fuel and engine systems of highway vehicles are believed to account for about 40% of total VOC emissions in any region. But motor fuels also generate emissions throughout the fuel cycle, from crude oil production to refining, storage, transportation, and handling, that can make significant contributions to the total inventory of VOC emissions. Many of these sources of emissions are directly related to the quantity of fuel produced and handled throughout the fuel cycle. It is, therefore, reasonable to expect that a reduction in total fuel throughput might result in a reduction of VOC emissions. In particular, reducing vehicle fuel consumption by increasing vehicle fuel economy should reduce total fuel throughput, thereby cutting total emissions of VOCS. In this report we identify the sources of VOC emissions throughout the motor fuel cycle, quantify them to the extent possible, and describe their dependence on automobile and light truck fuel economy.

  2. HC-PM COUPLING MODEL FOR PARTICULATE MATTER EMISSION OF DIESEL ENGINES

    Institute of Scientific and Technical Information of China (English)

    Tan Piqiang; Lu Jiaxiang; Deng Kangyao

    2005-01-01

    A rapid, phenomenological model that predicts particulate matter (PM) emission of diesel engines is developed and formulated. The model is a chemical equilibrium composition model, and is based on the formation mechanisms of PM and unburned hydrocarbon (HC) emissions of diesel engines. It can evaluate the emission concentration of PM via the emission concentration of HC. To validate the model, experiments are carried out in two research diesel engines. Comparisons of the model results with the experimental data show good agreement. The model can be used to evaluate the concentration of PM emission of diesel engines under lack of PM measuring instruments. In addition, the model is useful for computer simulations of diesel engines, as well as electronic control unit (ECU) designs for electronically controlled diesel engines.

  3. Systems and methods to mitigate NO.sub.x and HC emissions

    Science.gov (United States)

    Gupta, Aniket; Cunningham, Michael J.; Ruth, Michael J.; Chilumukuru, Krishna P.

    2017-06-14

    Systems and methods are provided for managing low temperature NO.sub.x and HC emissions, such as during a cold start of an internal combustion engine. The systems and methods include storing NO.sub.x and HC emissions at low temperatures and passively releasing and treating these emissions as the temperature of the exhaust system increases.

  4. Characterization of on-road CO, HC and NO emissions for petrol vehicle fleet in China city

    Institute of Scientific and Technical Information of China (English)

    GUO Hui; ZHANG Qing-yu; SHI Yao; WANG Da-hui; DING Shu-ying; YAN Sha-sha

    2006-01-01

    Vehicle emissions are a major source of air pollution in urban areas. The impact on urban air quality could be reduced if the trends of vehicle emissions are well understood. In the present study, the real-world emissions of vehicles were measured using a remote sensing system at five sites in Hangzhou, China from February 2004 to August 2005. More than 48000 valid gasoline powered vehicle emissions of carbon monoxide (CO), hydrocarbons (HC) and nitrogen oxide (NO) were measured. The results show that petrol vehicle fleet in Nangzhou has considerably high CO emissions, with the average emission concentration of 2.71%±0.02% , while HC and NO emissions are relatively lower, with the average emission concentration of (153.72± 1.16)× 10-6 and (233.53±1.80)× 10-6, respectively. Quintile analysis of both average emission concentration and total amount emissions by model year suggests that in-use emission differences between well maintained and badly maintained vehicles are larger than the age-dependent deterioration of emissions. In addition, relatively new high polluting vehicles are the greatest contributors to fleet emissions with, for example, 46.55% of carbon monoxide fleet emissions being produced by the top quintile high emitting vehicles from model years 2000~2004. Therefore, fleet emissions could be significantly reduced if new highly polluting vehicles were subject to effective emissions testing followed by appropriate remedial action.

  5. Mathematical Modeling of HC Emissions Released by Oil Film for Gasoline and Alcohol Fuels

    Directory of Open Access Journals (Sweden)

    M. İhsan KARAMANGİL

    2013-04-01

    Full Text Available Oil film on cylinder liner has been suggested as a major source of engine-out hydrocarbon emissions. So in the present study, the rate of absorption/desorption of the fuel in the oil film has been investigated numerically in a spark ignition engine by using gasoline, ethanol and methanol fuels. To aim this purpose, a thermodynamic cycle model has been developed and then a mathematical modeling for the rate of absorption/desorption of the fuel in the oil film has been developed and adapted for this thermodynamic cycle model.It was seen that the absorption/desorption mechanism of ethanol and methanol into the oil film were lower than gasoline. It was determined that the most dominant parameter of this difference was Henry’s constant, which was related to solubility. As interaction time of oil filmfuel vapor was longer at low engine speeds, the quantities of HC absorbed/desorbed increased. The quantities of HC absorbed/desorbed increased with increasing inlet pressure and compression ratio

  6. Emission factors of air pollutants from CNG-gasoline bi-fuel vehicles: Part II. CO, HC and NOx.

    Science.gov (United States)

    Huang, Xiaoyan; Wang, Yang; Xing, Zhenyu; Du, Ke

    2016-09-15

    The estimation of emission factors (EFs) is the basis of accurate emission inventory. However, the EFs of air pollutants for motor vehicles vary under different operating conditions, which will cause uncertainty in developing emission inventory. Natural gas (NG), considered as a "cleaner" fuel than gasoline, is increasingly being used to reduce combustion emissions. However, information is scarce about how much emission reduction can be achieved by motor vehicles burning NG (NGVs) under real road driving conditions, which is necessary for evaluating the environmental benefits for NGVs. Here, online, in situ measurements of the emissions from nine bi-fuel vehicles were conducted under different operating conditions on the real road. A comparative study was performed for the EFs of black carbon (BC), carbon monoxide (CO), hydrocarbons (HCs) and nitrogen oxides (NOx) for each operating condition when the vehicles using gasoline and compressed NG (CNG) as fuel. BC EFs were reported in part I. The part II in this paper series reports the influence of operating conditions and fuel types on the EFs of CO, HC and NOx. Fuel-based EFs of CO showed good correlations with speed when burning CNG and gasoline. The correlation between fuel-based HC EFs and speed was relatively weak whether burning CNG or gasoline. The fuel-based NOx EFs moderately correlated with speed when burning CNG, but weakly correlated with gasoline. As for HC, the mileage-based EFs of gasoline vehicles are 2.39-12.59 times higher than those of CNG vehicles. The mileage-based NOx EFs of CNG vehicles are slightly higher than those of gasoline vehicles. These results would facilitate a detailed analysis of the environmental benefits for replacing gasoline with CNG in light duty vehicles. Copyright © 2016 Elsevier B.V. All rights reserved.

  7. Emissions of CO2, CO, NOx, HC, PM, HFC-134a, N2O and CH4 from the global light duty vehicle fleet

    Directory of Open Access Journals (Sweden)

    Timothy J. Wallington

    2008-04-01

    Full Text Available Vehicles emit carbon dioxide (CO2, carbon monoxide (CO, nitrogen oxides (NOx, hydrocarbons (HC, particulate matter (PM, hydrofluorocarbon 134a (HFC-134a, methane (CH4, and nitrous oxide (N2O. An understanding of these emissions is needed in discussions of climate change and local air pollution issues. To facilitate such discussions an overview of past, present, and likely future emissions from light duty vehicles is presented. Emission control technologies have reduced the emissions of CO, VOCs, PM, HFC-134a, CH4, and N2O from modern vehicles to very low levels.

  8. 33 CFR 157.166 - Hydrocarbon emissions.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Hydrocarbon emissions. 157.166... Crude Oil Washing (COW) System on Tank Vessels Cow Operations § 157.166 Hydrocarbon emissions. If the... ballasted in that port the hydrocarbon vapors in each tank are contained by a means under § 157.132....

  9. SeaMon-HC Buoy. A specific real-time-lightweight-moored platform as a tool for fast hydrocarbon detection

    Science.gov (United States)

    Barrera, C.; Rueda, M. J.; Moran, R.; Llerandi, C.; Llinas, O.

    2009-04-01

    The present paper-work describes the design, last development stages and the derived results from a specific buoy platform for fast hydrocarbon detection in seawater. Under the name of SeaMon-HC, (Patent No. P200302219/8) the buoy represents a very chief tool for coastal monitoring, mainly surrounding areas with a high oil-spill risk level, like harbours, off-shore fish farming, beaches and so on. Nowadays, the Macaronesian area has nine units working in real-time, under the frame of the Red ACOMAR Network. The main innovative aspect from this buoy is the detection system. It's based in polymer technology, working as a resistance, who increase its value when the pollutant on water surface is detected. The response time from the sensor is a direct function of the hydrocarbon volatility level. For hydrocarbons with high volatility levels (like petrol), the sensor needs less time (around 3 minutes) than others with less volatility such as oils. SeaMon-HC is an autonomous, modular, reusable and a very low-cost development integrated by four subsystems (SS): SS-Flotation (different materials and shapes available); SS-Sensors (hydrocarbon detector and additional sensors -up to 15-, to solve specific sensor configuration requirements); SS-Power Supply (equipped in its basic configuration with a couple of solar modules and two 12V batteries) and the SS-Communication (based on a RF or GSM/GPRS modem technology, with a selectable communication frequency). All SeaMon-HC units, as well the rest of the ODAS buoys who joint together the Red ACOMAR Network, works in real-time, sending the collected information to the control centre that manages the communications, providing data, in a useful form (as a web site), to diverse socio-economic important sectors which make an exhaustive use of the littoral in the Macaronesian region. The access to the information by the users is done through a specific GIS software application.

  10. Performance and energy saving analysis of a refrigerator using hydrocarbon mixture (HC-R134a) as working fluid

    Science.gov (United States)

    Mohtar, M. N.; Nasution, H.; Aziz, A. A.

    2015-12-01

    The use of hydrocarbon mixture as a working fluid in a refrigerator system is rarely explored. Almost all domestic refrigerators use hydroflourocarbon R134a (HFC-R134a) as refrigerants. In this study, hydrocarbon gas (HC-R134a) is used as the alternative refrigerant to replace HFC-R134a. It has a composition of R290 (56%), R600a (54.39%) and additive (0.1%wt) blended for the trials. The experiments were conducted with 105 g and 52.5 g refrigerant mass charge, subjected to internal heat load of 0, 1, 2, 3 and 4 kg respectively. The study investigates the coefficient of performance of the refrigerator (COPR) and energy consumption. The results show that the use of HC-R134a as the replaceable refrigerant can save energy ranging from 2.04% to 7.09%, as compared to the conventional HFC-R134a refrigerant. Naturally, the COPR improvement and temperature distribution using HC-R134a are much better than HFC-R134a

  11. Luminous HC3N line emission in NGC4418 - buried AGN or nascent starburst?

    CERN Document Server

    Aalto, S; Martin, S

    2007-01-01

    IRAM 30m observations reveal that the deeply obscured IR-luminous galaxy NGC4418 has a rich molecular chemistry - including unusually luminous HC3N line emission. We furthermore detect: ortho-H2CO 2-1, 3-2; CN 1-0, 2-1; HCO+, 1-0. 3-2, HCN 3-2, HNC 1-0, 3-2 (and tentatively OCS 12-11). The HCN, HCO+, H2CO and CN line emission can be fitted to densities of n=5 x 10E4 - 10E5 cm-3 and gas temperatures Tk=80-150 K. Both HNC and HC3N are, however, significantly more excited than the other species which requires higher gas densities - or radiative excitation through e.g. mid-IR pumping. The HCN line intensity is fainter than that of HCO+ and HNC for the 3-2 transition, in contrast to previous findings for the 1-0 lines where the HCN emission is the most luminous. We tentatively suggest that the observed molecular line emission is consistent with a young starburst, where the emission can be understood as emerging from dense, warm gas with an additional PDR component. We find that X-ray chemistry is not required to e...

  12. 40 CFR 52.987 - Control of hydrocarbon emissions.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 3 2010-07-01 2010-07-01 false Control of hydrocarbon emissions. 52... (CONTINUED) APPROVAL AND PROMULGATION OF IMPLEMENTATION PLANS Louisiana § 52.987 Control of hydrocarbon... compliance date of January 1, 1980. This shall result in an estimated hydrocarbon emission reduction of...

  13. Combining GTL fuel, reformed EGR and HC-SCR aftertreatment system to reduce diesel NO{sub x} emissions. A statistical approach

    Energy Technology Data Exchange (ETDEWEB)

    Rodriguez-Fernandez, J. [E.T.S. Ingenieros Industriales, Dpto. Mecanica Aplicada e Ingenieria de Proyectos, Universidad de Castilla-La Mancha, 13071 Ciudad Real (Spain); Tsolakis, A. [School of Mechanical Engineering, University of Birmingham, Birmingham B15 2TT (United Kingdom); Cracknell, R.F.; Clark, R.H. [Shell Global Solutions, Cheshire Innovation Park, Chester CH1 3SH (United Kingdom)

    2009-03-15

    An ultra-low sulphur diesel (ULSD) fuel and a synthetic gas-to-liquid (GTL) fuel, besides different types of standard and reformed EGR, were evaluated in a single-cylinder, direct injection, diesel engine equipped with hydrocarbon-selective catalytic reduction (HC-SCR) aftertreatment system. The results obtained were statistically analysed (at 95% statistical significance) to identify the most significant factors that affect NO{sub x} emissions and to search for the optimum operation conditions in order to minimize these emissions. For that purpose, a fully crossed factorial experimental design was used, including two different engine speeds (1200 and 1500 rpm), two engine loads (25% and 50%), and four EGR/REGR ratios (0%, 10%, 20% and 30%) resulting in almost one hundred tests. An optimal combination of fuel type, REGR type and REGR ratio was proved to reduce around 89-95% of the reference NO{sub x} emissions. In general, at 25% engine load GTL fuelling combined with the reformed EGR with the highest hydrogen content was found the most desirable, as the hydrogen sharply increased the NO{sub x} conversion in the SCR catalyst. Differently, at 50% load standard EGR was sufficient to reach high NO{sub x} reductions. These findings may be used for the implementation of a system on-board capable to switch from EGR to REGR, which will help engine manufacturers to meet the future emission regulations. (author)

  14. Characterization of polycyclic aromatic hydrocarbon emissions in the particulate phase from burning incenses with various atomic hydrogen/carbon ratios

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Tzu-Ting, E-mail: d89844001@ntu.edu.tw [Department of Environmental Engineering and Health, Yuanpei University, No. 306, Yuanpei St., Hsin Chu, 300, Taiwan (China); Lin, Shaw-Tao [Department of Applied Chemistry, Providence University, 200 Chung-Chi Rd., Salu Dist., Taichung City 43301, Taiwan (China); Lin, Tser-Sheng [Department of Safety, Health, and Environmental Engineering, National United University, 2 Lien Da, Maioli, 360, Taiwan (China); Hong, Wei-Lun [Department of Environmental Engineering and Health, Yuanpei University, No. 306, Yuanpei St., Hsin Chu, 300, Taiwan (China)

    2012-01-01

    Polycyclic aromatic hydrocarbons in the particulate phase generated from burning various incense was investigated by a gas chromatography/mass spectrometry. Among the used incenses, the atomic H/C ratio ranged from 0.51 to 1.69, yielding the emission factor ranges for total particulate mass and PAHs of 4.19-82.16 mg/g and 1.20-9.50 {mu}g/g, respectively. The atomic H/C ratio of the incense was the key factor affecting particulate mass and the PAHs emission factors. Both the maximum emission factor and the slowest burning rate appear at the H/C ratio of 1.57. The concentrations of the four-ring PAHs predominated and the major species among the 16 PAHs were fluoranthene, phenanthrene, pyrene, and chrysene for most incense types. The benzo[a]pyrene, benzo[a]anthracene, benzo[b]fluoranthene, and dibenzo[a,h]anthracene accounted for 87.08-93.47% of the total toxic equivalency emission factor. - Highlights: Black-Right-Pointing-Pointer The atomic H/C ratio of incense was the key factor affecting PAHs emission factors. Black-Right-Pointing-Pointer Burning incense with lower atomic H/C ratio minimized the production of total PAHs. Black-Right-Pointing-Pointer The BaP, BaA, BbF, and DBA accounted for 87.08-93.47% of the TEQ emission factor. Black-Right-Pointing-Pointer Special PAH ratios were regarded as characteristic ratios for burning incense.

  15. Study of liquid fuel transport in a small carburetted engine in the context of cold-start HC emission control

    Indian Academy of Sciences (India)

    Sumit Tewari; T N C Anand; M P Nishikant; R V Ravikrishna

    2014-06-01

    In the present study, a detailed visualization of the transport of fuel film has been performed in a small carburetted engine with a transparent manifold at the exit of the carburettor. The presence of fuel film is observed significantly on the lower half of the manifold at idling, while at load conditions, the film is found to be distributed all throughout the manifold walls. Quantitative measurement of the fuel film in a specially-designed manifold of square cross section has also been performed using the planar laser-induced fluorescence (PLIF) technique. The measured fuel film thickness is observed to be of the order of 1 mm at idling, and in the range of 0.1 to 0.4 mm over the range of load and speed studied. These engine studies are complemented by experiments conducted in a carburettor rig to study the state of the fuel exiting the carburettor. Laser-based Particle/Droplet Image Analysis (PDIA) technique is used to identify fuel droplets and ligaments and estimate droplet diameters. At a throttle position corresponding to idling, the fuel exiting the carburettor is found to consist of very fine droplets of size less than 15 m and large fuel ligaments associated with length scales of the order of 500 m and higher. For a constant pressure difference across the carburettor, the fuel consists of droplets with an SMD of the order of 30 m. Also, the effect of liquid fuel film on the cold start HC emissions is studied. Based on the understanding obtained from these studies, strategies such as manifold heating and varying carburettor main jet nozzle diameter are implemented. These are observed to reduce emissions under both idling and varying load conditions.

  16. Optimization of gasoline hydrocarbon compositions for reducing exhaust emissions.

    Science.gov (United States)

    Shen, Yitao; Shuai, Shijin; Wang, Jianxin; Xiao, Jianhua

    2009-01-01

    Effects of hydrocarbon compositions on raw exhaust emissions and combustion processes were studied on an engine test bench. The optimization of gasoline hydrocarbon composition was discussed. As olefins content increased from 10.0% to 25.0% in volume, the combustion duration was shortened by about 2 degree crank angle (degrees CA), and the engine-out THC emission was reduced by about 15%. On the other hand, as aromatics content changed from 35.0% to 45.0%, the engine-out NOx emissions increased by 4%. An increment in olefins content resulted in a slight increase in engine-out CO emission, while the aromatics content had little effect on engine-out total hydrocarbon (THC) and CO emissions. Over the new European driving cycle (NEDC), the THC, NOx and CO emissions of fuel with 25.0% olefins and 35.0% aromatics were about 45%, 21% and 19% lower than those of fuel with 10.0% olefins and 40.0% aromatics, respectively. The optimized gasoline compositions for new engines and new vehicles have low aromatics and high olefins contents.

  17. Piston ring lubrication and hydrocarbon emissions from internal combustion engines

    Energy Technology Data Exchange (ETDEWEB)

    Froelund, K.

    1997-11-01

    Is it the intention with this project to improve the existing hydrocarbon emission model at the Institute by combining it with a model for predicting the piston ring lubrication. The piston ring lubrication model should be experimentally verified to ensure the validity of the model. The following items were the objectives of the current study: Develop a piston ring lubrication model. This implies the development of a ring-pack gas flow model; Examine the response of the piston ring lubrication model to changing engineer conditions. Especially, it would be interesting to look at the engine warm-up phase since this is the phase where the engine-out emissions are highest and where the commonly used three way catalyst is not capable of converting the engine-out emissions, thereby leading the engine-out emissions directly out in to the environment with the exhaust gases; In order to verify the piston ring lubrication model the lubricant distribution on the cylinder liner should be investigated experimentally. Here again it would be of great interesting to look at the engine warm-up phase; The piston ring lubrication model should be adjusted for application together with the new hydrocarbon emission model for SI-engines at the Institute in order to increase the accuracy of the latter; The piston ring lubrication model could be used for describing the transport of PAH`s in diesel engines. (EG)

  18. Hydrocarbon Emission Rings in Protoplanetary Disks Induced by Dust Evolution

    Science.gov (United States)

    Bergin, Edwin A.; Du, Fujun; Cleeves, L. Ilsedore; Blake, G. A.; Schwarz, K.; Visser, R.; Zhang, K.

    2016-11-01

    We report observations of resolved C2H emission rings within the gas-rich protoplanetary disks of TW Hya and DM Tau using the Atacama Large Millimeter Array. In each case the emission ring is found to arise at the edge of the observable disk of millimeter-sized grains (pebbles) traced by submillimeter-wave continuum emission. In addition, we detect a C3H2 emission ring with an identical spatial distribution to C2H in the TW Hya disk. This suggests that these are hydrocarbon rings (i.e., not limited to C2H). Using a detailed thermo-chemical model we show that reproducing the emission from C2H requires a strong UV field and C/O > 1 in the upper disk atmosphere and outer disk, beyond the edge of the pebble disk. This naturally arises in a disk where the ice-coated dust mass is spatially stratified due to the combined effects of coagulation, gravitational settling and drift. This stratification causes the disk surface and outer disk to have a greater permeability to UV photons. Furthermore the concentration of ices that transport key volatile carriers of oxygen and carbon in the midplane, along with photochemical erosion of CO, leads to an elemental C/O ratio that exceeds unity in the UV-dominated disk. Thus the motions of the grains, and not the gas, lead to a rich hydrocarbon chemistry in disk surface layers and in the outer disk midplane.

  19. An Emission Inventory of Polycyclic Aromatic Hydrocarbons in China

    Science.gov (United States)

    Mu, Xilong; Zhu, Xianlei; Wang, Xuesong

    2015-04-01

    Polycyclic Aromatic Hydrocarbons (PAHs) are among the most dangerous compounds due to their high carcinogenic and mutagenic character. Emission inventory provides the primary data to account for the sources of ambient PAHs and server as a necessary database for effective PAHs pollution control. China is experiencing fast economic growth and large energy consumption, which might result in a large amount of PAHs anthropogenic emissions. Therefore, based on the previous studies and combined recently field emission measurements as well as socio-economic activity data, the development of a nationwide PAHs emission inventory is needed. In this work, the emission inventory of 16 PAHs listed as U.S. Environmental Protection Agency priority pollutants in China in the year 2012 is compiled. The emission amounts of PAHs were estimated as annual rates of emission-related activities multiplied by respective emission factors. The activities such as fuel consumption, including fossil fuel and biofuel, and socio-economic statistics were obtained from yearbook released by Chinese central government and/or provincial governments, as well as related industry reports. Emission factors were derived from the related literature. Recently reported emission factors from local measurements were used. The total emissions of PAHs were 120611 ton in 2012. In China, PAHs were emitted predominantly from domestic combustion of coal and biofuel, coking industry and motor vehicles, accounting for 72% of the total amount. PAHs emission profiles were significantly different between China and the other countries. The emission profile in China featured a relatively higher portion of high molecular weight species with carcinogenic potential due to large contributions of domestic combustion and coking industry. Domestic combustion of straw, coal and firewood emitted 19464 ton, 8831 ton, and 5062 ton of PAHs, respectively, which were much higher than those in other countries. Emission per capita showed

  20. Hydrocarbons emissions from Cerro Prieto Geothermal Power Plant, Mexico

    Science.gov (United States)

    Navarro, Karina; Navarro-González, Rafael; de la Rosa, José; Peralta, Oscar; Castro, Telma; Imaz, Mireya

    2014-05-01

    One of the most important environmental issues related to the use of geothermal fluids to generate electricity is the emission of non-condensable gases to the atmosphere. Mexico has one of the largest geothermal plants in the world. The facility is located at Cerro Prieto, Baja California, roughly 30 km south of Mexicali and the international boundary between Mexico and United States. The Cerro Prieto power plant has 13 units grouped on four individual powerhouses. Gas samples from 9 units of the four powerhouses were collected during 4 campaigns conducted in May-July, 2010, February, 2012, December, 2012, and May, 2013. Gas samples from the stacks were collected in 1000 ml Pyrex round flasks with Teflon stopcocks, and analyzed by gas chromatography-mass spectrometry. Methane was the most abundant aliphatic hydrocarbon, with a concentration that ranged from less than 1% up to 3.5% of the total gas mixture. Normal alkanes represented the second most abundant species, and displayed a decreasing abundance with increasing carbon number in the homologous series. Isoalkanes were also present as isobutane and isopentane. Cycloalkanes occurring as cyclopentane and cyclohexane, were detected only at trace level. Unsaturated hydrocarbons (alkenes and alkynes) were not detected. Benzene was detected at levels ranging from less than 1% up to 3.4% of the total gas mixture. Other aromatic hydrocarbons detected were toluene, and xylenes, and were present at lower concentrations (

  1. Hydrocarbon emission rings in protoplanetary disks induced by dust evolution

    CERN Document Server

    Bergin, Edwin A; Cleeves, L Ilsedore; Blake, Geoffrey A; Schwarz, Kamber; Visser, Ruud; Zhang, Ke

    2016-01-01

    We report observations of resolved C2H emission rings within the gas-rich protoplanetary disks of TW Hya and DM Tau using the Atacama Large Millimeter Array (ALMA). In each case the emission ring is found to arise at the edge of the observable disk of mm-sized grains (pebbles) traced by (sub)mm-wave continuum emission. In addition, we detect a C3H2 emission ring with an identical spatial distribution to C2H in the TW Hya disk. This suggests that these are hydrocarbon rings (i.e. not limited to C2H). Using a detailed thermo-chemical model we show that reproducing the emission from C2H requires a strong UV field and C/O > 1 in the upper disk atmosphere and outer disk, beyond the edge of the pebble disk. This naturally arises in a disk where the ice-coated dust mass is spatially stratified due to the combined effects of coagulation, gravitational settling and drift. This stratification causes the disk surface and outer disk to have a greater permeability to UV photons. Furthermore the concentration of ices that ...

  2. Emission of polycyclic aromatic hydrocarbons from gasohol and ethanol vehicles

    Science.gov (United States)

    de Abrantes, Rui; Vicente de Assunção, João; Pesquero, Célia Regina; Bruns, Roy Edward; Nóbrega, Raimundo Paiva

    The exhaust emission of the polycyclic aromatic hydrocarbons (PAHs) considered toxic to human health were investigated on two spark ignition light duty vehicles, one being gasohol (Gasohol, in Brazil, is the generic denomination for mixtures of pure gasoline plus 20-25% of anhydrous ethyl alcohol fuel (AEAF).)-fuelled and the other a flexible-fuel vehicle fuelled with hydrated ethanol. The influence of fuel type and quality, aged lubricant oil type and use of fuel additives on the formation of these compounds was tested using standardized tests identical to US FTP-75 cycle. PAH sampling and chemical analysis followed the basic recommendations of method TO-13 (United States. Environmental Protection Agency, 1999. Compendium Method TO-13A - Determination of polycyclic Aromatic hydrocarbons (PAH) in Ambient Air Using Gas Chromatography/Mass Spectrometry (CG/MS). Center for environmental research information, Cincinnati, p. 78), with the necessary modification for this particular application. Results showed that the total PAH emission factor varied from 41.9 μg km -1 to 612 μg km -1 in the gasohol vehicle, and from 11.7 μg km -1 to 27.4 μg km -1 in the ethanol-fuelled vehicle, a significant difference in favor of the ethanol vehicle. Generally, emission of light molecular weight PAHs was predominant, while high molecular weights PAHs were not detected. In terms of benzo( a)pyrene toxicity equivalence, emission factors varied from 0.00984 μg TEQ km -1 to 4.61 μg TEQ km -1 for the gasohol vehicle and from 0.0117 μg TEQ km -1 to 0.0218 μg TEQ km -1 in the ethanol vehicle. For the gasohol vehicle, results showed that the use of fuel additive causes a significant increase in the emission of naphthalene and phenanthrene at a confidence level of 90% or higher; the use of rubber solvent on gasohol showed a reduction in the emission of naphthalene and phenanthrene at the same confidence level; the use of synthetic oil instead of mineral oil also contributed

  3. Biogenic nonmethane hydrocarbon emissions estimated from tethered balloon observations

    Science.gov (United States)

    Davis, K. J.; Lenschow, D. H.; Zimmerman, P. R.

    1994-01-01

    A new technique for estimating surface fluxes of trace gases, the mixed-layer gradient technique, is used to calculate isoprene and terpene emissions from forests. The technique is applied to tethered balloon measurements made over the Amazon forest and a pine-oak forest in Alabama at altitudes up to 300 m. The observations were made during the dry season Amazon Boundary Layer Experiment (ABLE 2A) and the Rural Oxidants in the Southern Environment 1990 experiment (ROSE I). Results from large eddy simulations of scalar transport in the clear convective boundary layer are used to infer fluxes from the balloon profiles. Profiles from the Amazon give a mean daytime emission of 3630 +/- 1400 micrograms isoprene sq m/h, where the uncertainty represents the standard deviation of the mean of eight flux estimates. Twenty profiles from Alabama give emissions of 4470 +/- 3300 micrograms isoprene sq m/h, 1740 +/- 1060 micrograms alpha-pinene sq m/h, and 790 +/- 560 micrograms beta-pinene sq m/h, respectively. These results are in agreement with emissions derived from chemical budgets. The emissions may be overestimated because of uncertainty about how to incorporate the effects of the canopy on the mixed-layer gradients. The large variability in these emission estimates is probably due to the relatively short sampling times of the balloon profiles, though spatially heterogeneous emissions may also play a role. Fluxes derived using this technique are representative of an upwind footprint of several kilometers and are independent of hydrocarbon oxidation rate and mean advection.

  4. Federal Air Pollutant Emission Regulations and Preliminary Estimates of Potential-to-Emit from Biorefineries. Pathway #1: Dilute-Acid and Enzymatic Deconstruction of Biomass-to-Sugars and Biological Conversion of Sugars-to-Hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yimin [National Renewable Energy Lab. (NREL), Golden, CO (United States); Bhatt, Arpit [National Renewable Energy Lab. (NREL), Golden, CO (United States); Heath, Garvin [National Renewable Energy Lab. (NREL), Golden, CO (United States); Thomas, Mae [Eastern Research Group, Lexington, MA (United States); Renzaglia, Jason [Eastern Research Group, Lexington, MA (United States)

    2016-02-01

    Biorefineries are subject to environmental laws, including complex air quality regulations that aim to protect and improve the quality of the air. These regulations govern the amount of certain types of air pollutants that can be emitted from different types of emission sources. To determine which federal air emission regulations potentially apply to the sugars-to-hydrocarbon (HC) biorefinery, we first identified the types of regulated air pollutants emitted to the ambient environment by the biorefinery or from specific equipment. Once the regulated air pollutants are identified, we review the applicability criteria of each federal air regulation to determine whether the sugars-to-HC biorefinery or specific equipment is subject to it. We then estimate the potential-to-emit of pollutants likely to be emitted from the sugars-to-HC biorefinery to understand the air permitting requirements.

  5. Description and History of the MOBILE Highway Vehicle Emission Factor Model

    Science.gov (United States)

    MOBILE is an EPA model for estimating pollution from highway vehicles. It has been superseded by the Motor Vehicle Emission Simulator (MOVES). MOBILE calculates emissions of hydrocarbons (HC), oxides of nitrogen (NOx) and carbon monoxide (CO).

  6. Frozen Hydrocarbon Particles of Cometary Halos as Carriers of Unidentified Emissions

    Indian Academy of Sciences (India)

    Irakli Simonia

    2005-12-01

    The possible nature of unidentified cometary emissions is under discussion. We propose a new model of the ice particles in cometary halos as a mixture of frozen polycyclic aromatic hydrocarbons and acyclic hydrocarbons.We describe principal properties of frozen hydrocarbon particles (FHPs) and suggest interpreting some of the unidentified cometary emission lines as the photoluminescence of FHPs. The results of comparative analysis are present.

  7. Emissions of non-methane hydrocarbons from cars in China

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    This study investigated the exhaust emission of non-methane hydrocarbons(NMHCs) from cars in China at the Beijing driving cycle on the chassis dynamometer.The emission factor average of NMHCs was 0.9 g/km,which was over twice that from the Australian car fleet and 2-4 times that of the American car emission in the 1990s-2000s.The emission profile of Beijing cars showed higher fractions of aromatics and C4?C7 HCs,and lower percentages of C2?C3 HCs,compared with those of the US car fleet.The average ratio of benzene/toluene for cars tested was 0.5,the average benzene/toluene/ethyl benzene/xylenes(BTEX) ratios were 1/2.2/0.1/1.8,which were consistent with those of the Tanyugou tunnel located in the suburb of Beijing.α-pinene and β-pinene were detected from the exhaust gas on dynamometer for the first time,and had likely similar exhaust emission characteristics with C2?C3 HCs and styrene,giving an evidence that air pinenes may be related to human activities.Isoprene was also detected directly.These observations suggest that the procedure regarding pinenes and isoprene as coming from biologic sources of VOCs in the atmosphere should be applied with great care,especially in the core of the big city like Beijing.The specific reactivity of NMHCs was higher than that of cars of US,and the specific reactivity of volatile aromatic compounds was higher than that of the US SPECIATE database.

  8. The application of forest classification from Landsat data as a basis for natural hydrocarbon emission estimation and photochemical oxidant model simulations in southeastern Virginia

    Science.gov (United States)

    Salop, J.; Wakelyn, N. T.; Levy, G. F.; Middleton, W. M.; Gervin, J. C.

    1983-01-01

    The possible contribution by natural hydrocarbon emissions to the total ozone budget recorded in the Tidewater region of southeastern Virginia during the height of the summer period was examined. Natural sources investigated were limited to the primary HC emitters and most prevalent natural vegetation, the forests. Three types and their areal coverage were determined for Region VI of the Virginia State Air Pollution Control Board using remotely sensed data from Landsat, a NASA experimental earth resources satellite. Emission factors appropriate to the specific types (coniferous 0.24 x 10 to the 13th, mixed 0.63 x 10 to the 13th, deciduous 1.92 x 10 to the 13th, microgram/h), derived from contemporary procedures, were applied to produce an overall regional emission rate of 2.79 x 10 to the 13th microgram/h for natural non-methane hydrocarbons (NMHC). This rate was used with estimates of the anthropogenic NO(x) and NMHC loading, as input into a photochemical box model. Additional HC loading on the order of that estimated to be produced by the natural forest communities was required in order to reach certain measured summer peak ozone levels as the computer simulation was unable to account for the measured episodic levels on the basis of the anthropogenic inventory alone.

  9. C2-C10 hydrocarbon emissions from a boreal wetland and forest floor

    Directory of Open Access Journals (Sweden)

    H. Hellén

    2006-01-01

    Full Text Available Emissions of various C2-C10 hydrocarbons (VOCs and halogenated hydrocarbons (VHOCs from a boreal wetland and a Scots pine forest floor in south-western Finland were measured by the static chamber technique. Isoprene was the main non-methane hydrocarbon emitted by the wetland, but small emissions of ethene, propane, propene, 1-butene, 2-methylpropene, butane, pentane and hexane were also detected. The isoprene emission from the wetland was observed to follow the commonly-used isoprene emission algorithm. The mean emission potential of isoprene was 224 µg m-2 h-1 for the whole season. This is lower than the emission potentials published earlier; that is probably at least partly due to the cold and cloudy weather during the measurements. No emissions were detected of monoterpenes or halogenated hydrocarbons from the wetland. The highest hydrocarbon emissions from the Scots pine forest floor were measured in spring and autumn. However, only a few measurements were conducted during summer. The main compounds emitted were monoterpenes. Isoprene emissions were negligible. The total monoterpene emission rates varied from zero to 373 µg m-2 h-1. The results indicated that decaying plant litter may be the source for these emissions. Small emissions of chloroform (100-800 ng m-2 h-1, ethene, propane, propene, 2-methylpropene, cis-2-butene, pentane, hexane and heptane were detected. Comparison with Scots pine emissions showed that the forest floor may be an important monoterpene source, especially in spring.

  10. Emissions of polycyclic aromatic hydrocarbons from coking industries in China

    Institute of Scientific and Technical Information of China (English)

    Ling Mu; Lin Peng; Junji Cao; Qiusheng He; Fan Li; Jianqiang Zhang; Xiaofeng Liu

    2013-01-01

    This study set out to assess the characteristics of polycyclic aromatic hydrocarbon (PAH) emission from coking industries,with field samplings conducted at four typical coke plants.For each selected plant,stack flue gas samples were collected during processes that included charging coal into the ovens (CC),pushing coke (PC) and the combustion of coke-oven gas (CG).Sixteen individual PAHs on the US EPA priority list were analyzed by gas chromatography/mass spectrometry (GC/MS).Results showed that the total PAH concentrations in the flue gas ranged from 45.776 to 414.874 μg/m3,with the highest emission level for CC (359.545 μg/m3).The concentration of PAH emitted from the CC process in CP1 (stamp charging) was lower than that from CP3 and CP4 (top charging).Low-molecular-weight PAHs (i.e.,two-to three-ring PAHs) were predominant contributors to the total PAH contents,and Nap,AcPy,Flu,PhA,and AnT were found to be the most abundant ones.Total BaPeq concentrations for CC (2.248 iμg/m3) were higher than those for PC (1.838 μg/m3) and CG (1.082 μg/m3),and DbA was an important contributor to carcinogenic risk as BaP in emissions from coking processes.Particulate PAH accounted for more than 20% of the total BaPeq concentrations,which were significantly higher than the corresponding contributions to the total PAH mass concentration (5%).Both particulate and gaseous PAH should be taken into consideration when the potential toxicity risk of PAH pollution during coking processes is assessed.The mean total-PAH emission factors were 346.132 and 93.173 μg/kg for CC and PC,respectively.

  11. Characterization of polycyclic aromatic hydrocarbon emissions in the particulate and gas phase from smoldering mosquito coils containing various atomic hydrogen/carbon ratios

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Tzu-Ting, E-mail: d89844001@ntu.edu.tw [Department of Environmental Engineering and Health, Yuanpei University, No. 306, Yuanpei St., Hsin Chu 30015, Taiwan (China); Lin, Shaw-Tao [Department of Applied Chemistry, Providence University, No. 200 Chung-Chi Rd., Salu Dist., Taichung City 43301, Taiwan (China); Lin, Tser-Sheng [Department of Safety, Health, and Environmental Engineering, National United University, 2 Lien Da, Maioli 360, Taiwan (China); Chung, Hua-Yi [Department of Environmental Engineering and Health, Yuanpei University, No. 306, Yuanpei St., Hsin Chu 30015, Taiwan (China)

    2015-02-15

    The polycyclic aromatic hydrocarbon emissions in particulate and gas phases generated from smoldering mosquito coils containing various atomic H/C ratios were examined. Five types of mosquito coils were burned in a test chamber with a total airflow rate of 8.0 L/min at a constant relative humidity and temperature. The concentrations of individual PAHs were determined using the GC/MS technique. Among the used mosquito coils, the atomic H/C ratio ranged from 1.23 to 1.57, yielding total mass, gaseous, and particulate PAH emission factors of 28.17–78.72 mg/g, 26,139.80–35,932.98 and 5735.22–13,431.51 ng/g, respectively. The various partitions of PAHs in the gaseous and particulate phases were in the ranges, 70.26–83.70% and 16.30–29.74% for the utilized mosquito coils. The carcinogenic potency of PAH emissions in the particulate phase (203.82–797.76 ng/g) was approximately 6.92–25.08 times higher than that of the gaseous phase (26.27–36.07 ng/g). Based on the analyses of PAH emissions, mosquito coils containing the lowest H/C ratio, a low oxygen level, and additional additives (i.e., CaCO{sub 3}) are recommended for minimizing the production of total PAH emission factors and carcinogenic potency. - Highlights: • PAHs emissions are influenced by mosquito coils containing various atomic H/C ratios. • The PAHs generated by burning mosquito coils mainly occur in the gaseous phase. • Total TEQ emission factors of PAHs mainly consisted of the particulate phase (> 87%). • The BaP and BaA accounted for 71.13–77.28% of the total TEQ emission factors. • Special PAH ratios were regarded as characteristic ratios for burning mosquito coil.

  12. H.C. Andersen

    DEFF Research Database (Denmark)

    Nissen, Mogens Rostgaard

    2008-01-01

    "Mit Liv er et smukt Eventyr, saa rigt og lyksaligt!" Sådan beskrev H.C. Andersens sit eget liv. Det overgik næsten indholdet af hans egne eventyr. Født i fattigdom og social nød, men kæmpede sig op og døde berømt og feteret 70 år senere. H.C. Andersen er Danmarks bedst kendte forfatter. Især hans...

  13. Theoretical modeling of infrared emission from neutral and charged polycyclic aromatic hydrocarbons. II.

    NARCIS (Netherlands)

    Bakes, ELO; Tielens, AGGM; Bauschlicher, CW; Hudgins, DM; Allamandola, LJ

    2001-01-01

    The nature of the carriers of the interstellar infrared (IR) emission features between 3.3 and 12.7 mum is complex. We must consider emission from a family of polycyclic aromatic hydrocarbons (PAHs) in a multiplicity of cationic charge states (+1, +2, +3, and so on), along with neutral and anionic P

  14. Investigations of the causes of hydrocarbon emissions in spark ignition engines with homogeneous charge compression ignition (HCCI). A report of the Institute for Internal Combustion Engines and Automotive Engineering, TU Vienna (IVK); Untersuchung der Ursachen fuer Kohlenwasserstoff-Emissionen beim Ottomotor mit homogener Selbstzuendung (HCCI). Bericht des Instituts fuer Verbrennungskraftmaschinen und Kraftfahrzeugbau derTechnischen Universitaet Wien (IVK)

    Energy Technology Data Exchange (ETDEWEB)

    Geringer, B. (ed.) [Technische Univ., Vienna (Austria); Loch, A.

    2007-07-01

    The main aim of research and development in the field of internal combustion engine is to create an engine with low fuel consumption and hence low carbon dioxide emissions to meet future emissions regulations as well as providing a good driving experience. Homogeneous charge compression ignition (HCCI) is an alternative combustion process being currently developed that promises a good fuel consumption rate and low nitrogen oxide emissions for the gasoline engine. The only legally restricted exhaust gas emissions for this combustion process are carbon monoxide (CO) and hydrocarbons (HC). The aim of this research was a better understanding of the causes and sources of hydrocarbon emissions with HCCI using gasoline so as to further reduce hydrocarbon emissions. A description of the HCCI combustion process is followed by a list of the known sources of hydrocarbon emission in conventional gasoline engines and current knowledge of the causes of hydrocarbon emission with HCCI. It is assumed that many of the known causes of hydrocarbon emissions in the conventional gasoline combustion process are the same for HCCI. For this reason, this study focused on combustion and carburation, which is where the combustion processes differ the most. (orig.)

  15. Developing Mathematical Provisions for Assessment of Liquid Hydrocarbon Emissions in Emergency Situations

    Science.gov (United States)

    Zemenkova, M. Yu; Zemenkov, Yu D.; Shantarin, V. D.

    2016-10-01

    The paper reviews the development of methodology for calculation of hydrocarbon emissions during seepage and evaporation to monitor the reliability and safety of hydrocarbon storage and transportation. The authors have analyzed existing methods, models and techniques for assessing the amount of evaporated oil. Models used for predicting the material balance of multicomponent two-phase systems have been discussed. The results of modeling the open-air hydrocarbon evaporation from an oil spill are provided and exemplified by an emergency pit. Dependences and systems of differential equations have been obtained to assess parameters of mass transfer from the open surface of a liquid multicomponent mixture.

  16. 33 CFR 157.132 - Cargo tanks: Hydrocarbon vapor emissions.

    Science.gov (United States)

    2010-07-01

    ...(a)(2) or § 157.10c(b)(2) without sufficient segregated ballast tanks or dedicated clean ballast... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Cargo tanks: Hydrocarbon vapor... SECURITY (CONTINUED) POLLUTION RULES FOR THE PROTECTION OF THE MARINE ENVIRONMENT RELATING TO TANK...

  17. THE RATES OF POLYCYCLIC AROMATIC HYDROCARBON EMISSIONS FROM INCENSE BURNING

    Science.gov (United States)

    The paper presents the results of experiments performed to determine the amounts of gas- and particle-phase polycyclic aromatic hydrocarbons (PAHS) in incense smoke. Ten brands of incense, 3 of stick, 2 of joss stick, and one each of cone, smudge bundle, rope, powder, and rock, w...

  18. First detection of HC515N in the interstellar medium

    Science.gov (United States)

    Taniguchi, Kotomi; Saito, Masao

    2017-10-01

    We report the first detection of HC515N with the J = 9-8 rotational line from the cyanopolyyne peak in Taurus Molecular Cloud-1 (TMC-1 CP) using the 45 m radio telescope of the Nobeyama Radio Observatory. The column density of HC515N is derived to be (1.9 ± 0.5) × 1011 cm-2 (1σ). We apply the double-isotope method to derive the 14N/15N ratios of HC5N and HC3N in TMC-1 CP. The 14N/15N ratios are calculated to be 344 ± 53 and 257 ± 54 for HC5N and HC3N, respectively. The 14N/15N ratio of HC5N is lower than the elemental ratio in the local interstellar medium (˜440) and slightly higher than that of HC3N in TMC-1 CP. Since HC3N is formed via the neutral-neutral reaction between C2H2 and CN, the slightly higher 14N/15N ratio of HC5N may support our previous suggestions that the main formation mechanism of HC5N is the ion-molecule reactions between hydrocarbon ions (C5Hn+) and nitrogen atoms.

  19. 醇醚双燃料压燃发动机 HC排放研究%Research on HC Emission of Compression Ignition Engine Fueled with Methanol/DME Dual Fuel

    Institute of Scientific and Technical Information of China (English)

    闫妍; 张煜盛; 佘金平; 陈涌填; 谌祖迪

    2013-01-01

    以ZS195型直喷式柴油机为原型机,开展了进气道喷射醇醚混合燃料HCCI试验研究,并应用气相色谱和傅里叶红外技术对 HC排放物进行检测,详细分析了 HC排放的主要组成和变化规律。试验研究结果表明:双燃料HCCI试验的指示热效率受负荷和燃料比例影响明显,最高可达到49%,超过原柴油机10%;HC排放明显高于原柴油机,通过精密控制双燃料喷射比例和进气加温措施,能够有效降低 HC排放;二甲醚、甲醇和甲醛是 HC排放最主要的组成部分,其中甲醇在大负荷工况下排放比例会有所增大,甲醛排放受功率的影响较小,在接近爆震边界的时候会出现明显提升。%For ZS195 direct injection diesel engine ,the HCCI experiments of intake methanol/DME injection were carried out , the HC emission was measured with the gas chromatography and Fourier transform infrared technology ,and the main compo-nents and their change of HC pollutants were analyzed in detail .The results show that the indicated thermal efficiency of dual fuel is influenced by the load and mixing ratio .The highest indicated thermal efficiency is 10% higher than that of original en-gine and can reach 49% .HCCI method produces higher HC emission ,but precise control of dual fuel ratio and intake warming can reduce the HC emission effectively .DME (dimethyl ether) ,methanol and formaldehyde are the main composition of HC e-mission .The methanol proportion will increase in high load conditions and the formaldehyde emission which is slightly affected by the power will increase significantly near the knock boundary .

  20. Hydrocarbon emissions from gas engine CHP-units. 2011 measurement program

    Energy Technology Data Exchange (ETDEWEB)

    Van Dijk, G.H.J. [KEMA, Arnhem (Netherlands)

    2012-06-15

    In December 2009, the Ministry of Infrastructure and Environment (IandM) issued the Decree on Emission Limits for Middle Sized Combustion Installations (BEMS). This decree imposes a first-time emission limit value (ELV) of 1500 mg C/m{sup 3}{sub o} at 3% O{sub 2} for hydrocarbons emitted by gas engines. IandM used the findings of two hydrocarbon emission measurement programs, executed in 2007 and 2009, as a guideline for this initial ELV. The programs did reveal substantial variation in the hydrocarbon emissions of the gas engines tested. This variation, and especially the uncertainty as to the role of engine and/or other parameters causing such variation, was felt to hamper further policy development. IandM therefore commissioned KEMA to perform follow-up measurements on ten gas engine CHP-units in 2011. Aim of this 2011 program is to assess hydrocarbon emission variation in relation to engine parameters and process conditions including maintenance status, and to atmospheric conditions. The 2011 program comprised two identical measurement sessions, one in spring and one in winter.

  1. Hydrocarbons Emissions Due to Wellbore and other Subsurface Leakage in the Uintah Basin, Utah

    Science.gov (United States)

    Watkins, C.; Lyman, S. N.

    2015-12-01

    The explosive growth of oil and gas production in the United States has focused public and regulatory attention on environmental impacts of hydrocarbon extraction, including air quality and climate impacts. One potentially important emissions source is subsurface leakage of natural gas. Better understanding of wellbore and other subsurface leaks are important in providing ways to decrease pollution while increasing the efficiency of oil and gas production. Soil gas measurements carried out by USGS over the last several years in Utah's oil and gas fields have shown that, while concentrations of methane in soils near wells are typically low, soil gas near some wells can contain more than 50% methane. In the summers of 2013-2015 we carried out campaigns to measure the emission rate of methane and other hydrocarbons from soils near wells in the Uintah Basin, Utah. We also measured emissions at several locations on individual well pads and determined that concentrations of hydrocarbons tend to decrease with distance from the well head. Soil emissions were also measured at non-well sites in the same area to determine background emission rates. Emissions from exposed coal, oil shale, gilsonite, and fault zone surfaces were also measured. Relationships of emissions with soil gas concentrations, meteorological conditions, and soil properties were also investigated.

  2. Estimated IR and phosphorescence emission fluxes for specific Polycyclic Aromatic Hydrocarbons in the Red Rectangle

    CERN Document Server

    Mulas, G; Joblin, C; Toublanc, D

    2005-01-01

    Following the tentative identification of the blue luminescence in the Red Rectangle by Vijh et al. (2005), we compute absolute fluxes for the vibrational IR emission and phosphorescence bands of three small polycyclic aromatic hydrocarbons. The calculated IR spectra are compared with available ISO observations. A subset of the emission bands are predicted to be observable using presently available facilities, and can be used for an immediate, independent, discriminating test on their alleged presence in this well-known astronomical object.

  3. Emissions of Parent, Nitro, and Oxygenated Polycyclic Aromatic Hydrocarbons from Residential Wood Combustion in Rural China

    OpenAIRE

    SHEN, Guofeng; TAO, SHU; WEI, Siye; ZHANG, Yanyan; Wang, Rong; Wang, Bin; Li, Wei; Shen, Huizhong; HUANG, YE; Chen, Yuanchen; Chen, Han; Yang, Yifeng; Wang, Wei; Wang, Xilong; Liu, Wenxin

    2012-01-01

    Residential wood combustion is one of the important sources of air pollution in developing countries. Among the pollutants emitted, parent polycyclic aromatic hydrocarbons (pPAHs) and their derivatives, including nitrated and oxygenated PAHs (nPAHs and oPAHs), are of concern because of their mutagenic and carcinogenic effects. In order to evaluate their impacts on regional air quality and human health, emission inventories, based on realistic emission factors (EFs), are needed. In this study,...

  4. Hydrogen sulfide and nonmethane hydrocarbon emissions from broiler houses in the Southeastern United States

    Science.gov (United States)

    Hydrogen sulfide (H2S) and nonmethane hydrocarbon (NMHC) emissions from two mechanically ventilated commercial broiler houses located in the Southeastern United States were continuously monitored over 12 flocks during the one-year period of 2006-2007 as a joint effort between Iowa State University a...

  5. Nitrous oxide emissions in a membrane bioreactor treating saline wastewater contaminated by hydrocarbons.

    Science.gov (United States)

    Mannina, Giorgio; Cosenza, Alida; Di Trapani, Daniele; Laudicina, Vito Armando; Morici, Claudia; Ødegaard, Hallvard

    2016-11-01

    The joint effect of wastewater salinity and hydrocarbons on nitrous oxide emission was investigated. The membrane bioreactor pilot plant was operated with two phases: i. biomass acclimation by increasing salinity from 10gNaClL(-1) to 20gNaClL(-1) (Phase I); ii. hydrocarbons dosing at 20mgL(-1) with a constant salt concentration of 20gNaClL(-1) (Phase II). The Phase I revealed a relationship between nitrous oxide emissions and salinity. During the end of the Phase I, the activity of nitrifiers started to recover, indicating a partial acclimatization. During the Phase II, the hydrocarbon shock induced a temporary inhibition of the biomass with the suppression of nitrous oxide emissions. The results revealed that the oxic tank was the major source of nitrous oxide emission, likely due to the gas stripping by aeration. The joint effect of salinity and hydrocarbons was found to be crucial for the production of nitrous oxide.

  6. THE GEOLOGICAL CONDITIONING OF HYDROCARBON EMISSIONS RESULTING FROM SOIL CONTAMINATION

    Directory of Open Access Journals (Sweden)

    Ewa J. Lipińska

    2014-12-01

    Full Text Available Synchronization economy of oil mining and mineral waters is associated with planning the functions of spa treatment. Environmental protection of the spa areas also applies to preserve their technical and cultural heritage. This article attempts to determine the places of natural and anthropogenic hydrocarbon pollution substances. Their presence in the soil affects the quality of the environment. As a result, maps are produced showing directions of research: (1 the natural background of biodiversity, and (2 potential anthropogenic pollution. They are assessed in the context of the health and human life, protection of the environment and the possibility of damage to the environment. Research is conducted in communes of the status of the spa – for special protection.

  7. Investigation on Methane Decomposition and the Formation of C2 Hydrocarbons in DC Discharge Plasma byEmission Spectroscopy

    Institute of Scientific and Technical Information of China (English)

    贺建勋; 韩媛媛; 高爱华; 周引穗; 陆治国

    2004-01-01

    The IR emission spectra of methane were measured under DC glow discharge conditions. The distinct difference in time between methane decomposition and C2 hydrocarbons formation was specially pointed out. C2 hydrocarbons formed at the end of methane decomposition. The optimum condition for C2 hydrocarbon formation was studied and the optimum combination between electric current density and methane input quantity was suggested. The appropriate reaction conditions for methane decomposition and C2 hydrocarbons formation are different, so high yield of C2 hydrocarbons will be probably obtained when different conditions are taken.

  8. Geochemical Prospecting Method and Results of Direct Acquisition of Free Gaseous HC

    Institute of Scientific and Technical Information of China (English)

    SongXilin; WangShixin; SuoXiaodong

    2003-01-01

    Geochemistry has been utilized in the petroleum exploration for tens of years. The hydrocarbon halo in the near surface above the oil and gas pool has three kinds of state, i.e., free gaseous HC, absorbed HC and dissolved HC.The optimum choice in the geochemical prospecting is directly testing the free HC. The gas chromatography for free HC was imported and improved in the Division in the early 1990s, realizing the acquiring, analyzing, processing and interpreting free HC samples in the field and in real time. Marked geological result and economical effect were achieved during the many years'' practices.

  9. ANALYSIS OF HYDROCARBON TREATING SYSTEM TO THE EMISSION OFF SPARK-IGNITION FOUR-STROKE ENGINE

    Directory of Open Access Journals (Sweden)

    Binyamin Binyamin

    2016-08-01

    Full Text Available The reduction of carbon monoxide (CO, unburnthydrocarbon (UHC emission and fuel consumption on spark-ignition four-stroke engine is continuously attempted. The purposes from this research were to determine the effect of Hydrocarbon Treating System (HTS  on levels of CO, UHC and fuel consumption. This is an experimental research. Its is conducted by comparing the exhaust pollutant concentration such as carbon monoxide, unburnt hydrocarbon and also fuel consumption between standard engine setting and Hydrocarbon Treating System applied. The research variable are HTS flow rate from Q1 = 0 cc/s (without HTS, Q2 = 1,5 cc/s, Q3 = 2 cc/s, Q4 = 2,5 cc/s, and Q5 = 33 cc/s. The research will be done in three conditions which are low, medium and high rotation. The result showed that Hydrocarbon Threating System decrease fuel consumption up to 19,43% with flow rate Q5 = 3 cc/s, but on the other hand it increase CO emission up to 80.84% with flow rate Q5 = 3 cc/s and UHC emission level up to 124.75% with flow rate Q5 = 3 cc/s from engine standart condition.

  10. Improving Dryer and Press Efficiencies Through Combustion of Hydrocarbon Emissions

    Energy Technology Data Exchange (ETDEWEB)

    Sujit Banerjee

    2005-10-31

    Emission control devices on dryers and presses have been legislated into the industry, and are now an integral part of the drying system. These devices consume large quantities of natural gas and electricity and down-sizing or eliminating them will provide major energy savings. The principal strategy taken here focuses on developing process changes that should minimize (and in some cases eliminate) the need for controls. A second approach is to develop lower-cost control options. It has been shown in laboratory and full-scale work that Hazardous Air Pollutants (HAPs) emerge mainly at the end of the press cycle for particleboard, and, by extension, to other prod-ucts. Hence, only the air associated with this point of the cycle need be captured and treated. A model for estimating terpene emissions in the various zones of veneer dryers has been developed. This should allow the emissions to be concentrated in some zones and minimized in others, so that some of the air could be directly released without controls. Low-cost catalysts have been developed for controlling HAPs from dryers and presses. Catalysts conventionally used for regenerative catalytic oxidizers can be used at much lower temperatures for treating press emissions. Fluidized wood ash is an especially inexpensive mate-rial for efficiently reducing formaldehyde in dryer emissions. A heat transfer model for estimating pinene emissions from hot-pressing strand for the manufacture of flakeboard has been constructed from first principles and validated. The model shows that most of the emissions originate from the 1-mm layer of wood adjoining the platen surface. Hence, a simple control option is to surface a softwood mat with a layer of hardwood prior to pressing. Fines release a disproportionate large quantity of HAPs, and it has been shown both theo-retically and in full-scale work that particles smaller than 400 µm are principally responsible. Georgia-Pacific is considering green

  11. Emission factors of carbonaceous particulate matter and polycyclic aromatic hydrocarbons from residential solid fuel combustions

    Energy Technology Data Exchange (ETDEWEB)

    Shen, Guofeng [Jiangsu Academy of Environmental Science, Nanjing (China). Inst. of Atmospheric Sciences

    2014-07-01

    Emission inventory is basic for the understanding of environmental behaviors and potential effects of compounds, however, current inventories are often associated with relatively high uncertainties. One important reason is the lack of emission factors, especially for the residential solid fuel combustion in developing countries. In the present study, emission factors of a group of pollutants including particulate matter, organic carbon, elemental carbon (sometimes known as black carbon) and polycyclic aromatic hydrocarbons were measured for a variety of residential solid fuels including coal, crop straw, wood, and biomass pellets in rural China. The study provided a large number of emission factors that can be further used in emission estimation. Composition profiles and isomer ratios were investigated and compared so as to be used in source apportionment. In addition, the present study identified and quantified the influence of factors like fuel moisture, volatile matter on emission performance.

  12. Modelo hipermedia creador (HC

    Directory of Open Access Journals (Sweden)

    Manuel Armenteros Gallardo

    2012-04-01

    Full Text Available El presente artículo expone las bases creativas del modelo Hipermedia Creador (HC, un modelo basado en la filosofía de los llamados tutores inteligentes. Tiene como objetivo la creación de una herramienta hipermedia que permita y facilite la producción creativa de proyectos hipermedias educativos con parámetros comunes a los usados en la fórmula del videojuego (entretenimiento. Se describe su estructura, y se analiza y explica la disposición creativa de sus elementos, entre los cuales sobresale las posibilidades pedagógicas del movimiento expresivo de la imagen.

  13. Prediction of cold start hydrocarbon emissions of air cooled two wheeler spark ignition engines by simple fuzzy logic simulation

    Directory of Open Access Journals (Sweden)

    Samuel Raja Ayyanan

    2014-01-01

    Full Text Available The cold start hydrocarbon emission from the increasing population of two wheelers in countries like India is one of the research issues to be addressed. This work describes the prediction of cold start hydrocarbon emissions from air cooled spark ignition engines through fuzzy logic technique. Hydrocarbon emissions were experimentally measured from test engines of different cubic capacity, at different lubricating oil temperature and at different idling speeds with and without secondary air supply in exhaust. The experimental data were used as input for modeling average hydrocarbon emissions for 180 seconds counted from cold start and warm start of gasoline bike engines. In fuzzy logic simulation, member functions were assigned for input variables (cubic capacity and idling rpm and output variables (average hydrocarbon emission for first 180 seconds at cold start and warm start. The knowledge based rules were adopted from the analyzed experimental data and separate simulations were carried out for predicting hydrocarbon emissions from engines equipped with and without secondary air supply. The simulation yielded the average hydrocarbon emissions of air cooled gasoline engine for a set of given input data with accuracy over 90%.

  14. Estimates for biogenic non-methane hydrocarbons and nitric oxide emissions in the Valley of Mexico

    Science.gov (United States)

    Velasco, Erik

    Biogenic non-methane hydrocarbons (NMHC), 2-methyl-3-buten-2-ol (methylbutenol or MBO) and nitrogen oxide (NO) emissions were estimated for the Valley of Mexico developing a spatially and temporally resolved emission inventory for air quality models. The modeling domain includes all the Metropolitan Mexico City Area, the surrounding forests and agriculture fields. The estimates were based on several sources of land use and land cover data and a biogenic emission model; the biomass density and tree characteristics were obtained from reforestation program data. The biogenic emissions depend also on climatic conditions, mainly temperature and solar radiation. The temperature was obtained from a statistical revision of the last 10 yr data reported by the Mexico City Automatic Atmospheric Monitoring Network, while the solar radiation data were obtained from measurements performed in a typical oak forest in the Valley and from sources of total solar radiation data for Mexico City. The results indicated that 7% of total hydrocarbon emissions in Mexico Valley are due to vegetation and NO emissions from soil contribute with 1% to the total NO x emissions.

  15. Measurements of hydrocarbons, oxygenated hydrocarbons, carbon monoxide, and nitrogen oxides in an urban basin in Colorado: Implications for Emission Inventories

    Science.gov (United States)

    Goldan, P. D.; Trainer, M.; Kuster, W. C.; Parrish, D. D.; Carpenter, J.; Roberts, J. M.; Yee, J. E.; Fehsenfeld, F. C.

    1995-11-01

    Concentrations of a wide variety of volatile organic compounds (VOCs) in the C3 to C10 range, CO, NOy (total reactive oxidized nitrogen), SO2, and meteorological parameters were measured concurrently at a site on the western perimeter of Boulder, Colorado, during February 1991. The measurement site, located some 150 m above the Boulder urban basin, receives air masses typifying averaged local sources. The highest hydrocarbon concentrations observed showed little effects of photochemical loss processes and reflect the pattern of the local emission sources. The observed ratios of CO and the VOCs to NOy are compared to those predicted by the 1985 National Acid Precipitation Assessment Program (NAPAP) inventory.These comparisons indicate (1) good agreement for CO/NOY, (2) significant overpredictions by the NAPAP inventory for many of the hydrocarbon to NOY ratios, (3) much more benzene from mobile sources (and less from area sources) than predicted by the NAPAP inventory, and (4) large underpredictions of the light alcohols and carbonyls by the NAPAP inventory. These first two results are in marked contrast to the conclusions of the recent tunnel study reported by Ingalls in 1989. Source profile reconciliation implies substantial input from both a local propane source and gasoline headspace venting.

  16. Method of treating emissions of a hybrid vehicle with a hydrocarbon absorber and a catalyst bypass system

    Science.gov (United States)

    Roos, Bryan Nathaniel; Gonze, Eugene V; Santoso, Halim G; Spohn, Brian L

    2014-01-14

    A method of treating emissions from an internal combustion engine of a hybrid vehicle includes directing a flow of air created by the internal combustion engine when the internal combustion engine is spinning but not being fueled through a hydrocarbon absorber to collect hydrocarbons within the flow of air. When the hydrocarbon absorber is full and unable to collect additional hydrocarbons, the flow of air is directed through an electrically heated catalyst to treat the flow of air and remove the hydrocarbons. When the hydrocarbon absorber is not full and able to collect additional hydrocarbons, the flow of air is directed through a bypass path that bypasses the electrically heated catalyst to conserve the thermal energy stored within the electrically heated catalyst.

  17. Compilation of a source profile database for hydrocarbon and OVOC emissions in China

    Science.gov (United States)

    Mo, Ziwei; Shao, Min; Lu, Sihua

    2016-10-01

    Source profiles are essential for quantifying the role of volatile organic compound (VOC) emissions in air pollution. This study compiled a database of VOC source profiles in China, with 75 species drawn from five major categories: transportation, solvent use, biomass burning, fossil fuel burning, and industrial processes. Source profiles were updated for diesel vehicles, biomass burning, and residential coal burning by measuring both hydrocarbons and oxygenated VOCs (OVOCs), while other source profiles were derived from the available literature. The OVOCs contributed 53.8% of total VOCs in the profiles of heavy - duty diesel vehicle exhaust and 12.4%-46.3% in biomass and residential coal burning, which indicated the importance of primary OVOCs emissions from combustion-related sources. Taking the national emission inventory from 2008 as an example, we established an approach for assigning source profiles to develop a speciation-specific VOC and OVOC emission inventory. The results showed that aromatics contributed 30% of the total 26 Tg VOCs, followed by alkanes (24%), alkenes (19%) and OVOCs (12%). Aromatics (7.9 Tg) were much higher than in previous results (1.1 Tg and 3.4 Tg), while OVOCs (3.1 Tg) were comparable with the 3.3 Tg and 4.3 Tg reported in studies using profiles from the US. The current emission inventories were built based on emission factors from non-methane hydrocarbon measurements, and therefore the proportions from OVOC emissions was neglected, leading to up to 30% underestimation of total VOC emissions. As a result, there is a need to deploy appropriate emission factors and source profiles that include OVOC measurements to reduce the uncertainty of estimated emissions and chemical reactivity potential.

  18. The relationship between polycyclic aromatic hydrocarbon emission and far-infrared dust emission from NGC 2403 and M83

    CERN Document Server

    Jones, A G; Baes, M; Boquien, M; Boselli, A; De Looze, I; Fritz, J; Galliano, F; Hughes, T M; Lebouteiller, V; Lu, N; Madden, S C; Remy-Ruyer, A; Smith, M W L; Spinoglio, L; Zijlstra, A A

    2014-01-01

    We examine the relation between polycyclic aromatic hydrocarbon (PAH) emission at 8 microns and far-infrared emission from hot dust grains at 24 microns and from large dust grains at 160 and 250 microns in the nearby spiral galaxies NGC 2403 and M83 using data from the Spitzer Space Telescope and Herschel Space Observatory. We find that the PAH emission in NGC 2403 is better correlated with emission at 250 microns from dust heated by the diffuse interstellar radiation field (ISRF) and that the 8/250 micron surface brightness ratio is well-correlated with the stellar surface brightness as measured at 3.6 microns. This implies that the PAHs in NGC 2403 are intermixed with cold large dust grains in the diffuse interstellar medium (ISM) and that the PAHs are excited by the diffuse ISRF. In M83, the PAH emission appears more strongly correlated with 160 micron emission originating from large dust grains heated by star forming regions. However, the PAH emission in M83 is low where the 24 micron emission peaks withi...

  19. Characterization of hydrocarbon emissions from green sand foundry core binders by analytical pyrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Yujue Wang; Fred S. Cannon; Magda Salama; Jeff Goudzwaard; James C. Furness [Pennsylvania State University, University Park, PA (United States). Department of Civil and Environmental Engineering

    2007-11-15

    Analytical pyrolysis was conducted to compare the hydrocarbon and greenhouse gas emissions of three foundry sand binders: (a) conventional phenolic urethane resin, (b) biodiesel phenolic urethane resin, and (c) collagen-based binder. These binders are used in the metal casting industry to create internal cavities within castings. Green sand contains silica sand, clay, carbonaceous additives (eg bituminous coal) and water. The core samples were flash pyrolyzed in a Curie-point pyrolyzer at 920{sup o}C with a heating rate of about 3000{sup o}C/sec. This simulated some key features of the fast heating conditions that the core binders would experience at the metal-core interface when molten metal is poured into green sand molds. The core samples were also pyrolyzed in a thermogravimetric analyzer (TGA) from ambient temperature to 1000{sup o}C with a heating rate of 30{sup o}C/min, and this simulated key features of the slow heating conditions that the core binders would experience at distances that are further away from the metal-core interface during casting cooling. Hydrocarbon emissions from flash pyrolysis were analyzed with a gas chromatography-flame ionization detector, while hydrocarbon and greenhouse gas emissions from TGA pyrolysis were monitored with mass spectrometry. The prominent hazardous air pollutant emissions during pyrolysis of the three binders were phenol, cresols, benzene, and toluene for the conventional phenolic urethane resin and biodiesel resin, and benzene and toluene for the collagen-based binder. Bench-scale analytical pyrolysis techniques could be a useful screening tool for the foundries to compare the relative emissions of alternative core binders and to choose proper materials in order to comply with air-emission regulations. 20 refs., 4 figs., 1 tab.

  20. Novel techniques for characterization of hydrocarbon emission sources in the Barnett Shale

    Science.gov (United States)

    Nathan, Brian Joseph

    Changes in ambient atmospheric hydrocarbon concentrations can have both short-term and long-term effects on the atmosphere and on human health. Thus, accurate characterization of emissions sources is critically important. The recent boom in shale gas production has led to an increase in hydrocarbon emissions from associated processes, though the exact extent is uncertain. As an original quantification technique, a model airplane equipped with a specially-designed, open-path methane sensor was flown multiple times over a natural gas compressor station in the Barnett Shale in October 2013. A linear optimization was introduced to a standard Gaussian plume model in an effort to determine the most probable emission rate coming from the station. This is shown to be a suitable approach given an ideal source with a single, central plume. Separately, an analysis was performed to characterize the nonmethane hydrocarbons in the Barnett during the same period. Starting with ambient hourly concentration measurements of forty-six hydrocarbon species, Lagrangian air parcel trajectories were implemented in a meteorological model to extend the resolution of these measurements and achieve domain-fillings of the region for the period of interest. A self-organizing map (a type of unsupervised classification) was then utilized to reduce the dimensionality of the total multivariate set of grids into characteristic one-dimensional signatures. By also introducing a self-organizing map classification of the contemporary wind measurements, the spatial hydrocarbon characterizations are analyzed for periods with similar wind conditions. The accuracy of the classification is verified through assessment of observed spatial mixing ratio enhancements of key species, through site-comparisons with a related long-term study, and through a random forest analysis (an ensemble learning method of supervised classification) to determine the most important species for defining key classes. The hydrocarbon

  1. Global atmospheric emission inventory of polycyclic aromatic hydrocarbons (PAHs) for 2004

    Science.gov (United States)

    Zhang, Yanxu; Tao, Shu

    The global atmospheric emissions of the 16 polycyclic aromatic hydrocarbons (PAHs) listed as the US EPA priority pollutants were estimated using reported emission activity and emission factor data for the reference year 2004. A database for emission factors was compiled, and their geometric means and frequency distributions applied for emission calculation and uncertainty analysis, respectively. The results for 37 countries were compared with other PAH emission inventories. It was estimated that the total global atmospheric emission of these 16 PAHs in 2004 was 520 giga grams per year (Gg y -1) with biofuel (56.7%), wildfire (17.0%) and consumer product usage (6.9%) as the major sources, and China (114 Gg y -1), India (90 Gg y -1) and United States (32 Gg y -1) were the top three countries with the highest PAH emissions. The PAH sources in the individual countries varied remarkably. For example, biofuel burning was the dominant PAH source in India, wildfire emissions were the dominant PAH source in Brazil, while consumer products were the major PAH emission source in the United States. In China, in addition to biomass combustion, coke ovens were a significant source of PAHs. Globally, benzo(a)pyrene accounted for 0.05% to 2.08% of the total PAH emission, with developing countries accounting for the higher percentages. The PAH emission density varied dramatically from 0.0013 kg km -2 y in the Falkland Islands to 360 kg km -2 y in Singapore with a global mean value of 3.98 kg km -2 y. The atmospheric emission of PAHs was positively correlated to the country's gross domestic product and negatively correlated with average income. Finally, a linear bivariate regression model was developed to explain the global PAH emission data.

  2. Characteristics of polycyclic aromatic hydrocarbon emissions of particles of various sizes from smoldering incense.

    Science.gov (United States)

    Yang, T T; Lin, T S; Wu, J J; Jhuang, F J

    2012-02-01

    Release of polycyclic aromatic hydrocarbons (PAHs) in particles of various sizes from smoldering incenses was determined. Among the three types of incense investigated, yielding the total PAH emission rate and factor ranges for PM0.25 were 2,139.7-6,595.6 ng/h and 1,762.2-8,094.9 ng/g, respectively. The PM0.25/PM2.5 ratio of total PAH emission factors and rates from smoldering three incenses was greater than 0.92. This study shows that total particle PAH emission rates and factors were mainly incenses. The benzo[a]pyrene accounted for 65.2%-68.0% of the total toxic equivalency emission factor of PM2.5 for the three incenses. Experimental results clearly indicate that the PAH emission rates and factors were influenced significantly by incense composition, including carbon and hydrogen content. The study concludes that smoldering incense with low atomic hydrogen/carbon ratios minimized the production of total polycyclic aromatic hydrocarbons of both PM2.5 and PM0.25.

  3. Sensitivity of ozone predictions to biogenic hydrocarbon chemistry and emissions in air quality models

    Energy Technology Data Exchange (ETDEWEB)

    Jang, C.J.; Lo, S.C.Y.; Vukovich, J.; Kasibhatla, P. [MCNC-North Carolina Supercomputing Center, Research Triangle Park, NC (United States)

    1997-12-31

    Over the last decade, there is growing evidence that biogenic hydrocarbons play an important role in regional and urban ozone (O{sub 3}) formation in the United States. As a result, the regulatory guidelines issued by the USEPA require that biogenic emissions be included in photochemical modeling. Significant changes and improvement have also been made for estimating the emissions and chemical reaction rates of biogenic hydrocarbons in air quality models. In this paper the authors examine the sensitivity of ozone predictions to the changes in biogenic hydrocarbon chemistry and emissions and investigate why ozone is sensitive to these changes. They first use a Lagrangian box model, the OZIPR/EKMA model, to examine the differences of O{sub 3} predicted using two sets of chemical mechanisms, the original CB4 mechanism and the updated CB4 mechanism with new isoprene chemistry under various emission scenarios. The results show that in the selected urban case, the updated CB4 mechanism predicted lower O{sub 3} than the original CB4 mechanism because of the lower isoprene incremental reactivity in the updated CB4 mechanism. However, in the selected rural case, the updated CB4 mechanism predicted higher O{sub 3} than the original CB4, which is in contradiction to a recent OTAG study using the updated CB4 mechanism. The Eulerian grid model simulation using the MCNC`s EDSS/MAQSIP system further lends support to the box model results. The grid model simulations show that the updated CB4 mechanism predicts much lower O{sub 3} than the original CB4 mechanism over the areas where significant amount of NO{sub x} is emitted; on the contrary, over the Southeastern US region with high isoprene emission rates, the updated CB4 mechanism predicts much higher O{sub 3}.

  4. Time trend of polycyclic aromatic hydrocarbon emission factors from motor vehicles

    Science.gov (United States)

    Tao, Shu; Shen, Huizhong; Wang, Rong; Sun, Kang

    2010-05-01

    Motor vehicle is an important emission source of polycyclic aromatic hydrocarbons (PAHs) and this is particularly true in urban areas. Motor vehicle emission factors (EFs) for individual PAH compound reported in the literature varied for 4 to 5 orders of magnitude, leading to high uncertainty in emission estimation. In this study, the major factors affecting EFs were investigated and characterized by regression models. Based on the model developed, a motor vehicle PAH emission inventory at country level was developed. It was found that country and model year are the most important factors affecting EFs for PAHs. The influence of the two factors can be quantified by a single parameter of per capita gross domestic production (purchasing power parity), which was used as the independent variables of the regression models. The models developed using randomly selected 80% of measurements and tested with the remained data accounted for 28 to 48% of the variations in EFs for PAHs measured in 16 countries over 50 years. The regression coefficients of the EF prediction models were molecular weight dependent. Motor vehicle emission of PAHs from individual countries in the world in 1985, 1995, 2005, 2015, and 2025 were calculated and the global emission of total PAHs were 470, 390, and 430 Gg in 1985, 1995, and 2005 and will be 290 and 130 Gg in 2015 and 2025, respectively. The emission is currently passing its peak and will decrease due to significant decrease in China and other developing countries.

  5. Emission of Polycyclic Aromatic Hydrocarbons from the Exhalation Zones of Thermally Active Mine Waste Dumps

    Directory of Open Access Journals (Sweden)

    Patrycja Kuna-Gwoździewicz

    2013-01-01

    Full Text Available The article presents results of research carried out on the occurrence of polycyclic aromatic hydrocarbons (PAH in gases of exhalation zones, created on the surface of a thermally active coal mine waste dump. The oxidation and self-heating of mine waste are accompanied with the intensive emission of flue gases, including PAH group compounds. Taking into consideration the fact the hydrocarbons show strong genotoxic, mutagenic and carcinogenic properties, research was conducted to establish their content in the examined gases. The research object was a gangue dump located in Rybnik. The research was performed in 2012. In total, 24 samples of gas were collected with PUF (polyurethane foam sampling cartridges with a quartz fibre filter and an aspirator. The collected samples were analysed with the use of high performance liquid chromatography (HPLC and a fluorescence detector (FLD to evaluate the amount of PAH present.

  6. Toroidally Asymmetric Distributions of Hydrocarbon (CD) Emission and Chemical Sputtering Sources in DIII-D

    Energy Technology Data Exchange (ETDEWEB)

    Groth, M; Brooks, N H; Fenstermacher, M E; Lasnier, C J; McLean, A G; Watkins, J G

    2006-05-16

    Measurements in DIII-D show that the carbon chemical sputtering sources along the inner divertor and center post are toroidally periodic and highest at the upstream tile edge. Imaging with a tangentially viewing camera and visible spectroscopy were used to monitor the emission from molecular hydrocarbons (CH/CD) at 430.8 nm and deuterium neutrals in attached and partially detached divertors of low-confinement mode plasmas. In contrast to the toroidally periodic CD distribution, emission from deuterium neutrals was observed to be toroidally symmetric along the inner strike zone. The toroidal distribution of the measured tile surface temperature in the inner divertor correlates with that of the CD emission, suggesting larger parallel particle and heat fluxes to the upstream tile edge, either due to toroidal tile gaps or height steps between adjacent tiles.

  7. Emissions of polycyclic aromatic hydrocarbons, polychlorinated dibenzo-p-dioxins, and dibenzofurans from incineration of nanomaterials.

    Science.gov (United States)

    Vejerano, Eric P; Holder, Amara L; Marr, Linsey C

    2013-05-07

    Disposal of some nanomaterial-laden waste through incineration is inevitable, and nanomaterials' influence on combustion byproduct formation under high-temperature, oxidative conditions is not well understood. This work reports the formation of polycyclic aromatic hydrocarbons (PAHs) and polychlorinated-dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) from incineration of paper and plastic waste containing various nanomaterials, including titania, nickel oxide, silver, ceria, iron oxide, quantum dots, and C60-fullerene, in a laboratory-scale furnace. The presence of nanomaterials in the waste stream resulted in higher emissions of some PAH species and lower emissions of others, depending on the type of waste. The major PAH species formed were phenanthrene and anthracene, and emissions were sensitive to the amount of nanomaterials in the waste. Generally, there were no significant differences in emission factors for the larger PAH species when nanomaterials were added to the waste. The total PAH emission factors were on average ~6 times higher for waste spiked with nanomaterials v. their bulk counterparts. Emissions of chlorinated dioxins from poly(vinyl chloride) (PVC) waste were not detected; however, chlorinated furans were formed at elevated concentrations with wastes containing silver and titania nanomaterials, and toxicity was attributable mainly to 2,3,4,7,8-pentachlorodibenzofuran. The combination of high specific surface area and catalytic, including electrocatalytic, properties of nanomaterials might be responsible for affecting the formation of toxic pollutants during incineration.

  8. Air pollution from a large steel factory: polycyclic aromatic hydrocarbon emissions from coke-oven batteries.

    Science.gov (United States)

    Liberti, Lorenzo; Notarnicola, Michele; Primerano, Roberto; Zannetti, Paolo

    2006-03-01

    A systematic investigation of solid and gaseous atmospheric emissions from some coke-oven batteries of one of Europe's largest integrated steel factory (Taranto, Italy) has been carried out. In air monitoring samples, polycyclic aromatic hydrocarbons (PAHs) were consistently detected at concentrations largely exceeding threshold limit values. By means of PAHs speciation profile and benzo(a)pyrene (BaP) equivalent dispersion modeling from diffuse sources, the study indicated that serious health risks exist not only in working areas, but also in a densely populated residential district near the factory.

  9. The emissions of monoaromatic hydrocarbons from small polymeric toys placed in chocolate food products.

    Science.gov (United States)

    Marć, Mariusz; Formela, Krzysztof; Klein, Marek; Namieśnik, Jacek; Zabiegała, Bożena

    2015-10-15

    The article presents findings on the emissions of selected monoaromatic hydrocarbons from children's toys placed in chocolate food products. The emission test system involved the application of a new type of microscale stationary emission chamber, μ-CTE™ 250. In order to determine the type of the applied polymer in the manufacture of the tested toys, Fourier transform infrared spectroscopy and thermogravimetric analysis coupled with differential scanning calorimetry were used. It was found that the tested toy components or the whole toys (figurines) are made of two main types of polymers: polyamide and acrylonitrile-butadiene-styrene copolymer. Total number of studied small polymeric toys was 52. The average emissions of selected monoaromatic hydrocarbons from studied toys made of polyamide were as follows: benzene: 0.45 ± 0.33 ng/g; toluene: 3.3 ± 2.6 ng/g; ethylbenzene: 1.4 ± 1.4 ng/g; p,m-xylene: 2.5 ± 4.5 ng/g; and styrene: 8.2 ± 9.9 ng/g. In the case of studied toys made of acrylonitrile-butadiene-styrene copolymer the average emissions of benzene, toluene, ethylbeznene, p,m-xylene and styrene were: 0.31 ± 0.29 ng/g; 2.5 ± 1.4 ng/g; 4.6 ± 8.9 ng/g; 1.4 ± 1.1 ng/g; and 36 ± 44 ng/g, respectively.

  10. Emission characteristics of polycyclic aromatic hydrocarbons and nitro-polycyclic aromatic hydrocarbons from diesel trucks based on on-road measurements

    Science.gov (United States)

    Cao, Xinyue; Hao, Xuewei; Shen, Xianbao; Jiang, Xi; Wu, Bobo; Yao, Zhiliang

    2017-01-01

    Polycyclic aromatic hydrocarbon (PAH) and nitro-polycyclic aromatic hydrocarbon (NPAH) emissions from 18 diesel trucks of different sizes and with different emission standards were tested in Beijing using a portable emission measurement system (PEMS). Both the gaseous- and particulate-phase PAHs and NPAHs were quantified by high-performance liquid chromatography (HPLC) in the laboratory. The emission factors (EFs) of the total PAHs from light-duty diesel trucks (LDDTs), medium-duty diesel trucks (MDDTs) and heavy-duty diesel trucks (HDDTs) were 82229.11 ± 41906.06, 52867.43 ± 18946.47 and 93837.35 ± 32193.14 μg/km, respectively, much higher than the respective values of total NPAHs from their counterpart vehicles. The gaseous phase had an important contribution to the total PAHs and NPAHs, with a share rate of approximately 69% and 97% on average, respectively. The driving cycle had important impacts on the emissions of PAHs and NPAHs, especially for LDDTs and HDDTs. Higher emissions of PAHs and NPAHs were detected on non-highway roads compared to that on highways for these two types of vehicles. Compared to the results of different studies, the difference in the EFs of PAHs and NPAHs can reach several orders of magnitudes, which would introduce errors in the development of an emission inventory of PAHs and NPAHs.

  11. A Techno-Economic Analysis of Emission Controls on Hydrocarbon Biofuel Production

    Energy Technology Data Exchange (ETDEWEB)

    Bhatt, Arpit; Zhang, Yimin; Davis, Ryan; Eberle, Annika; Heath, Garvin

    2016-06-23

    Biofuels have the potential to reduce our dependency on petroleum-derived transportation fuels and decrease greenhouse gas (GHG) emissions. Although the overall GHG emissions from biofuels are expected to be lower when compared to those of petroleum fuels, the process of converting biomass feedstocks into biofuels emits various air pollutants, which may be subject to federal air quality regulation or emission limits. While prior research has evaluated the technical and economic feasibility of biofuel technologies, gaps still exist in understanding the regulatory issues associated with the biorefineries and their economic implications on biofuel production costs (referred to as minimum fuel selling price (MFSP) in this study). The aim of our research is to evaluate the economic impact of implementing emission reduction technologies at biorefineries and estimate the cost effectiveness of two primary control technologies that may be required for air permitting purposes. We analyze a lignocellulosic sugars-to-hydrocarbon biofuel production pathway developed by the National Renewable Energy Laboratory (NREL) and implement air emission controls in Aspen Plus to evaluate how they affect the MFSP. Results from this analysis can help inform decisions about biorefinery siting and sizing, as well as mitigate the risks associated with air permitting.

  12. Polycyclic aromatic hydrocarbon and mid-infrared continuum emission in a z > 4 submillimeter galaxy

    Energy Technology Data Exchange (ETDEWEB)

    Riechers, Dominik A. [Department of Astronomy, Cornell University, 220 Space Sciences Building, Ithaca, NY 14853 (United States); Pope, Alexandra [Department of Astronomy, University of Massachusetts, Amherst, MA 01003 (United States); Daddi, Emanuele; Elbaz, David [Laboratoire AIM, CEA/DSM-CNRS-Université Paris Diderot, Irfu/Service d' Astrophysique, CEA Saclay, Orme des Merisiers, F-91191 Gif-sur-Yvette Cedex (France); Armus, Lee; Chary, Ranga-Ram [Spitzer Science Center, California Institute of Technology, MC 220-6, 1200 East California Boulevard, Pasadena, CA 91125 (United States); Carilli, Christopher L. [National Radio Astronomy Observatory, PO Box O, Socorro, NM 87801 (United States); Walter, Fabian; Hodge, Jacqueline [Max-Planck-Institut für Astronomie, Königstuhl 17, D-69117 Heidelberg (Germany); Morrison, Glenn E. [Canada-France-Hawaii Telescope, 65-1238 Mamalahoa Hwy, Kamuela, HI 96743-8432 (United States); Dickinson, Mark [National Optical Astronomy Observatory, 950 North Cherry Avenue, Tucson, AZ 85719 (United States); Dannerbauer, Helmut, E-mail: dr@astro.cornell.edu [Institut für Astrophysik, Universität Wien, Türkenschanzstraße 17, A-1180 Wien (Austria)

    2014-05-01

    We report the detection of 6.2 μm polycyclic aromatic hydrocarbon (PAH) and rest-frame 4-7 μm continuum emission in the z = 4.055 submillimeter galaxy GN20, using the Infrared Spectrograph on board the Spitzer Space Telescope. This represents the first detection of PAH emission at z > 4. The strength of the PAH emission feature is consistent with a very high star formation rate of ∼1600 M {sub ☉} yr{sup –1}. We find that this intense starburst powers at least ∼1/3 of the faint underlying 6 μm continuum emission, with an additional, significant (and perhaps dominant) contribution due to a power-law-like hot dust source, which we interpret to likely be a faint, dust-obscured active galactic nucleus (AGN). The inferred 6 μm AGN continuum luminosity is consistent with a sensitive upper limit on the hard X-ray emission as measured by the Chandra X-Ray Observatory if the previously undetected AGN is Compton-thick. This is in agreement with the finding at optical/infrared wavelengths that the galaxy and its nucleus are heavily dust-obscured. Despite the strong power-law component enhancing the mid-infrared continuum emission, the intense starburst associated with the photon-dominated regions that give rise to the PAH emission appears to dominate the total energy output in the infrared. GN20 is one of the most luminous starburst galaxies known at any redshift, embedded in a rich protocluster of star-forming galaxies. This investigation provides an improved understanding of the energy sources that power such exceptional systems, which represent the extreme end of massive galaxy formation at early cosmic times.

  13. Global atmospheric emissions and transport of polycyclic aromatic hydrocarbons: Evaluation of modeling and transboundary pollution

    Science.gov (United States)

    Shen, Huizhong; Tao, Shu

    2014-05-01

    Global atmospheric emissions of 16 polycyclic aromatic hydrocarbons (PAHs) from 69 major sources were estimated for a period from 1960 to 2030. Regression models and a technology split method were used to estimated country and time specific emission factors, resulting in a new estimate of PAH emission factor variation among different countries and over time. PAH emissions in 2007 were spatially resolved to 0.1° × 0.1° grids based on a newly developed global high-resolution fuel combustion inventory (PKU-FUEL-2007). MOZART-4 (The Model for Ozone and Related Chemical Tracers, version 4) was applied to simulate the global tropospheric transport of Benzo(a)pyrene, one of the high molecular weight carcinogenic PAHs, at a horizontal resolution of 1.875° (longitude) × 1.8947° (latitude). The reaction with OH radical, gas/particle partitioning, wet deposition, dry deposition, and dynamic soil/ocean-air exchange of PAHs were considered. The simulation was validated by observations at both background and non-background sites, including Alert site in Canadian High Arctic, EMEP sites in Europe, and other 254 urban/rural sites reported from literatures. Key factors effecting long-range transport of BaP were addressed, and transboundary pollution was discussed.

  14. Random mixtures of polycyclic aromatic hydrocarbon spectra match interstellar infrared emission

    CERN Document Server

    Rosenberg, Marissa J F; Boersma, Christiaan

    2014-01-01

    The mid-infrared (IR; 5-15~$\\mu$m) spectrum of a wide variety of astronomical objects exhibits a set of broad emission features at 6.2, 7.7, 8.6, 11.3 and 12.7 $\\mu$m. About 30 years ago it was proposed that these signatures are due to emission from a family of UV heated nanometer-sized carbonaceous molecules known as polycyclic aromatic hydrocarbons (PAHs), causing them to be referred to as aromatic IR bands (AIBs). Today, the acceptance of the PAH model is far from settled, as the identification of a single PAH in space has not yet been successful and physically relevant theoretical models involving ``true'' PAH cross sections do not reproduce the AIBs in detail. In this paper, we use the NASA Ames PAH IR Spectroscopic Database, which contains over 500 quantum-computed spectra, in conjunction with a simple emission model, to show that the spectrum produced by any random mixture of at least 30 PAHs converges to the same 'kernel'-spectrum. This kernel-spectrum captures the essence of the PAH emission spectrum...

  15. Emission factors of polycyclic aromatic hydrocarbons from domestic coal combustion in China.

    Science.gov (United States)

    Geng, Chunmei; Chen, Jianhua; Yang, Xiaoyang; Ren, Lihong; Yin, Baohui; Liu, Xiaoyu; Bai, Zhipeng

    2014-01-01

    Domestic coal stove is widely used in China, especially for countryside during heating period of winter, and polycyclic aromatic hydrocarbons (PAHs) are important in flue gas of the stove. By using dilution tunnel system, samples of both gaseous and particulate phases from domestic coal combustion were collected and 18 PAH species were analyzed by GC-MS. The average emission factors of total 18 PAH species was 171.73 mg/kg, ranging from 140.75 to 229.11 mg/kg for bituminous coals, while was 93.98 mg/kg, ranging from 58.48 to 129.47 mg/kg for anthracite coals. PAHs in gaseous phases occupied 95% of the total of PAHs emission of coal combustion. In particulate phase, 3-ring and 4-ring PAHs were the main components, accounting for 80% of the total particulate PAHs. The total toxicity potency evaluated by benzo[a]pyrene-equivalent carcinogenic power, sum of 7 carcinogenic PAH components and 2,3,7,8-tetrachlorodibenzodioxin had a similar tendency. And as a result, the toxic potential of bituminous coal was higher than that of anthracite coal. Efficient emission control should be conducted to reduce PAH emissions in order to protect ecosystem and human health.

  16. [Emission factors of polycyclic aromatic hydrocarbons (PAHs) in residential coal combustion and its influence factors].

    Science.gov (United States)

    Hai, Ting-Ting; Chen, Ying-Jun; Wang, Yan; Tian, Chong-Guo; Lin, Tian

    2013-07-01

    As the emission source of polycyclic aromatic hydrocarbons (PAHs), domestic coal combustion has attracted increasing attention in China. According to the coal maturity, combustion form and stove type associated with domestic coal combustion, a large-size, full-flow dilution tunnel and fractional sampling system was employed to collect the emissions from five coals with various maturities, which were burned in the form of raw-coal-chunk (RCC)/honeycomb-coal-briquettes (HCB) in different residential stoves, and then the emission factors of PAHs (EF(PAHs)) were achieved. The results indicate that the EF(PAHs) of bituminous coal ranged from 1.1 mg x kg(-1) to 3.9 mg x kg(-1) for RCC and 2.5 mg x kg(-1) to 21. 1 mg x kg(-1) for HCB, and the anthracite EF(PAH8) were 0.2 mg x kg(-1) for RCC and 0.6 mg x kg(-1) for HCB, respectively. Among all the influence factors of emission factors of PAHs from domestic coal combustion, the maturity of coal played a major role, the range of variance reaching 1 to 2 orders of magnitude in coals with different maturity. Followed by the form of combustion (RCC/HCB), the EF(PAHs) of HCB was 2-6 times higher than that of RCC for the same geological maturity of the coal. The type of stove had little influence on EF(PAHs).

  17. Emission and Size Distribution of Particle-bound Polycyclic Aromatic Hydrocarbons from Residential Wood Combustion

    Science.gov (United States)

    Shen, Guofeng; Wei, Siye; Zhang, Yanyan; Wang, Bin; Wang, Rong; Shen, Huizhong; Li, Wei; Huang, Ye; Chen, Yuanchen; Chen, Han; Tao, Shu

    2015-01-01

    Emissions and size distributions of 28 particle-bound polycyclic aromatic hydrocarbons (PAHs) from residential combustion of 19 fuels in a domestic cooking stove in rural China were studied. Measured emission factors of total PAHs were 1.79±1.55, 12.1±9.1, and 5.36±4.46 mg/kg for fuel wood, brushwood, and bamboo, respectively. Approximate 86.7, 65.0, and 79.7% of the PAHs were associated with fine particulate matter with size less than 2.1 µm for these three types of fuels. Statistically significant difference in emission factors and size distributions of particle-bound PAHs between fuel wood and brushwood was observed, with the former had lower emission factors but more PAHs in finer PM. Mass fraction of the fine particles associated PAHs was found to be positively correlated with fuel density and moisture, and negatively correlated with combustion efficiency. Low and high molecular weight PAHs segregated into the coarse and fine PM, respectively. The high accumulation tendency of the PAHs from residential wood combustion in fine particles implies strong adverse health impact. PMID:25678760

  18. Greenhouse gas impacts of declining hydrocarbon resource quality: Depletion, dynamics, and process emissions

    Science.gov (United States)

    Brandt, Adam Robert

    This dissertation explores the environmental and economic impacts of the transition to hydrocarbon substitutes for conventional petroleum (SCPs). First, mathematical models of oil depletion are reviewed, including the Hubbert model, curve-fitting methods, simulation models, and economic models. The benefits and drawbacks of each method are outlined. I discuss the predictive value of the models and our ability to determine if one model type works best. I argue that forecasting oil depletion without also including substitution with SCPs results in unrealistic projections of future energy supply. I next use information theoretic techniques to test the Hubbert model of oil depletion against five other asymmetric and symmetric curve-fitting models using data from 139 oil producing regions. I also test the assumptions that production curves are symmetric and that production is more bell-shaped in larger regions. Results show that if symmetry is enforced, Gaussian production curves perform best, while if asymmetry is allowed, asymmetric exponential models prove most useful. I also find strong evidence for asymmetry: production declines are consistently less steep than inclines. In order to understand the impacts of oil depletion on GHG emissions, I developed the Regional Optimization Model for Emissions from Oil Substitutes (ROMEO). ROMEO is an economic optimization model of investment and production of fuels. Results indicate that incremental emissions (with demand held constant) from SCPs could be 5-20 GtC over the next 50 years. These results are sensitive to the endowment of conventional oil and not sensitive to a carbon tax. If demand can vary, total emissions could decline under a transition because the higher cost of SCPs lessens overall fuel consumption. Lastly, I study the energetic and environmental characteristics of the in situ conversion process, which utilizes electricity to generate liquid hydrocarbons from oil shale. I model the energy inputs and outputs

  19. Trends of non-methane hydrocarbons (NMHC emissions in Beijing during 2002–2013

    Directory of Open Access Journals (Sweden)

    M. Wang

    2014-07-01

    Full Text Available Non-methane hydrocarbons (NMHCs play a critical role in the photochemical production of ozone (O3 and organic aerosols. Obtaining an accurate understanding on NMHC emission trends is essential for predicting air quality changes and evaluating the effectiveness of current control measures. In this study, we evaluated temporal trends in NMHC emissions in Beijing based on ambient measurements during the summer at an urban site in Beijing from 2002 to 2013. In contrast to the results of the most recent inventory (Multi-resolution Emission Inventory for China, MEIC, which reported that total NMHC emissions increased at a rate of ~4% yr−1, mixing ratios of NMHCs measured at this urban site displayed an obvious decrease (~30% during the last decade. A Positive Matrix Factorization (PMF model was applied to the NMHC measurements for source apportionment, and the results showed a decrease in the concentrations contributed by transportation-related sources to total NMHC emissions by 66% during 2004–2012, which was comparable to the relative decline of 65% reported by the MEIC inventory. This finding indicates that the implementation of stricter emissions standards and control measures has been effective for reducing transportation-related NMHC emissions. In addition, the PMF results suggested that there were no significant temporal changes in NMHC concentrations from paint and solvent use during 2004–2012, in contrast with the rapid rate of increase (27.5% yr−1 reported by the MEIC inventory. To re-evaluate the NMHC emissions trends for paint and solvent use, annual variations in NMHC / NOx ratios were compared between ambient measurements and the MEIC inventory. In contrast to the significant rise in NMHC / NOx ratios from the inventory, the measured ratios declined by 14% during 2005–2012. However, the inferred NMHC / NOx ratios based on PMF results exhibited a comparable decline of 11% to measurements. These results indicate that the increase

  20. Characterization and concentrations of polycyclic aromatic hydrocarbons in emissions from different heating systems in Damascus, Syria.

    Science.gov (United States)

    Alkurdi, Farouk; Karabet, François; Dimashki, Marwan

    2014-04-01

    Traffic has long been recognized as the major contributor to polycyclic aromatic hydrocarbon (PAH) emissions to the urban atmosphere. Stationary combustion sources, including residential space heating systems, are also a major contributor to PAH emissions. The aim of this study was to determine the profile and concentration of PAHs in stack flue gas emissions from different kinds of space heaters in order to increase the understanding of the scale of the PAH pollution problem caused by this source. This study set out to first assess the characteristics of PAHs and their corresponding benzo[a]pyrene equivalent emissions from a few types of domestic heaters and central heating systems to the urban atmosphere. The study, enabled for the first time, the characterization of PAHs in stationary combustion sources in the city of Damascus, Syria. Nine different types of heating systems were selected with respect to age, design, and type of fuel burned. The concentrations of 15 individual PAH compounds in the stack flue gas were determined in the extracts of the collected samples using high-performance liquid chromatography system (HPLC) equipped with ultraviolet-visible and fluorescence detectors. In general, older domestic wood stoves caused considerably higher PAH emissions than modern domestic heaters burning diesel oil. The average concentration of ΣPAH (sum of 15 compounds) in emissions from all types of studied heating systems ranged between 43 ± 0.4 and 316 ± 1.4 μg/m(3). Values of total benzo[a]pyrene equivalent ranged between 0.61 and 15.41 μg/m(3).

  1. Polycyclic aromatic hydrocarbon emissions from the combustion of alternative fuels in a gas turbine engine.

    Science.gov (United States)

    Christie, Simon; Raper, David; Lee, David S; Williams, Paul I; Rye, Lucas; Blakey, Simon; Wilson, Chris W; Lobo, Prem; Hagen, Donald; Whitefield, Philip D

    2012-06-01

    We report on the particulate-bound polycyclic aromatic hydrocarbons (PAH) in the exhaust of a test-bed gas turbine engine when powered by Jet A-1 aviation fuel and a number of alternative fuels: Sasol fully synthetic jet fuel (FSJF), Shell gas-to-liquid (GTL) kerosene, and Jet A-1/GTL 50:50 blended kerosene. The concentration of PAH compounds in the exhaust emissions vary greatly between fuels. Combustion of FSJF produces the greatest total concentration of PAH compounds while combustion of GTL produces the least. However, when PAHs in the exhaust sample are measured in terms of the regulatory marker compound benzo[a]pyrene, then all of the alternative fuels emit a lower concentration of PAH in comparison to Jet A-1. Emissions from the combustion of Jet A-1/GTL blended kerosene were found to have a disproportionately low concentration of PAHs and appear to inherit a greater proportion of the GTL emission characteristics than would be expected from volume fraction alone. The data imply the presence of a nonlinear relation between fuel blend composition and the emission of PAH compounds. For each of the fuels, the speciation of PAH compounds present in the exhaust emissions were found to be remarkably similar (R(2) = 0.94-0.62), and the results do provide evidence to support the premise that PAH speciation is to some extent indicative of the emission source. In contrast, no correlation was found between the PAH species present in the fuel with those subsequently emitted in the exhaust. The results strongly suggests that local air quality measured in terms of the particulate-bound PAH burden could be significantly improved by the use of GTL kerosene either blended with or in place of Jet A-1 kerosene.

  2. Avco Lycoming/NASA contract status. [on reduction of emissions from aircraft piston engines

    Science.gov (United States)

    Duke, L. C.

    1976-01-01

    The standards promulgated by the Environmental Protection Agency (EPA) for carbon monoxide (CO), unburned hydrocarbon (HC), and oxides-of-nitrogen (NOx) emissions were the basis in a study of ways to reduce emissions from aircraft piston engines. A variable valve timing system, ultrasonic fuel atomization, and ignition system changes were postulated.

  3. An investigation on polycyclic aromatic hydrocarbon emissions from pulverized coal combustion systems

    Science.gov (United States)

    Pisupati; Wasco; Scaroni

    2000-05-29

    Results from a series of tests conducted to study the emission of polynuclear or polycyclic aromatic hydrocarbons (PAHs) from bench-scale and small industrial, water-tube boiler are discussed. A Middle Kittanning, and Upper Freeport seam coals were used in the study. Samples were extracted from the reactor outlet and from the inlet and outlet sides of the research boiler's (RB) baghouse using EPA promulgated methods.Only acenaphthene and fluoranthene were detected in down-fired combustor (DFC) samples. In addition to these two, naphthalene was detected in the RB samples. Emission factors ranged from 80 to 320 &mgr;g/kg of fuel fired. Although there were minor trends in the emissions' data, given the reproducibility limits for PAH compounds, no significant differences were found in the emissions with respect to the fuel type or form (pulverized coal (PC) vs. coal-water slurry fuel (CWSF), and raw vs. cleaned coal) and firing conditions (high and low excess air). The PAH emissions showed a decrease with increase in the firing rate.A bench-scale drop-tube reactor (DTR) was used to study the effects of temperature and residence time on PAH formation. The results revealed near constant PAH concentrations in the solid-phase samples, while the PAH concentrations in the vapor-phase samples increased as a function of temperature. At a temperature of around 1300 degrees C, the rate of PAH formation was exceeded by the rate of PAH oxidation, and PAH concentrations in the vapor phase began to decrease.

  4. Indoor emission, dispersion and exposure of total particle-bound polycyclic aromatic hydrocarbons during cooking

    Science.gov (United States)

    Gao, Jun; Jian, Yating; Cao, Changsheng; Chen, Lei; Zhang, Xu

    2015-11-01

    Cooking processes highly contribute to indoor polycyclic aromatic hydrocarbon (PAH) pollution. High molecular weight and potentially carcinogenic PAHs are generally found attached to small particles, i.e., particulate phase PAHs (PPAHs). Due to the fact that indoor particle dynamics have been clear, describing the indoor dynamics of cooking-generated PPAHs within a specific time span is possible. This paper attempted to quantify the dynamic emission rate, simultaneous spatial dispersion and individual exposure of PPAHs using a cooking source. Experiments were conducted in a real-scale kitchen chamber to elucidate the time-resolved emission and effect of edible oil temperature and mass. Numerical simulations based on indoor particle dynamics were performed to obtain the spatial dispersion and individual inhalation intake of PPAHs under different emission and ventilation conditions. The present work examined the preheating cooking stage, at which edible oil is heated up to beyond its smoke point. The dynamic emission rate peak point occurred much earlier than the oil heating temperature. The total PPAH emission ranged from 2258 to 6578 ng upon heating 40-85 g of edible oil. The overall intake fraction by an individual within a period of 10 min, including 3 min for heating and 7 min for natural cooling, was generally ∼1/10,000. An important outcome of this work was that the overall intake fraction could be represented by multiplying the range hood escape efficiency by the inhalation-to-ventilation rate ratio, which would be no greater than the same ratio. The methodology and results of this work were extendible for the number-based assessment of PPAHs. This work is expected to help us understand the health risks due to inhalation exposure to cooking-generated PPAHs in the kitchen.

  5. Emission of polycyclic aromatic hydrocarbons (PAHs) from the liquid injection incineration of petrochemical industrial wastewater.

    Science.gov (United States)

    Wang, Lin-Chi; Wang, I-Ching; Chang, Juu-En; Lai, Soon-Onn; Chang-Chien, Guo-Ping

    2007-09-05

    This study investigated the emission of polycyclic aromatic hydrocarbons (PAHs) from stack flue gas and air pollution control device (APCD) effluent of the liquid injection incinerator (LII) disposing the petrochemical industrial wastewater, and PAH removal efficiencies of wet electrostatic precipitator (WESP) and wet scrubber (WSB). The PAH carcinogenic potency were investigated with the benzo(a)pyrene equivalent concentration (BaP(eq)). The remarkably high total-BaP(eq) concentration (220 microgNm(-3)) in the stack flue gas was much higher than those of several published emission sources, and indicated the possible influence on its surrounding environment. The total-PAH emission factors of the WESP, WSB and stack flue gas were 78.9, 95.7 and 30,900 microgL(-1) wastewater, respectively. The removal efficiencies of total-PAHs were 0.254, 0.309 and 0.563% for WESP, WSB and overall, respectively, suggesting that the use of both WESP and WSB shows insignificant PAH removal efficiencies, and 99.4% of total-PAHs was directly emitted to the ambient air through the stack flue gas. This finding suggested that the better incineration efficiencies, and APCD removal efficiencies for disposing the petrochemical industrial wastewater are necessary in future.

  6. Emission of polycyclic aromatic hydrocarbons and lead during Chinese mid-autumn festival.

    Science.gov (United States)

    Kuo, Chung-Yih; Lee, Hong-Shen; Lai, Jeang-Hung

    2006-07-31

    The emission factors of total particulate polycyclic aromatic hydrocarbons (PAHs), Benzo(a)pyrene (BaP), BaP-equivalent doses (BaP(eq)) and Pb for burning three kinds of charcoal were investigated in this study: fast-lighting charcoal, Taiwanese, and Indonesian charcoal (the latter two of which are not fast-lighting). Compared to the burning of Taiwanese and Indonesian charcoal, the burning of fast-lighting charcoal can emit much larger amounts of total PAHs, BaP(eq) and Pb into the atmosphere. The emission factors of total PAHs, BaP and BaP(eq) for broiling meat were noticeably higher than those for broiling vegetables and non-fish seafood. When using Indonesian charcoal to broil meat, the total emission factors of particulate PAHs and BaP were about 15.7 and 0.39 mg/kg, respectively. The total amounts of particulate PAHs and Pb emitted from cookouts during Mid-Autumn Festival were 2881 and 120 g, respectively. Total PAHs and BaP(eq) in PM(10) aerosols on Mid-Autumn Festival nights increased about 1.6 and 1.5 times, respectively, higher than those on non-festival nights. The mean concentration of Pb on the nights of Mid-Autumn Festival increases to about 2.8 times that of non-festival nights.

  7. The Luminous Polycyclic Aromatic Hydrocarbon Emission Features: Applications to High Redshift Galaxies and Active Galactic Nuclei

    Science.gov (United States)

    Shipley, Heath V.

    2016-01-01

    For decades, significant work has been applied to calibrating emission from the ultra-violet, nebular emission lines, far-infrared, X-ray and radio as tracers of the star-formation rate (SFR) in distant galaxies. Understanding the exact rate of star-formation and how it evolves with time and galaxy mass has deep implications for how galaxies form. The co-evolution of star-formation and supermassive black hole (SMBH) accretion is one of the key problems in galaxy formation theory. But, many of these SFR indicators are influenced by SMBH accretion in galaxies and result in unreliable SFRs. Utilizing the luminous polycyclic aromatic hydrocarbon (PAH) emission features, I provide a new robust SFR calibration using the luminosity emitted from the PAHs at 6.2μm, 7.7μm and 11.3μm to solve this. The PAH features emit strongly in the mid-infrared (mid-IR; 5-25μm) mitigating dust extinction, containing on average 5-10% of the total IR luminosity in galaxies. I use a sample of 105 star-forming galaxies covering a range of total IR luminosity, LIR = L(8-1000μm) = 109 - 1012 L⊙ and redshift 0 blackhole accretion contemporaneously in a galaxy.

  8. Biomass consumption and CO2, CO and main hydrocarbon gas emissions in an Amazonian forest clearing fire

    Science.gov (United States)

    T. G. Soares Neto; J. A. Carvalho; C. A. G. Veras; E. C. Alvarado; R. Gielow; E. N. Lincoln; T. J. Christian; R. J. Yokelson; J. C. Santos

    2009-01-01

    Biomass consumption and CO2, CO and hydrocarbon gas emissions in an Amazonian forest clearing fire are presented and discussed. The experiment was conducted in the arc of deforestation, near the city of Alta Floresta, state of Mato Grosso, Brazil. The average carbon content of dry biomass was 48% and the estimated average moisture content of fresh biomass was 42% on...

  9. POLYCYCLIC AROMATIC HYDROCARBON EMISSION IN SPITZER/IRS MAPS. I. CATALOG AND SIMPLE DIAGNOSTICS

    Energy Technology Data Exchange (ETDEWEB)

    Stock, D. J.; Choi, W. D.-Y.; Moya, L. G. V.; Otaguro, J. N.; Sorkhou, S.; Peeters, E. [Department of Physics and Astronomy, University of Western Ontario, London, ON, N6A 3K7 (Canada); Allamandola, L. J. [NASA Ames Research Center, MS 245-6, Moffett Field, CA 94035-0001 (United States); Tielens, A. G. G. M., E-mail: dstock4@uwo.ca [Leiden Observatory, Leiden University, P.O. Box 9513, 2300 RA (Netherlands)

    2016-03-01

    We present a sample of resolved galactic H ii regions and photodissociation regions (PDRs) observed with the Spitzer infrared spectrograph in spectral mapping mode between the wavelengths of 5–15 μm. For each object we have spectral maps at a spatial resolution of ∼4″ in which we have measured all of the mid-infrared emission and absorption features. These include the polycyclic aromatic hydrocarbon (PAH) emission bands, primarily at 6.2, 7.7, 8.6, 11.2, and 12.7 μm, as well as the spectral emission lines of neon and sulfur and the absorption band caused by silicate dust at around 9.8 μm. In this work we describe the data in detail, including the data reduction and measurement strategies, and subsequently present the PAH emission band intensity correlations for each of the objects and the sample as a whole. We find that there are distinct differences between the sources in the sample, with two main groups: the first comprising the H ii regions and the second the reflection nebulae (RNe). Three sources—the reflection nebula NGC 7023, the Horsehead nebula PDR (an interface between the H ii region IC 434 and the Orion B molecular cloud), and M17—resist this categorization, with the Horsehead PDR points mimicking the RNe and the NGC 7023 fluxes displaying a unique bifurcated appearance in our correlation plots. These discrepancies seem to be due to the very low radiation field experienced by the Horsehead PDR and the very clean separation between the PDR environment and a diffuse environment in the NGC 7023 observations.

  10. Dioxins, furans and polycyclic aromatic hydrocarbons emissions from a hospital and cemetery waste incinerator

    Science.gov (United States)

    Mininni, Giuseppe; Sbrilli, Andrea; Maria Braguglia, Camilla; Guerriero, Ettore; Marani, Dario; Rotatori, Mauro

    An experimental campaign was carried out on a hospital and cemetery waste incineration plant in order to assess the emissions of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and polycyclic aromatic hydrocarbons (PAHs). Raw gases were sampled in the afterburning chamber, using a specifically designed device, after the heat recovery section and at the stack. Samples of slags from the combustion chamber and fly ashes from the bag filter were also collected and analyzed. PCDD/Fs and PAHs concentrations in exhaust gas after the heat exchanger (200-350 °C) decreased in comparison with the values detected in the afterburning chamber. Pollutant mass balance regarding the heat exchanger did not confirm literature findings about the de novo synthesis of PCDD/Fs in the heat exchange process. In spite of a consistent reduction of PCDD/Fs in the flue gas treatment system (from 77% up to 98%), the limit of 0.1 ng ITEQ Nm -3 at the stack was not accomplished. PCDD/Fs emission factors for air spanned from 2.3 up to 44 μg ITEQ t -1 of burned waste, whereas those through solid residues (mainly fly ashes) were in the range 41-3700 μg ITEQ t -1. Tests run with cemetery wastes generally showed lower PCDD/F emission factors than those with hospital wastes. PAH total emission factors (91-414 μg kg -1 of burned waste) were in the range of values reported for incineration of municipal and industrial wastes. In spite of the observed release from the scrubber, carcinogenic PAHs concentrations at the stack (0.018-0.5 μg Nm -3) were below the Italian limit of 10 μg Nm -3.

  11. Emission factors for carbonaceous particles and polycyclic aromatic hydrocarbons from residential coal combustion in China.

    Science.gov (United States)

    Chen, Yingjun; Sheng, Guoying; Bi, Xinhui; Feng, Yanli; Mai, Bixian; Fu, Jiamo

    2005-03-15

    Emission factors of carbonaceous particles, including black carbon (BC) and organic carbon (OC), and polycyclic aromatic hydrocarbons (PAHs) were determined for five coals, which ranged in maturity from sub-bituminous to anthracite. They were burned in the form of honeycomb briquettes in a residential coalstove, one of the most common fuel/stove combinations in China. Smoke samples were taken through dilution sampling equipment, with a high volume sampler that could simultaneously collect emissions in both particulate and gaseous phases, and a cascade impactor that could segregate particles into six fractions. Particulate BC and OC were analyzed by a thermal-optical method, and PAHs in emissions of both phases were analyzed by GC-MS. Burning of bituminous coals produced the highest emission factors of particulate matter (12.91 g/kg), BC (0.28 g/kg), OC (7.82 g/kg), and 20 PAHs (210.6 mg/kg) on the basis of burned dry ash-free (daf) coal, while the anthracite honeycomb-briquette was the cleanest household coal fuel. The size-segregated results show that more than 94% of the particles were submicron, and calculated mass median aerodynamic diameters (MMAD) of all particles were under 0.3 microm. Based on the coal consumption in the residential sector of China, 290.24 Gg (gigagrams) of particulate matter, 5.36 Gg of BC, 170.33 Gg of OC, and 4.72 Gg of 20 PAHs mass were emitted annually from household honeycomb-briquette burning during 2000. Anthracite coal should be selected preferentially and more advanced burning conditions should be applied in domestic combustion, from the viewpoint of both climate change and adverse health effects.

  12. Time resolved spectra in the infrared absorption and emission from shock heated hydrocarbons. [in interstellar medium

    Science.gov (United States)

    Bauer, S. H.; Borchardt, D. B.

    1990-01-01

    The wavelength range of a previously constructed multichannel fast recording spectrometer was extended to the mid-infrared. With the initial configuration, light intensities were recorded simultaneously with a silicon-diode array simultaneously at 20 adjacent wavelengths, each with a 20-micron time resolution. For studies in the infrared, the silicon diodes were replaced by a 20-element PbSe array of similar dimensions, cooled by a three-stage thermoelectric device. It is proposed that infrared emissions could be due to shock-heated low molecular-weight hydrocarbons. The full Swan band system appeared in time-integrated emission spectra from shock-heated C2H2; no soot was generated. At low resolution, the profiles on the high-frequency side of the black body maximum show no distinctive features. These could be fitted to Planck curves, with temperatures that declined with time from an initial high that was intermediate between T5 (no conversion) and T5(eq).

  13. Decentralized production of hydrogen from hydrocarbons with reduced CO{sub 2} emission

    Energy Technology Data Exchange (ETDEWEB)

    Nazim Muradov; Franklyn Smith; Cunping Huang; Ali T-Raissi [Florida Solar Energy Center, University of Central Florida, Cocoa, Florida, (United States)

    2006-07-01

    Currently, most of the industrial hydrogen production is based on steam methane reforming process that releases significant amount of CO{sub 2} into the atmosphere. CO{sub 2} sequestration is one approach to solving the CO{sub 2} emission problem for large centralized hydrogen plants, but it would be impractical for decentralized H{sub 2} production units. The objective of this paper is to explore new routes to hydrogen production from natural gas without (or drastically reduced) CO{sub 2} emissions. One approach analyzed in this paper is based on thermo-catalytic decomposition (TCD) of hydrocarbons (e.g., methane) to hydrogen gas and elemental carbon. The paper discusses some technological aspects of the TCD process development: (1) thermodynamic analysis of TCD using AspenPlus chemical process simulator, (2) heat input options to the endothermic process, (3) catalyst activity issues, etc. Production of hydrogen and carbon via TCD of methane was experimentally verified using carbon-based catalysts. (authors)

  14. Hydrocarbons peaks at Weybourne: What role do natural gas emissions play in the regional background?

    Science.gov (United States)

    Jacob, M. J.; Fleming, Z. L.; Monks, P. S.; Hulse, A.; Oram, D.; Bandy, B. J.; Penkett, S. A.; Hamilton, J. F.; Hopkins, J. R.

    2009-04-01

    Detailed chemical measurements were carried out during the TORCH II (Tropospheric ORganic CHemistry Experiment) campaign at the Weybourne Atmospheric Observatory on the north coast of Norfolk, UK in May 2004. On a number of occasions, large short-lived concentrations of alkenes were observed that correlated with CO, acetaldehyde, HCHO and some alkanes. Foremost was propene, which indicated to have come from emissions from oil and natural gas industries in the North Sea. Simultaneously, a sharp increase in peroxy radicals was observed (from ozone alkene reactions that also produced secondary species such as alkyl nitrates) and subsequent ozone destruction. These emission events were marked by O3 reduction with no corresponding NOy peaks but with extremely high levels of alkene and alkyl nitrates, implying the formation of large levels of peroxy radicals, leading to oxidation consequences in this clean marine environment. Steady state modelling to calculate OH and RO2 values during the episodes revealed that the only source of such high OH and ROx was the ozonolysis of propene. An air mass origin study linked the hydrocarbon peaks with northerly air masses, over the path of known North Sea oil and gas fields. Analysis of VOC measurements at Weybourne during the past 15 years reveals the frequency of such VOC spikes and the impact they could have on photochemical ozone production when they to occur during the daytime and ozone-alkene reactions at nighttime.

  15. Polycyclic aromatic hydrocarbons (PAHs) from coal combustion: emissions, analysis, and toxicology.

    Science.gov (United States)

    Liu, Guijian; Niu, Zhiyuan; Van Niekerk, Daniel; Xue, Jian; Zheng, Liugen

    2008-01-01

    Coal may become more important as an energy source in the 21st century, and coal contains large quantities of organic and inorganic matter. When coal burns chemical and physical changes take place, and many toxic compounds are formed and emitted. Polycyclic aromatic hydrocarbons (PAHs) are among those compounds formed and are considered to pose potential health hazards because some PAHs are known carcinogens. Based on their toxicology, 16 PAHs are considered as priority pollutants by the USEPA. More attention must be given to the various methods of extraction and analysis of PAH from coal or coal products to accurately explain and determine the species of PAHs. The influences of the extraction time, solvents, and methods for PAH identification are important. In the future, more methods and influences will be studied more carefully and widely. PAHs are environmental pollutants, are highly lipid soluble, and can be absorbed by the lungs, gut, and skin of mammals because they are associated with fine particles from coal combustion. More attention is being given to PAHs because of their carcinogenic and mutagenic action. We suggest that when using a coal stove indoors, a chimney should be used; the particles and gas containing PAHs should be released outdoors to reduce the health hazard, especially in Southwest China. During coal utilization processes, such as coal combustion and pyrolysis, PAHs released may be divided into two categories according to their formation pathways: one pathway is derived from complex chemical reactions and the other is from free PAHs transferred from the original coal. The formation and emission of PAHs is a complex physical and chemical process that has received considerable attention in recent years. It is suggested that the formation mechanisms of PAHs will be an increasingly important topic for researchers to find methods for controlling emissions during coal combustion.

  16. Emissions of polyciclic aromatic hydrocarbons and polyciclic carbonyl biphenils from electric arc furnaces

    Directory of Open Access Journals (Sweden)

    P. Gomes, J. F.

    2008-06-01

    Full Text Available This paper describes work done in order to determine the emissions of highly toxic organic micropollutants from electric arc furnaces used in the production of carbon steel from scrap. The study will be allowing to derive relationships between the levels of airborne micropollutants and the operational parameters of the production process so that an abatement of pollution could be achieved. By using the European standard method CEN 1948 for dioxin like compounds sampling and measurement, it was possible to determine the characteristic fingerprint of micropollutants such as polyciclic aromatic hydrocarbons (PAHs and polycyclic carbonyl biphenils (PCBs emitted by this particular stationary source.

    Este artículo contiene resultados del trabajo ejecutado para estudiar la determinación de las emisiones de los micropolutantes orgánicos muy tóxicos que se emiten por los hornos eléctricos de arco utilizados en la producción de acero. Este estudio inicial va a permitir relacionar las concentraciones de polutantes emitidos a la atmósfera con las condiciones de operación del horno eléctrico de arco. Utilizando el método normalizado CEN 1948 para captación y análisis de muestras de compuestos análogos a las dioxinas ha sido posible determinar el perfil característico de los micropolutantes tales como PAHs y PCBs emitidos por esta fuente.

  17. Severe aromatic hydrocarbon pollution in the Arctic town of Longyearbyen (Svalbard) caused by snowmobile emissions.

    Science.gov (United States)

    Reimann, Stefan; Kallenborn, Roland; Schmidbauer, Norbert

    2009-07-01

    The aromatic hydrocarbons benzene, toluene and C2-benzenes (ethyl benzene and m,p,o-xylene) (BTEX) were measured during a 2-month monitoring campaign in 2007 in the Arctic town of Longyearbyen (Spitsbergen, Svalbard). Reflecting the remoteness of the location, very low mixing ratios were observed during night and in windy conditions. In late spring (April-May), however, the high frequency of guided snowmobile tours resulted in "rush-hour" maximum values of more than 10 ppb of BTEX. These concentration levels are comparable to those in European towns and are caused predominately by the outdated 2-stroke engines, which are still used by approximately 30% of the snowmobiles in Longyearbyen. During summer, peak events were about a factor of 100 lower compared to those during the snowmobile season. Emissions in summer were mainly caused by diesel-fueled heavy duty vehicles (HDVs), permanently used for coal transport from the adjacent coal mines. The documented high BTEX mixing ratios from snowmobiles in the Arctic provide an obvious incentive to change the regulation practice to a cleaner engine technology.

  18. Hydrocarbon emissions and characterization of methane sources in the Barnett Shale

    Science.gov (United States)

    Marrero, J. E.; Townsend-Small, A.; Meinardi, S.; Blake, D. R.

    2014-12-01

    As energy demand and costs continue to rise worldwide, so does the development of energy from natural gas. The United States in particular has expanded its natural gas industry, becoming one of the world's top gas producing countries. The Barnett Shale of northern Texas is one of the most developed and productive natural gas shale plays in the United States. However, emissions from the many oil and gas system components in the region have not been fully characterized. An extensive list of volatile organic compounds (VOCs) was measured from 120 whole air canisters collected throughout the Barnett shale in October 2013. Known methane sources were targeted and included oil and natural gas well pads, compressor stations, distribution pipelines and city gates, cattle feedlots and landfills. C1-C5 alkanes were elevated throughout the region and were similar to or greater than concentrations in major U.S. cities. The VOC source signature for oil and gas operations was distinguished from biogenic sources. Average ethane content relative to methane was calculated for each of the source types, and ranged from 0.7 to 12.8%. For the whole region, the ethane content was 7.2±6.1%, illustrating the high variability and effect of the various hydrocarbon sources on the local air.

  19. The effects of biodiesel and its blends with diesel oil on the emission of volatile aromatic hydrocarbons

    Directory of Open Access Journals (Sweden)

    Adam Prokopowicz

    2013-12-01

    Full Text Available Background: In recent times, the emphasis is placed on the use of renewable fuels as well as biodiesel as an attractive alternative to conventional diesel fuel. Due to the fact that the impact of biodiesel on various chemical compounds exhaust emissions is not completely characterized, we have evaluated the emissions of volatile aromatic hydrocarbons in relation to biodiesel content in conventional diesel fuel. Material and methods: In the study we have assessed the emission of benzene, toluene, ethylbenzene and xylens during New European Driving Cycle NEDC for a passenger car with a diesel engine using the following fuels: 100% diesel fuel (B0, 100% rapeseed methyl esters (B100, 7, 15 and 30% rapeseed methyl esters in diesel fuel (B7, B15, B30, and 30% hydrotreated vegetable oil in diesel fuel (HVO30. Results: Among all determined compounds, benzene and toluene were emitted in the largest quantities. Higher emissions were determined during urban driving cycle then during extraurban driving cycle. A clear trend was observed when along with increasing amount of added rapeseed methyl esters the emission increased. However, additive of HVO decreased the emission of the most volatile aromatic compounds even when compared to conventional diesel fuel. During extra-urban driving cycle the emission was significantly lower and comparable for most fuels tested. Nevertheless in the context of conventional diesel fuel, lower emission for fuels with biodiesel was observed. Conclusion: The results have indicated the increase in benzene and toluene exhaust emissions mostly during urban driving cycle and its decrease during extra-urban driving cycle in NEDC test with increasing content of fatty acids methyl esters in diesel fuel. The emission in urban cycle was probably influenced by cold-start condition during this cycle. Generation of volatile aromatic hydrocarbons may be related to higher density of fuel with biodiesel in comparison to density of diesel oil

  20. The relationship between gasoline composition and vehicle hydrocarbon emissions: a review of current studies and future research needs.

    Science.gov (United States)

    Schuetzle, D; Siegl, W O; Jensen, T E; Dearth, M A; Kaiser, E W; Gorse, R; Kreucher, W; Kulik, E

    1994-01-01

    The purpose of this paper is to review current studies concerning the relationship of fuel composition to vehicle engine-out and tail-pipe emissions and to outline future research needed in this area. A number of recent combustion experiments and vehicle studies demonstrated that reformulated gasoline can reduce vehicle engine-out, tail-pipe, running-loss, and evaporative emissions. Some of these studies were extended to understand the fundamental relationships between fuel composition and emissions. To further establish these relationships, it was necessary to develop advanced analytical methods for the qualitative and quantitative analysis of hydrocarbons in fuels and vehicle emissions. The development of real-time techniques such as Fourier transform infrared spectroscopy, laser diode spectroscopy, and atmospheric pressure ionization mass spectrometry were useful in studying the transient behavior of exhaust emissions under various engine operating conditions. Laboratory studies using specific fuels and fuel blends were carried out using pulse flame combustors, single- and multicylinder engines, and vehicle fleets. Chemometric statistical methods were used to analyze the large volumes of emissions data generated from these studies. Models were developed that were able to accurately predict tail-pipe emissions from fuel chemical and physical compositional data. Some of the primary fuel precursors for benzene, 1,3-butadiene, formaldehyde, acetaldehyde and C2-C4 alkene emissions are described. These studies demonstrated that there is a strong relationship between gasoline composition and tail-pipe emissions. PMID:7529705

  1. The use Na, Li, K cations for modification of ZSM-5 zewolite to control hydrocarbon cold-start emission

    Energy Technology Data Exchange (ETDEWEB)

    Golubeva V.; Rohatgi U.; Korableva, A.; Anischenko, O.; Kustov, L.; Nissenbaum, V; Viola, M.B.

    2012-08-29

    This paper addresses the problem of controlling hydrocarbon emissions from cold-start of engines by investigating the adsorbents which could adsorb the hydrocarbons at cold temperatures and hold them to 250-300 ?. The materials, that has been studied, are based on the modification of ZSM-5 (SiO{sub 2}/Al{sub 2}O{sub 3} = 35) zeolite with Li, K, Na cations. It has been shown that the introduction of Li, Na and K in an amount that is equivalent to the content of Al in zeolite results in occurrence of toluene temperature desorption peaks at high-temperatures. The toluene temperature desorption curves for 5%Li-ZSM-5 and 2.3%Na-ZSM-5 zeolites are identical and have peak toluene desorption rate between 200 to 400 ?. Upon analysis of toluene adsorption isotherms for 2.3%Na-ZSM-5 and 5%Li-ZSM-5, it was concluded that the toluene diffusion inside of the modified zeolites channels is extremely slow and the sorption capacity of 2.3%Na-ZSM-5 is higher than with 5%Li-ZSM-5. The 2.3%Na-ZSM-5 didn't change toluene temperature programmed desorption (TPD) rate of curve after the treatment in environment with 10% ?{sub 2}? at 750-800 ? for about 28 h. The 2.3%Na-ZSM-5 zeolite is very promising as adsorbent to control the cold-start hydrocarbon emissions.

  2. Black carbon and polycyclic aromatic hydrocarbon emissions from vehicles in the United States-Mexico border region: pilot study.

    Science.gov (United States)

    Kelly, Kerry; Wagner, David; Lighty, JoAnn; Quintero Núñez, Margarito; Vazquez, F Adrian; Collins, Kimberly; Barud-Zubillaga, Alberto

    2006-03-01

    The investigators developed a system to measure black carbon (BC) and particle-bound polycyclic aromatic hydrocarbon (PAH) emission factors during roadside sampling in four cities along the United States-Mexico border, Calexico/Mexicali and El Paso/Juarez. The measurement system included a photoacoustic analyzer for BC, a photoelectric aerosol sensor for particle-bound PAHs, and a carbon dioxide (CO2) analyzer. When a vehicle with measurable emissions passed the system probe, corresponding BC, PAH, and CO2 peaks were evident, and a fuel-based emission factor was estimated. A picture of each vehicle was also recorded with a digital camera. The advantage of this system, compared with other roadside methods, is the direct measurement of particulate matter components and limited interference from roadside dust. The study revealed some interesting trends: Mexican buses and all medium-duty trucks were more frequently identified as high emitters of BC and PAH than heavy-duty trucks or passenger vehicles. In addition, because of the high daily mileage of buses, they are good candidates for additional study. Mexican trucks and buses had higher average emission factors compared with U.S. trucks and buses, but the differences were not statistically significant. Few passenger vehicles had measurable BC and PAH emissions, although the highest emission factor came from an older model passenger vehicle licensed in Baja California.

  3. Economic implications of incorporating emission controls to mitigate air pollutants emitted from a modeled hydrocarbon-fuel biorefinery in the United States: Economic implications of air emission controls for a hydrocarbon-fuel biorefinery

    Energy Technology Data Exchange (ETDEWEB)

    Bhatt, Arpit [National Renewable Energy Laboratory, Golden CO USA; Zhang, Yimin [National Renewable Energy Laboratory, Golden CO USA; Davis, Ryan [National Renewable Energy Laboratory, Golden CO USA; Eberle, Annika [National Renewable Energy Laboratory, Golden CO USA; Heath, Garvin [National Renewable Energy Laboratory, Golden CO USA

    2016-07-15

    The implementation of the US Renewable Fuel Standard is expected to increase the construction and operation of new biofuel facilities. Allowing this industry to grow without adversely affecting air quality is an important sustainability goal sought by multiple stakeholders. However, little is known about how the emission controls potentially required to comply with air quality regulations might impact biorefinery cost and deployment strategies such as siting and sizing. In this study, we use a baseline design for a lignocellulosic hydrocarbon biofuel production process to assess how the integration of emission controls impacts the minimum fuel selling price (MFSP) of the biofuel produced. We evaluate the change in MFSP for two cases as compared to the baseline design by incorporating (i) emission controls that ensure compliance with applicable federal air regulations and (ii) advanced control options that could be used to achieve potential best available control technology (BACT) emission limits. Our results indicate that compliance with federal air regulations can be achieved with minimal impact on biofuel cost (~$0.02 per gasoline gallon equivalent (GGE) higher than the baseline price of $5.10 GGE-1). However, if air emissions must be further reduced to meet potential BACT emission limits, the cost could increase nontrivially. For example, the MFSP could increase to $5.50 GGE-1 by adopting advanced emission controls to meet potential boiler BACT limits. Given tradeoffs among emission control costs, permitting requirements, and economies of scale, these results could help inform decisions about biorefinery siting and sizing and mitigate risks associated with air permitting.

  4. Efficiency Analysis of Technological Methods for Reduction of NOx Emissions while Burning Hydrocarbon Fuels in Heat and Power Plants

    Directory of Open Access Journals (Sweden)

    S. Kabishov

    2013-01-01

    Full Text Available The paper contains a comparative efficiency analysis pertaining to application of existing technological methods for suppression of nitric oxide formation in heating boilers of heat generators. A special attention has been given to investigation of NOx  emission reduction while burning hydrocarbon fuel with the help of oxygen-enriched air. The calculations have demonstrated that while enriching oxidizer with the help of oxygen up to 50 % (by volume it is possible to reduce volume of NOx formation (while burning fuel unit by 21 %.

  5. The HC generative subsystems of productive Mexican basins

    Energy Technology Data Exchange (ETDEWEB)

    Holguin, Noel; Galindo, Federico; Serrano, Emrique; Romero, Anunziata; Sosa, Alejandro; Martinez, Gustavo; Roman, Rogelio [Pemex Exploracion y Produccion (Mexico)

    1995-12-31

    There are six hydrocarbon producing basins in Mexico, these are from north to south: Sabinas, Burgos, Tampico-Misantla, Veracruz, Sureste, and Sierra de Chiapas. Better understanding and greater new insight into the petroleum systems of Mexico have been gained from extensive field research - more than 40,000 samples have been analyzed by Rock-Eval pyrolysis and, then the data interpreted; added to the information obtained from chromatography and, to a lesser degree from carbon isotope testing, biological marker and other types of analytical testing - made it possible not only to characterize the source rocks, but also determine with a high degree of exactness the origins of many of the hydrocarbons HC in Mexico, and also allowed a better understanding of the petroleum systems in Mexico. (author). 2 refs

  6. Particulate Emissions Hazards Associated with Fueling Heat Engines

    Directory of Open Access Journals (Sweden)

    Robert C. Hendricks

    2011-01-01

    Full Text Available All hydrocarbon- (HC- fueled heat engine exhaust (tailpipe emissions (<10 to 140 nm contribute as health hazards, including emissions from transportation vehicles (e.g., aircraft and other HC-fueled power systems. CO2 emissions are tracked and, when mapped, show outlines of major transportation routes and cities. Particulate pollution affects living tissue and is found to be detrimental to cardiovascular and respiratory systems where ultrafine particulates directly translocate to promote vascular system diseases potentially detectable as organic vapors. This paper discusses aviation emissions, fueling, and certification issues, including heat engine emissions hazards, detection at low levels and tracking of emissions, and alternate energy sources for general aviation.

  7. PAH emission from Herbig AeBe stars: Do hydrocarbons in proto-planetary disks have a unique aroma?

    Science.gov (United States)

    Keller, Luke; Sloan, Greg

    2008-03-01

    Over half of the intermediate-mass young stellar objects in the Galaxy (e.g. Herbig AeBe stars or HAeBe) have high-contrast emission in the mid-infrared spectral features of polycyclic aromatic hydrocarbons (PAHs) above the continuum produced by thermal emission from dust in the circumstellar disks. We have examined the PAH emission in detail for a sample of 19 HAeBe stars observed with the Spitzer IRS as part of the IRS Disks GTO program. Even with this relatively small sample, we have identified some trends that, should they survive in a larger sample of HAeBe stars, will allow us to infer large-scale disk geometry (both inner and outer) and the degree of photo-processing of organic molecular material in HAeBe disks. The bottom line of our work thus far is that HAeBe apparently have distinctive PAH spectra among the many other astronomical environments that are characterized by strong PAH emission. We therefore propose to apply our spectral analysis methods to an additional 57 HAeBe observed with the IRS and currently (or soon to be) available in the Spitzer archive. Our total sample of 76 HAeBe stars will allow closer scrutiny of the trends that we have identified in our empirical study and will also be the subject of a detailed disk modeling effort that will include the PAH emission.

  8. PAH Emission from Disks around Intermediate-Mass Stars: The Peculiar Aroma of Hydrocarbons Orbiting Herbig Ae/Be Stars

    Science.gov (United States)

    Keller, L. D.; Sloan, G. C.

    2009-12-01

    Over half of the intermediate-mass young stellar objects in the Galaxy (e.g. Herbig Ae/Be stars or HAeBe) have high-contrast emission in the mid-infrared spectral features of polycyclic aromatic hydrocarbons (PAHs) above the continuum produced by thermal emission from dust in the circumstellar disks. We have examined the PAH emission in detail for 30 HAeBe stars observed with the Spitzer IRS. We have identified some trends that, should they survive in a larger sample of HAeBe stars, will allow us to infer large-scale disk geometry (both inner and outer) and the degree of photo-processing of organic molecular material in HAeBe disks: HAeBe stars apparently have distinctive PAH spectra among the many other astronomical environments that are characterized by strong PAH emission; strong PAH emission is not necessarily an indicator of a particular disk geometry; PAH spectra of HAeBe stars change systematically with stellar effective temperature; PAH in HAeBe disks are ionized. As part of a Spitzer archival project we are applying our spectral analysis methods to an even larger sample of HAeBe stars observed with the IRS and currently available in the Spitzer archive. Here we report preliminary results as we begin the larger study.

  9. Estimating Emissions of Toxic Hydrocarbons from Natural Gas Production Sites in the Barnett Shale Region of Northern Texas.

    Science.gov (United States)

    Marrero, Josette E; Townsend-Small, Amy; Lyon, David R; Tsai, Tracy R; Meinardi, Simone; Blake, Donald R

    2016-10-04

    Oil and natural gas operations have continued to expand and move closer to densely populated areas, contributing to growing public concerns regarding exposure to hazardous air pollutants. During the Barnett Shale Coordinated Campaign in October, 2013, ground-based whole air samples collected downwind of oil and gas sites revealed enhancements in several potentially toxic volatile organic compounds (VOCs) when compared to background values. Molar emissions ratios relative to methane were determined for hexane, benzene, toluene, ethylbenzene, and xylene (BTEX compounds). Using methane leak rates measured from the Picarro mobile flux plane (MFP) system and a Barnett Shale regional methane emissions inventory, the rates of emission of these toxic gases were calculated. Benzene emissions ranged between 51 ± 4 and 60 ± 4 kg h(-1). Hexane, the most abundantly emitted pollutant, ranged from 642 ± 45 to 1070 ± 340 kg h(-1). While observed hydrocarbon enhancements fall below federal workplace standards, results may indicate a link between emissions from oil and natural gas operations and concerns about exposure to hazardous air pollutants. The larger public health risks associated with the production and distribution of natural gas are of particular importance and warrant further investigation, particularly as the use of natural gas increases in the United States and internationally.

  10. A Cache Timing Analysis of HC-256

    DEFF Research Database (Denmark)

    Zenner, Erik

    2009-01-01

    In this paper, we describe a cache-timing attack against the stream cipher HC-256, which is the strong version of eStream winner HC-128. The attack is based on an abstract model of cache timing attacks that can also be used for designing stream ciphers. From the observations made in our analysis,...

  11. Emission of polycyclic aromatic hydrocarbons from coal and sewage sludge co-combustion in a drop tube furnace.

    Science.gov (United States)

    Han, Jun; Qin, Linbo; Ye, Wei; Li, Yuqi; Liu, Long; Wang, Hao; Yao, Hong

    2012-09-01

    The emission characteristics of polycyclic aromatic hydrocarbons (PAHs) during coal and sewage sludge co-combustion were investigated in a laboratory-scale drop tube furnace. The experimental results demonstrated that coal and sewage sludge co-combustion was beneficial in reducing PAH emissions and PAH toxic equivalent (TEQ) concentrations. Meanwhile, the five-ring PAHs were the main contributor in reducing the concentration of PAHs and TEQ. Moreover, the two- and five-ring PAH concentrations decreased as the mass fraction of sewage sludge in the mixture increased from 0% to 100%. It was also found that PAHs from coal mono-combustion was dominated by the four- and five-ring PAHs. As for the sewage sludge mono-combustion, the three- and four-ring PAHs were the principal components.

  12. Diesel emission control: Catalytic filters for particulate removal

    Directory of Open Access Journals (Sweden)

    Debora Fino

    2007-01-01

    Full Text Available The European diesel engine industry represents a vital sector across the Continent, with more than 2 million direct work positions and a turnover of over 400 billion Euro. Diesel engines provide large paybacks to society since they are extensively used to transport goods, services and people. In recent years increasing attention has been paid to the emissions from diesel engines which, like gasoline engine emissions, include carbon monoxide (CO, hydrocarbons (HC and oxides of nitrogen (NOx. Diesel engines also produce significant levels of particulate matter (PM, which consists mostly of carbonaceous soot and a soluble organic fraction (SOF of hydrocarbons that have condensed on the soot.

  13. The bulk isotopic composition of hydrocarbons in subaerial volcanic-hydrothermal emissions from different tectonic settings

    Science.gov (United States)

    Fiebig, J.; Tassi, F.; Vaselli, O.; Viveiros, M. F.; Silva, C.; Lopez, T. M.; D'Alessandro, W.; Stefansson, A.

    2015-12-01

    Assuming that methane and its higher chain homologues derive from a common source, carbon isotope patterns have been applied as a criterion to identify occurrences of abiogenic hydrocarbons. Based on these, it has been postulated that abiogenic hydrocarbon production occurs within several (ultra)mafic environments. More evolved volcanic-hydrothermal systems may also provide all the prerequisites necessary for abiogenic hydrocarbon production, such as availability of inorganic CO2, hydrogen and heat. We have investigated the chemical and isotopic composition of n-alkanes contained within subaerial hydrothermal discharges emitted from a range of hot spot, subduction and rift-related volcanoes to determine the origin of hydrocarbons in these systems. Amongst these are Nisyros (Greece), Vesuvio, Campi Flegrei, Ischia, Pantelleria and Vulcano (all Italy), Mt. Mageik and Trident (USA), Copahue (Argentina), Teide (Spain), Furnas and Fogo (Portugal). The carbon isotopic composition of methane emitted from these sites varies from -65 to -8‰ , whereas δ13C of ethane and propane exhibit a much narrower variation from -17‰ to -31‰. Methane that occurs most enriched in 13C is also characterized by relatively positive δD values ranging up to -80‰. Carbon isotope reversals between methane and ethane are only observed for locations exhibiting δ13C-CH4 values > -20‰, such as Teide, Pantelleria, Trident and Furnas. At Furnas, δ13C-CH4 varies by 50‰ within a relatively short distance of <50m between two vents, whereas δ13C-C2H6 varies by less than 2‰ only. For some of the investigated locations apparent carbon isotopic temperatures between methane and CO2 are in agreement with those derived from gas concentration geothermometers. At these locations methane, however seems to be in disequilibrium with ethane and propane. These findings imply that methane on the one hand and the C2+ hydrocarbons on the other hand often might derive from distinct sources.

  14. Characteristics of polycyclic aromatic hydrocarbons and their gas/particle partitioning from fugitive emissions in coke plants

    Science.gov (United States)

    Mu, Ling; Peng, Lin; Liu, Xiaofeng; Song, Chongfang; Bai, Huiling; Zhang, Jianqiang; Hu, Dongmei; He, Qiusheng; Li, Fan

    2014-02-01

    Coking is one of the most important emission sources of polycyclic aromatic hydrocarbons (PAHs) in China. However, there is little information available on the emission characteristics of PAHs from fugitive emission during coking, especially on the specific processes dominating the gas-particle partitioning of PAHs. In this study, emission characteristics and gas-particle partitioning of PAHs from fugitive emission in four typical coke plants (CPs) with different scales and techniques were investigated. The average concentrations of total PAHs from fugitive emission at CP2, CP3 and CP4 (stamp charging) were 146.98, 31.82, and 35.20 μg m-3, which were 13.38-, 2.90- and 3.20-fold higher, respectively, than those at CP1 (top charging, 10.98 μg m-3). Low molecular weight PAHs with 2-3 rings made up 75.3% of the total PAHs on average, and the contributions of particulate PAH to the total BaP equivalent concentrations (BaPeq) in each plant were significantly higher than the corresponding contributions to the total PAH mass concentrations. The calculated total BaPeq concentrations varied from 0.19 to 10.86 μg m-3 with an average of 3.14 μg m-3, and more efficient measures to control fugitive emission in coke plants should be employed to prevent or reduce the health risk to workers. Absorption into organic matter dominated the gas-particle partitioning for most of the PAHs including PhA, FluA, Chr, BbF, BkF and BaP, while adsorption on elemental carbon appeared to play a dominant role for AcPy, AcP and Flu.

  15. Urban air chemistry and diesel vehicles emissions: Quantifying small and big hydrocarbons by CIMS to improve emission inventories

    Science.gov (United States)

    Jobson, B. T.; Derstroff, B.; Edtbauer, A.; VanderSchelden, G. S.; Williams, J.

    2017-10-01

    Emissions from vehicles are a major source of volatile organic compounds (VOCs) in urban environments. Photochemical oxidation of VOCs emitted from vehicle exhaust contributes to O3 and PM2.5 formation, harmful pollutants that major urban areas struggle to control. How will a shift to a diesel engine fleet impact urban air chemistry? Diesel vehicles are a growing fraction of the passenger vehicle fleet in Europe as a result of a deliberate policy to reduce energy consumption and CO2 emissions from the transportation sector (Sullivan et al., 2004). In countries such as France the diesel passenger fleet was already ∼50% of the total in 2009, up from 20% in 1995. Dunmore et al. (2015) have recently inferred that in London, HO radical loss rates to organic compounds is dominated by diesel engine emissions. In the US, increasingly more stringent vehicles emission standards and requirement for improved energy efficiency means spark ignition passenger vehicle emissions have declined significantly over the last 20 years, resulting in the urban diesel fleet traffic (freight trucks) having a growing importance as a source of vehicle pollution (McDonald et al., 2013). The recent scandal involving a major car manufacturer rigging emission controls for diesel passenger cars is a reminder that real world emissions of VOCs from diesel engines are not well understood nor thoroughly accounted for in air quality modeling.

  16. Mobile Laboratory Measurements of Black Carbon and Polycyclic Aromatic Hydrocarbon Emissions in Mexico City: A New Method for Motor Vehicle Emission Inventory Calculations

    Science.gov (United States)

    Jiang, M.; Marr, L. C.; Dunlea, E.; Herndon, S.; Jayne, J.; Rogers, T.; Knighton, B.; Zavala, M.; Molina, L. T.; Molina, M. J.

    2004-12-01

    Aerosol black carbon (BC) and polycyclic aromatic hydrocarbons (PAHs) are two products of carbonaceous fuel combustion that are of major concern for urban air quality and global climate change. As part of the Mexico City Metropolitan Area field campaign in April 2003 (MCMA-2003), a mobile laboratory drove throughout the city and chased vehicles to measure pollutants in their exhaust emissions. The laboratory is a van designed and built by Aerodyne Research, Inc. and is equipped with a suite of gas and particle analyzers, including an aethalometer that measures BC and a photoemission aerosol sensor that measures particle-bound PAHs. The main goal of this research is to determine fuel-based emission factors, or the mass of BC and PAH emitted per volume of fuel burned, for Mexico City¡_s vehicle fleet. We can then calculate the megacity¡_s emission inventory of these compounds, which is important on both the urban and global scales. In previous analyses, the mobile laboratory has been used to target emissions from specific vehicles. While chasing events can be analyzed to obtain emission factors for specific vehicles, data from the entire time period while the lab is driving through the streets, whether chasing individual vehicles or not, can also provide valuable information about mobile source emissions. The laboratory continuously samples ambient air from an inlet at the front of the van, and it is always ¡°seeing¡± exhaust plumes from the vehicles around it. This ¡°macroscopic¡± approach that considers all vehicles on the road, similar to tunnel and remote sensing studies, complements the ¡°microscopic¡± approach that focuses on individual vehicles. We have developed a method that automatically identifies exhaust plumes and quantifies emission factors from data collected by the mobile lab. While 200 individual chasing events were identified during the field campaign, over 40,000 exhaust plume points were identified using the macroscopic approach. The

  17. Accumulation of polycyclic aromatic hydrocarbons (PAHs) on the spider webs in the vicinity of road traffic emissions.

    Science.gov (United States)

    Rybak, Justyna; Olejniczak, Teresa

    2014-02-01

    Studies focused on the possible use of spider webs as environmental pollution indicators. This was a first time ever attempt to use webs as indicators of polycyclic aromatic hydrocarbons (PAHs) pollution. The aim of the study was (a) to evaluate whether webs are able to accumulate PM-associated road traffic emissions and be analyzed for organic toxics such as PAHs, (b) to assess if the distance from emission sources could have an influence on the accumulation level of pollutants, and (c) to determine types of pollution sources responsible for a structure of monitoring data set. Webs of four species from the family Agelenidae were sampled for PAHs presence. Data from vehicle traffic sites (i.e., road tunnel, arterial surface road, underground parking) and from railway traffic sites (i.e., two railway viaducts) in the city of Wroclaw (Southwest of Poland) showed a significantly higher mean concentrations of PAHs than the reference site 1 (municipal water supply works). We also found a significant differences at sites differed by the distance from emission sources. The result of PCA analysis suggested three important sources of pollution. We conclude that spider webs despite of some limitations proved useful indicators of road traffic emissions; they could be even more reliable compared to use of bioindicators whose activity is often limited by a lack of water and sun.

  18. Vehicle fleet emissions of black carbon, polycyclic aromatic hydrocarbons, and other pollutants measured by a mobile laboratory in Mexico City

    Directory of Open Access Journals (Sweden)

    M. Jiang

    2005-01-01

    Full Text Available Black carbon (BC and polycyclic aromatic hydrocarbons (PAHs are of concern due to their effects on climate and health. The main goal of this research is to provide the first estimate of emissions of BC and particle-phase PAHs (PPAHs from motor vehicles in Mexico City. The emissions of other pollutants including carbon monoxide (CO, oxides of nitrogen (NOx, volatile organic compounds (VOCs, and particulate matter of diameter 2.5 μm and less (PM2.5 are also estimated. As a part of the Mexico City Metropolitan Area field campaign in April 2003 (MCMA-2003, a mobile laboratory was driven throughout the city. The laboratory was equipped with a comprehensive suite of gas and particle analyzers, including an aethalometer that measured BC and a photoionization aerosol sensor that measured PPAHs. While driving through traffic, the mobile lab continuously sampled exhaust plumes from the vehicles around it. We have developed a method of automatically identifying exhaust plumes, which are then used as the basis for calculation of fleet-average emissions. In the approximately 75 h of on-road sampling during the field campaign, we have identified ~30 000 exhaust measurement points that represent a variety of vehicle types and driving conditions. The large sample provides a basis for estimating fleet-average emission factors and thus the emission inventory. Motor vehicles in the Mexico City area are estimated to emit 1700±200 metric tons BC, 57±6 tons PPAHs, 1 190 000±40 000 tons CO, 120 000±3000 tons NOx, 240 000±50 000 tons VOCs, and 4400±400 tons PM2.5 per year, not including cold start emissions. The estimates for CO, NOx, and PPAHs may be low by up to 10% due to the slower response time of analyzers used to measure these species. Compared to the government's official motor vehicle emission inventory for the year 2002, the estimates for CO, NOx, VOCs, and PM2.5 are 38% lower, 23% lower, 27% higher, and 25% higher, respectively. The

  19. Moving towards Sustainability: Road Grades and On-Road Emissions of Heavy-Duty Vehicles—A Case Study

    Directory of Open Access Journals (Sweden)

    Wendan Zhang

    2015-09-01

    Full Text Available On-road vehicle emissions are one of the major sources of transport emissions. As a key design factor, road grades (or road slopes have significant effects on on-road vehicle emissions, particularly on Heavy-Duty Vehicles (HDVs. However, the research into the relationship between road grades and on-road vehicle emissions is very rare in China. Taking a road network in Taiyuan, China, as a study area, this paper explored the influences of road grades on carbon monoxide (CO, hydrocarbon (HC, and nitrogen oxide (NOx emissions of HDVs. Combining emissions data collected by Portable Emission Measurement System (PEMS with Vehicle Specific Power (VSP, we developed an emission rate model of HDVs. Then, we integrated it with the traffic simulation model VISSIM to attain the emissions of HDVs on nine scenarios differentiated by road grades. The results showed that the three emissions are found to be highly correlated to road grades, among which the CO emissions are most sensitive to the change of road grades and the HC emissions least. Compared to the emissions at 0% grade, the emissions at 4% grade will be boosted from 39.0% to 60.6%. The CO and NOx emissions increase with the road grades in all nine scenarios, while the variations of HC emissions in different scenarios were complicated. The findings of this research will provide insights for policy-makers, scholars, and practitioners into strategies for improving road design to reduce traffic emissions and develop sustainable transportation in China.

  20. ALMA measurements of the HNC and HC$_3$N distributions in Titan's atmosphere

    CERN Document Server

    Cordiner, M A; Teanby, N A; Serigano, J; Charnley, S B; Milam, S N; Mumma, M J; Irwin, P G J; Lis, D C; Villanueva, G; Paganini, L; Kuan, Y -J; Remijan, A J

    2014-01-01

    We present spectrally and spatially-resolved maps of HNC and HC$_3$N emission from Titan's atmosphere, obtained with the Atacama Large Millimeter Array (ALMA) on 2013 November 17. These maps show anisotropic spatial distributions for both molecules, with resolved emission peaks in Titan's northern and southern hemispheres. The HC$_3$N maps indicate enhanced concentrations of this molecule over the poles, consistent with previous studies of Titan's photochemistry and atmospheric circulation. Differences between the integrated flux distributions of HNC and HC$_3$N show that these species are not co-spatial. The observed spectral line shapes are consistent with HNC residing predominantly in the mesosphere and above (at altitudes $z$ greater than about 400 km), whereas HC$_3$N is abundant at a broader range of altitudes ($z\\approx70-500$ km). From spatial variations in the HC$_3$N line profile, the locations of the HC$_3$N emission peaks are shown to be variable as a function of altitude. The integrated emission ...

  1. Sverige i H.C. Andersens optik

    DEFF Research Database (Denmark)

    svendsen, erik

    2008-01-01

    Analyse af H.C. Andersens rejsebog I Sverrig (1851), læst som et krydsfelt mellem biedermeier, romantik og modernitet, som et krydsfelt mellem Ingemans natursværmeri og Østeds mere positivistiske approach til naturen.......Analyse af H.C. Andersens rejsebog I Sverrig (1851), læst som et krydsfelt mellem biedermeier, romantik og modernitet, som et krydsfelt mellem Ingemans natursværmeri og Østeds mere positivistiske approach til naturen....

  2. Nitric oxide-assisted atmospheric pressure corona discharge ionization for the analysis of automobile hydrocarbon emission species.

    Science.gov (United States)

    Dearth, M A; Komiski, T J

    1994-12-01

    Nitric oxide reagent gas has been found to improve the sensitivity and robustness of the atmospheric pressure corona discharge ionization (APCDI) process. Sensitivity has been increased by a factor of 20-100, depending on the compound, over APCDI without nitric oxide. The robustness (defined as the sensitivity to matrix interferences) of APCDI in the presence of water has been improved by a factor of 3 over normal APCDI. These improvements are due in part to a modification of the commercial inlet system and ionization chamber that allows the chamber and sample gases to be heated to 100 and 350°C, respectively. Nitric oxide was chosen as the reagent gas because of the variety and selectivity of its interaction with hydrocarbons with differing functional groups. Product ions of nitric oxide ionization and their subsequent tandem mass spectra are presented and discussed for selected alkanes; alkenes, alkylbenzenes, alcohols; aldehydes, and an ether. A tandem mass spectrometry (unique parent ion-daughter ion transition) method was developed to quantify compounds of specific interest in vehicle emissions. The absolute sensitivity for these compounds, under ideal conditions, was determined and ranges from 0.006 ppb for xylene (most sensitive) to 80 ppb for C8 (or larger) normal alkanes. Routine sensitivity for real-world samples was in the single parts per billion range for aromatic and olefinic species. Potential applications include the real-time, on-line monitoring of selected hydrocarbons in automobile exhaust.

  3. Polycyclic aromatic hydrocarbon emission profiles and removal efficiency by electrostatic precipitator and wetfine scrubber in an iron ore sintering plant

    Energy Technology Data Exchange (ETDEWEB)

    Ettore Guerriero; Antonina Lutri; Rosanna Mabilia; Maria Concetta Tomasi Sciano; Mauro Rotatori [Istituto sull' Inquinamento Atmosferico, Monterotondo Scalo (Italy). Consiglio Nazionale delle Ricerche

    2008-11-15

    A monitoring campaign of polychlorinated dibenzo-p-dioxins and dibenzofurans, polyaromatic hydrocarbons (PAHs), and polychlorinated biphenyl was carried out in an Italian iron ore sintering plant by sampling the combustion gases at the electrostatic precipitator (ESP) outlet, at the Wetfine scrubber (WS) outlet, and by collecting the ESP dust. Few data are available on these micropollutants produced in iron ore sintering plants, particularly from Italian plants. This study investigates the PAH emission profiles and the removal efficiency of ESPs and WS. PAHs were determined at the stack, ESP outlet flue gases, and in ESP dust to characterize the emission profiles and the performance of the ESP and the WS for reducing PAH emission. The 11 PAHs monitored are listed in the Italian legislative decree 152/2006. The mean total PAH sum concentration in the stack flue gases is 3.96 {mu}g/N m{sup 3}, in ESP outlet flue gases is 9.73 {mu}g/N m{sup 3}, and in ESP dust is 0.53 {mu}g/g. Regarding the emission profiles, the most abundant compound is benzo(b)fluoranthene, which has a relative low BaP toxic equivalency factors (TEF) value, followed by dibenzo(a,l)pyrene, which has a very high BaP(TEF) value. The emission profiles in ESP dust and in the flue gases after the ESP show some changes, whereas the fingerprint in ESP and stack flue gases is very similar. The removal efficiency of the ESP and of WS on the total PAH concentration is 5.2 and 59.5%, respectively. 2 figs., 5 tabs.

  4. Increase in polycyclic aromatic hydrocarbon (PAH) emissions due to briquetting: A challenge to the coal briquetting policy.

    Science.gov (United States)

    Chen, Yingjun; Zhi, Guorui; Feng, Yanli; Chongguo Tian; Bi, Xinhui; Li, Jun; Zhang, Gan

    2015-09-01

    Both China and UNEP recommend replacing raw coal chunks with coal briquettes in household sector as clean coal technology (CCT), which has been confirmed by the decreased emissions of particulate matter and black carbon. However, the clean effect has never been systematically checked by other pollutants like polycyclic aromatic hydrocarbons (PAHs). In this study, 5 coals with different geological maturities were processed as both chunks and briquettes and burned in 3 typical coal stoves for the measurement of emission factors (EFs) of particle-bound PAHs. It was found that the EFs of 16 parent PAHs, 26 nitrated PAHs, 6 oxygenated PAHs, and 8 alkylated PAHs for coal briquettes were 6.90 ± 7.89, 0.04 ± 0.03, 0.65 ± 0.40, and 72.78 ± 18.23 mg/kg, respectively, which were approximately 3.1, 3.7, 1.9, and 171 times those for coal chunks, respectively. Such significant increases in PAH emissions increased human health risk and challenged the policy of CCT. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. CO2 emission free co-generation of energy and ethylene in hydrocarbon SOFC reactors with a dehydrogenation anode.

    Science.gov (United States)

    Fu, Xian-Zhu; Lin, Jie-Yuan; Xu, Shihong; Luo, Jing-Li; Chuang, Karl T; Sanger, Alan R; Krzywicki, Andrzej

    2011-11-21

    A dehydrogenation anode is reported for hydrocarbon proton conducting solid oxide fuel cells (SOFCs). A Cu-Cr(2)O(3) nanocomposite is obtained from CuCrO(2) nanoparticles as an inexpensive, efficient, carbon deposition and sintering tolerant anode catalyst. A SOFC reactor is fabricated using a Cu-Cr(2)O(3) composite as a dehydrogenation anode and a doped barium cerate as a proton conducting electrolyte. The protonic membrane SOFC reactor can selectively convert ethane to valuable ethylene, and electricity is simultaneously generated in the electrochemical oxidative dehydrogenation process. While there are no CO(2) emissions, traces of CO are present in the anode exhaust when the SOFC reactor is operated at over 700 °C. A mechanism is proposed for ethane electro-catalytic dehydrogenation over the Cu-Cr(2)O(3) catalyst. The SOFC reactor also has good stability for co-generation of electricity and ethylene at 700 °C.

  6. Detection of HC/sup 17/O/sup +/ in Sagittarius B2

    Energy Technology Data Exchange (ETDEWEB)

    Guelin, M.; Cernicharo, J.; Linke, R.A.

    1982-12-15

    Line emission at 87.057 GHz attributed to the J = 1..-->..0 rotational transition of the formyl ion HC/sup 17/O/sup +/ has been detected in Sgr B2 (OH). The HC/sup 18/O/sup +//HC/sup 17/O/sup +/ abundance ratio found (3.1 +- 0.6) is lower than the terrestrial /sup 18/O//sup 17/O elemental abundance ratio (5.5) and agrees, within the errors, with the C/sup 18/O/C/sup 17/O and /sup 18/OH//sup 17/OH abundance ratios observed in that source.

  7. PROBLEMS WITH DETERMINATION OF FUGITIVE EMISSION OF POLYCYCLIC AROMATIC HYDROCARBONS FROM COKE OVEN BATTERY

    Directory of Open Access Journals (Sweden)

    Rafał Bigda

    2017-03-01

    Full Text Available Coke oven battery is complex and multifaceted facility in terms of air pollutant emissions. As far as stack or quenching tower does not cause major difficulties of emission measurement, the fugitive emission measurement from sources such as battery top elements (charging holes, ascension pipes or oven doors is still complicated and not fully solved problem. This article presents the discussion concerning main problems and errors likely to be made in particular stages of procedure of fugitive emissions characterization from coke oven battery (selection of sampling points, sampling itself, measurement of air velocity over battery top and laboratory analyses. In addition, results of concentrations measurements of selected substances characteristic for the coking process (naphthalene, anthracene, 4 PAHs and TSP originating from fugitive sources of coke oven battery and subjected to reporting under the E-PRTR are presented. The measurements were carried out on coke oven battery top in points selected on the basis of the preceding detailed air convection velocity measurements over battery top. Results of the velocity measurements were compared with results of numerical modelling using CFD software. The presented material is an attempt to cross-sectional presentation of issues related to the quantitative evaluation of fugitive emission from coke oven battery, discussed on the example of PAHs emission as a group of substances characteristic for coking of coal.

  8. Geographic variations in female breast cancer incidence in relation to ambient air emissions of polycyclic aromatic hydrocarbons.

    Science.gov (United States)

    Large, Courtney; Wei, Yudan

    2017-07-01

    A significant geographic variation of breast cancer incidence exists, with incidence rates being much higher in industrialized regions. The objective of the current study was to assess the role of environmental factors such as exposure to ambient air pollution, specifically carcinogenic polycyclic aromatic hydrocarbons (PAHs) that may be playing in the geographic variations in breast cancer incidence. Female breast cancer incidence and ambient air emissions of PAHs were examined in the northeastern and southeastern regions of the USA by analyzing data from the Surveillance, Epidemiology, and End Results (SEER) Program and the State Cancer Profiles of the National Cancer Institute and from the Environmental Protection Agency. Linear regression analysis was conducted to evaluate the association between PAH emissions and breast cancer incidence in unadjusted and adjusted models. Significantly higher age-adjusted incidence rates of female breast cancer were seen in northeastern SEER regions, when compared to southeastern regions, during the years of 2000-2012. After adjusting for potential confounders, emission densities of total PAHs and four carcinogenic individual PAHs (benzo[a]pyrene, dibenz[a,h]anthracene, naphthalene, and benzo[b]fluoranthene) showed a significantly positive association with annual incidence rates of breast cancer, with a β of 0.85 (p = 0.004), 58.37 (p = 0.010), 628.56 (p = 0.002), 0.44 (p = 0.041), and 77.68 (p = 0.002), respectively, among the northeastern and southeastern states. This study suggests a potential relationship between ambient air emissions of carcinogenic PAHs and geographic variations of female breast cancer incidence in the northeastern and southeastern US. Further investigations are needed to explore these interactions and elucidate the role of PAHs in regional variations of breast cancer incidence.

  9. Measuring Star-Formation Rates of AGNs and QSOs using a new calibration from Polycyclic Aromatic Hydrocarbon Emission

    Science.gov (United States)

    Papovich, Casey

    Understanding the coevolution of star-formation and supermassive black hole accretion is one of the key questions in galaxy formation theory. This relation is important for understanding why at present the mass in galaxy bulges (on scales of kpc) correlates so tightly with the mass of galaxy central supermassive blackholes (on scales of AU). Feedback from supermassive black hole accretion may also be responsible for heating or expelling cold gas from galaxies, shutting off the fuel for star-formation and additional black hole growth. Did bulges proceed the formation of black holes, or vice versa, or are they contemporaneous? Therefore, understanding the exact rates of star-formation and supermassive black hole growth, and how they evolve with time and galaxy mass has deep implications for how galaxies form. It has previously been nearly impossible to study simultaneously both star-formation and accretion onto supermassive black holes in galaxies because the emission from black hole accretion contaminates nearly all diagnostics of star-formation. The "standard" diagnostics for the star-formation rate (the emission from hydrogen, UV emission, midIR emission, far-IR emission, etc) are not suitable for measuring star-formation rates in galaxies with actively accreting supermassive blackholes. In this proposal, the researchers request NASA/ADP funding for an archival study using spectroscopy with the Spitzer Space Telescope to measure simultaneously the star-formation rate (SFR) and bolometric emission from accreting supermassive blackholes to understand the complex relation between both processes. The key to this study is that they will develop a new calibrator for SFRs in galaxies with active supermassive black holes based on the molecular emission from polycyclic aromatic hydrocarbons (PAHs), which emit strongly in the mid-IR (3 - 20 micron) and are very strong in spectra from the Spitzer Space Telescope. The PAH molecules exist near photo-dissociation regions, and

  10. Nine years of global hydrocarbon emissions based on source inversion of OMI formaldehyde observations

    Science.gov (United States)

    Bauwens, Maite; Stavrakou, Trissevgeni; Müller, Jean-François; De Smedt, Isabelle; Van Roozendael, Michel; van der Werf, Guido R.; Wiedinmyer, Christine; Kaiser, Johannes W.; Sindelarova, Katerina; Guenther, Alex

    2016-08-01

    As formaldehyde (HCHO) is a high-yield product in the oxidation of most volatile organic compounds (VOCs) emitted by fires, vegetation, and anthropogenic activities, satellite observations of HCHO are well-suited to inform us on the spatial and temporal variability of the underlying VOC sources. The long record of space-based HCHO column observations from the Ozone Monitoring Instrument (OMI) is used to infer emission flux estimates from pyrogenic and biogenic volatile organic compounds (VOCs) on the global scale over 2005-2013. This is realized through the method of source inverse modeling, which consists in the optimization of emissions in a chemistry-transport model (CTM) in order to minimize the discrepancy between the observed and modeled HCHO columns. The top-down fluxes are derived in the global CTM IMAGESv2 by an iterative minimization algorithm based on the full adjoint of IMAGESv2, starting from a priori emission estimates provided by the newly released GFED4s (Global Fire Emission Database, version 4s) inventory for fires, and by the MEGAN-MOHYCAN inventory for isoprene emissions. The top-down fluxes are compared to two independent inventories for fire (GFAS and FINNv1.5) and isoprene emissions (MEGAN-MACC and GUESS-ES). The inversion indicates a moderate decrease (ca. 20 %) in the average annual global fire and isoprene emissions, from 2028 Tg C in the a priori to 1653 Tg C for burned biomass, and from 343 to 272 Tg for isoprene fluxes. Those estimates are acknowledged to depend on the accuracy of formaldehyde data, as well as on the assumed fire emission factors and the oxidation mechanisms leading to HCHO production. Strongly decreased top-down fire fluxes (30-50 %) are inferred in the peak fire season in Africa and during years with strong a priori fluxes associated with forest fires in Amazonia (in 2005, 2007, and 2010), bushfires in Australia (in 2006 and 2011), and peat burning in Indonesia (in 2006 and 2009), whereas generally increased fluxes

  11. Influence of fuel composition on polycyclic aromatic hydrocarbon emissions from a fleet of in-service passenger cars

    Science.gov (United States)

    Lim, McKenzie C. H.; Ayoko, Godwin A.; Morawska, Lidia.; Ristovski, Zoran D.; Jayaratne, E. Rohan

    The composition of exhaust emissions from eight in-service passenger cars powered by liquefied petroleum gas (LPG) and unleaded petrol (ULP) were measured on a chassis dynamometer at two driving speeds (60 and 80 km h -1) with the aims of evaluating their polycyclic aromatic hydrocarbon (PAH) contents and investigating the effects of the type of fuel on vehicle performance, ambient air quality and associated health risks. Naphthalene, fluorene, phenanthrene, anthracene, pyrene, chrysene, benzo(a)anthracene and benzo(b)fluoranthene were the most prominent PAHs emitted by both ULP and LPG powered cars. The total emission factors of PAHs from LPG cars were generally lower than (but statistically comparable with) those of ULP cars. Similarly, the total BAP eq of the PAHs emitted by LPG cars were lower than those from ULP cars. Multi-criteria decision making (MCDM) methods showed that cars powered by LPG fuel performed better than those powered by ULP fuel in term of PAH levels. The implications of these observations on the advantages and disadvantages of using ULP and LPG fuels are discussed.

  12. Probing the Ionization States of Polycyclic Aromatic Hydrocarbons via the 15-20 {\\mu}m Emission Bands

    CERN Document Server

    Shannon, M J; Peeters, E

    2015-01-01

    We report new correlations between ratios of band intensities of the 15-20 {\\mu}m emission bands of polycyclic aromatic hydrocarbons (PAHs) in a sample of fifty-seven sources observed with Spitzer/IRS. This sample includes Large Magellanic Cloud point sources from the SAGE-Spec survey, nearby galaxies from the SINGS survey, two Galactic ISM cirrus sources and the spectral maps of the Galactic reflection nebulae NGC 2023 and NGC 7023. We find that the 16.4, 17.4 and 17.8 {\\mu}m band intensities are inter-correlated in all environments. In NGC 2023 and NGC 7023 these bands also correlate with the 11.0 and 12.7 {\\mu}m band intensities. The 15.8 {\\mu}m band correlates only with the 15-20 {\\mu}m plateau and the 11.2 {\\mu}m emission. We examine the spatial morphology of these bands and introduce radial cuts. We find that these bands can be spatially organized into three sets: the 12.7, 16.4 and 17.8 {\\mu}m bands; the 11.2, 15.8 {\\mu}m bands and the 15-18 {\\mu}m plateau; and the 11.0 and 17.4 {\\mu}m bands. We also f...

  13. Estimating emissions of toxic hydrocarbons from natural gas production sites in the Barnett Shale region

    Science.gov (United States)

    Marrero, J. E.; Townsend-Small, A.; Lyon, D. R.; Tsai, T.; Meinardi, S.; Blake, D. R.

    2015-12-01

    Throughout the past decade, shale gas operations have moved closer to urban centers and densely populated areas, contributing to growing public concerns regarding exposure to hazardous air pollutants (HAPs). These HAPs include gases like hexane, 1,3-butadiene and BTEX compounds, which can cause minor health effects from short-term exposure or possibly cancer due to prolonged exposure. During the Barnett Shale Coordinated Campaign in October, 2013, ground-based whole air samples revealed enhancements in several of these toxic volatile organic compounds (VOCs) downwind of natural gas well pads and compressor stations. Two methods were used to estimate the emission rate of several HAPs in the Barnett Shale. The first method utilized CH4 flux measurements derived from the Picarro Mobile Flux Plane (MFP) and taken concurrently with whole air samples, while the second used a CH4 emissions inventory developed for the Barnett Shale region. From these two approaches, the regional emission estimate for benzene (C6H6) ranged from 48 ± 16 to 84 ± 26 kg C6H6 hr-1. A significant regional source of atmospheric benzene is evident, despite measurement uncertainty and limited number of samples. The extent to which these emission rates equate to a larger public health risk is unclear, but is of particular interest as natural gas productions continues to expand.

  14. Theoretical modeling of infrared emission from neutral and charged polycyclic aromatic hydrocarbons. I.

    NARCIS (Netherlands)

    Bakes, ELO; Tielens, AGGM; Bauschlicher, CW

    2001-01-01

    Since the discovery of interstellar infrared emission features in the 3.3-12.7 mum wavelength range three decades ago, the carriers of these features have been the subject of much debate. Recent observational work with the Infrared Space Observatory, experimental work, and quantum chemical calculati

  15. Polycyclic Aromatic Hydrocarbon emission in Spitzer/IRS maps I: Catalog and simple diagnostics

    CERN Document Server

    Stock, D J; Moya, L G V; Otaguro, J N; Sorkhou, S; Allamandola, L J; Tielens, A G G M; Peeters, E

    2016-01-01

    We present a sample of resolved galactic HII regions and photodissociation regions (PDRs) observed with the Spitzer infrared spectrograph (IRS) in spectral mapping mode between the wavelengths of 5--15 $\\mu$m. For each object we have spectral maps at a spatial resolution of $\\sim$4" in which we have measured all of the mid-infrared emission and absorption features. These include the PAH emission bands, primarily at 6.2, 7.7, 8.6, 11.2 and 12.7 $\\mu$m, as well as the spectral emission lines of neon and sulfur and the absorption band caused by silicate dust at around 9.8 $\\mu$m. In this work we describe the data in detail, including the data reduction and measurement strategies, and subsequently present the PAH emission band intensity correlations for each of the objects and the sample as a whole. We find that there are distinct differences between the sources in the sample, with two main groups, the first comprising the HII regions and the second the reflection nebulae (RNe). Three sources, the reflection nebu...

  16. Decreasing polycyclic aromatic hydrocarbons emission from bitumen using alternative bitumen production process.

    Science.gov (United States)

    Rasoulzadeh, Y; Mortazavi, S B; Yousefi, A A; Khavanin, A

    2011-01-30

    In 1988, the National Institute for Occupational Safety and Health (NIOSH) recommended that bitumen fumes should also be considered a potential occupational carcinogen and management practices such as engineering controls should be implemented. Changing the production process of bitumen, as a source control method, was investigated in our study. For the first time, a novel alternative process was used to produce paving grade bitumen with decreased PAH emissions as well as improved bitumen performance grade (PG). Post-consumer latex and natural bitumen (NB) were used as additives to obtain 60/70 modified bitumen directly from the vacuum bottom (VB) without any need for air-blowing. The emissions were produced by a laboratory fume generation rig and were sampled and analyzed by GC-Mass and GC-FID as described in NIOSH method 5515. The PG of the resulting modified 60/70 bitumen in this study covers a wider range of climatic conditions and has higher total resistance against deformation than conventional 60/70 bitumen. The total PAH emissions from modified 60/70 bitumen (100.2619 ng/g) were decreased approximately to 50% of PAHs emitted from conventional 60/70 bitumen (197.696 ng/g). Therefore, it is possible to obtain modified bitumen with lower PAH emissions and better quality than conventional bitumen via additives and without air-blowing.

  17. Polycyclic aromatic hydrocarbon and particulate emissions from two-stage combustion of polystyrene: the effect of the primary furnace temperature.

    Science.gov (United States)

    Wang, J; Levendis, Y A; Richter, H; Howard, J B; Carlson, J

    2001-09-01

    A study is presented on laboratory-scale combustion of polystyrene (PS) to identify staged-combustion conditions that minimize emissions. Batch combustion of shredded PS was conducted in fixed beds placed in a bench-scale electrically heated horizontal muffle furnace. In most cases, combustion of the samples occurred by forming gaseous diffusion flames in atmospheric pressure air. The combustion effluent was mixed with additional air, and it was channeled to a second muffle furnace (afterburner) placed in series. Further reactions took place in the secondary furnace at a residence time of 0.7 s. The gas temperature of the primary furnace was varied in the range of 500-1,000 degrees C, while that of the secondary furnace was kept fixed at 1,000 degrees C. Sampling for CO, CO2, O2, soot, and unburned hydrocarbon emissions (volatile and semivolatile, by GC-MS) was performed at the exits of the two furnaces. Results showed that the temperature of the primary furnace, where PS gasifies, is of paramount importance to the formation and subsequent emissions of organic species and soot. Atthe lowesttemperatures explored, mostly styrene oligomers were identified at the outlet of the primary furnace, but they did not survive the treatment in the secondary furnace. The formation and emission of polycyclic aromatic hydrocarbons (PAH) and soot were suppressed. As the temperature in the first furnace was raised, increasing amounts of a wide range of both unsubstituted and substituted PAH containing up to at least seven condensed aromatic rings were detected. A similar trend was observed for total particulate yields. The secondary furnace treatment reduced the yields of total PAH, but it had an ambiguous effect on individual species. While most low molecular mass PAH were reduced in the secondary furnace, concentrations of some larger PAH increased under certain conditions. Thus, care in the selection of operating conditions of both the primary furnace (gasifier/ burner) and the

  18. Implications of changing urban and rural emissions on non-methane hydrocarbons in the Pearl River Delta region of China

    Science.gov (United States)

    Tang, J. H.; Chan, L. Y.; Chan, C. Y.; Li, Y. S.; Chang, C. C.; Wang, X. M.; Zou, S. C.; Barletta, Barbara; Blake, D. R.; Wu, Dui

    2008-05-01

    Guangzhou (GZ) is one of the highly industrialized and economically vibrant cities in China, yet it remains relatively understudied in terms of its air quality, which has become severely degraded. In this study, extensive air sampling campaigns had been conducted at GZ urban sites and in Dinghu Mountain (DM), a rural site, in the Pearl River Delta (PRD) during the spring of 2001 and 2005. Additionally, roadside and tunnel samples were collected in GZ in 2000 and 2005. Later, exhaust samples from liquefied petroleum gas (LPG)- and gasoline-fueled taxis were collected in 2006. All samples were analyzed for C2-C10 non-methane hydrocarbons (NMHCs). NMHC profiles showed significant differences in the exhaust samples between gasoline- and LPG-fueled taxis. Propane (47%) was the dominant hydrocarbon in the exhaust of the LPG-fueled taxis, while ethene (35%) was the dominant one in that of gasoline-fueled taxis. The use of LPG-fueled buses and taxis since 2003 and the leakage from these LPG-fueled vehicles were the major factors for the much higher level of propane in GZ urban area in 2005 compared to 2001. The mixing ratios of toluene, ethylbenzene, m/p-xylene and o-xylene decreased at the GZ and DM sites between 2001 and 2005, especially for toluene in GZ, despite the sharp increase in the number of registered motor vehicles in GZ. This phenomenon was driven in part by the closure of polluting industries as well as the upgrading of the road network in urban GZ and in part by the implementation of more stringent emission standards for polluting industries and motor vehicles in the PRD region.

  19. Generation rates and emission factors of particulate matter and particle-bound polycyclic aromatic hydrocarbons of incense sticks.

    Science.gov (United States)

    Lung, Shih-Chun Candice; Hu, Shu-Chuan

    2003-02-01

    The generation rates and emission factors of particulate matter and associated polycyclic aromatic hydrocarbons (PAHs) from incense burning were assessed in a laboratory setting. The differences among different segments of the same stick, among different sticks of the same kind of incense, and between two kinds of manually made Chih-Chen incense sticks (A and B) were evaluated. Joss sticks were burned inside a 44 cm long elutriator; personal environmental monitors fitted into the top of the elutriator were used to take PM2.5 and PM10 samples of incense smoke. Samples were analyzed for PAHs by gas chromatography-flame ionization Detector. It was found that particle and associated PAHs were generated approximately at 561 microg/min (geometric standard deviation (GSD) = 1.1) and 0.56 microg/min (GSD = 1.1) from Incense A, and at 661 microg/min (GSD = 1.7) and 0.46 microg/min (GSD = 1.3) from Incense B, respectively. One gram of Incense A emitted about 19.8 mg (GSD = 1.1) particulate matter and 17.1 microg (GSD = 1.2) particulate-phase PAHs, while one gram of Incense B produced around 43.6 mg (GSD = 1.1) of particles and 25.2 microg (GSD = 1.2) of particle-bound PAHs. There were significant differences in emissions between Incenses A and B, although they belong to the same class of incense. A 10-20% variability in emissions was observed in the main part of the manually produced stick, and a larger variation was found at both tips of the combustible part.

  20. Characteristics of hopanoid hydrocarbons in ambient PM₁₀ and motor vehicle emissions and coal ash in Taiyuan, China.

    Science.gov (United States)

    Han, Feng; Cao, Junji; Peng, Lin; Bai, Huiling; Hu, Dongmei; Mu, Ling; Liu, Xiaofeng

    2015-10-01

    Hopanoid hydrocarbon content in ambient particulate matter (PM) of less than or equal to 10 μm aerodynamic diameter (PM10) was sampled at seven sites representative of different functional districts, and measured by gas chromatography-mass spectrometry. 17α(H),21β(H)-hopane (C30αβ) and 17α(H),21β(H)-30-norhopane (C29αβ) were dominant in all samples. Hopanes in motor vehicle emissions from various fuel-type engines (gasoline, diesel and natural gas) and coal ash were qualitatively measured, and the amount of C30αβ was about two to three times greater than that of C29αβ. Distinct seasonal variations (winter/summer differences) were observed at higher concentrations (45.54-108.29 ng/m(3)) of total hopanes in winter and lower (2.59-28.26 ng/m(3)) in summer. There were also clear spatial variations of hopanes in Taiyuan, with samples with greater hopane concentrations in downtown areas, but less in summer. The spatial distribution reversed in winter. Distributions and relative abundances of selected hopanes from PM10 and source emissions indicated that in summer, vehicle exhaust was the dominant fossil fuel combustion source (C30αβ was >C29αβ), and that the contribution of coal combustion was slightly greater at suburban sites. However, the contribution of coal combustion sources increased significantly at all sites in winter, especially in suburban areas, where C29αβ exceeded C30αβ. Hopanoid indexes revealed a classification of vehicle exhaust and coal combustion emissions in PM10. The results imply that during rapid urbanization, it is crucial to strengthen the construction of infrastructure such as central heating in new city districts and to increase the use of natural gas instead of residential coal burning.

  1. Emissions of Polycyclic Aromatic Hydrocarbons from Natural Gas Extraction into Air.

    Science.gov (United States)

    Paulik, L Blair; Donald, Carey E; Smith, Brian W; Tidwell, Lane G; Hobbie, Kevin A; Kincl, Laurel; Haynes, Erin N; Anderson, Kim A

    2016-07-19

    Natural gas extraction, often referred to as "fracking", has increased rapidly in the United States in recent years. To address potential health impacts, passive air samplers were deployed in a rural community heavily affected by the natural gas boom. Samplers were analyzed for 62 polycyclic aromatic hydrocarbons (PAHs). Results were grouped based on distance from each sampler to the nearest active well. Levels of benzo[a]pyrene, phenanthrene, and carcinogenic potency of PAH mixtures were highest when samplers were closest to active wells. PAH levels closest to natural gas activity were comparable to levels previously reported in rural areas in winter. Sourcing ratios indicated that PAHs were predominantly petrogenic, suggesting that PAH levels were influenced by direct releases from the earth. Quantitative human health risk assessment estimated the excess lifetime cancer risks associated with exposure to the measured PAHs. At sites closest to active wells, the risk estimated for maximum residential exposure was 0.04 in a million, which is below the U.S. Environmental Protection Agency's acceptable risk level. Overall, risk estimates decreased 30% when comparing results from samplers closest to active wells to those farthest from them. This work suggests that natural gas extraction is contributing PAHs to the air, at levels that would not be expected to increase cancer risk.

  2. Cache Timing Analysis of HC-256

    DEFF Research Database (Denmark)

    Zenner, Erik

    2008-01-01

    In this paper, we describe an abstract model of cache timing attacks that can be used for designing ciphers. We then analyse HC-256 under this model, demonstrating a cache timing attack under certain strong assumptions. From the observations made in our analysis, we derive a number of design prin...

  3. SPATIALLY RESOLVED l-C{sub 3}H{sup +} EMISSION IN THE HORSEHEAD PHOTODISSOCIATION REGION: FURTHER EVIDENCE FOR A TOP-DOWN HYDROCARBON CHEMISTRY

    Energy Technology Data Exchange (ETDEWEB)

    Guzmán, V. V.; Öberg, K. I. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Pety, J. [Institut de Radioastronomie Millimétrique (IRAM), 300 rue de la Piscine, F-38406 Saint Martin d’Hères (France); Goicoechea, J. R. [Instituto de Ciencia de Materiales de Madrid (CSIC), E-28049 Cantoblanco, Madrid (Spain); Gerin, M. [LERMA, Observatoire de Paris, École Normale Supérieure, PSL Research University, CNRS, UMR8112, F-75014 Paris (France); Roueff, E. [Sorbonne Universités, UPMC Univ. Paris 06, UMR8112, LERMA, F-75005 Paris (France); Gratier, P., E-mail: vguzman@cfa.harvard.edu [Université de Bordeaux, LAB, UMR 5804, F-33270, Floirac (France)

    2015-02-20

    Small hydrocarbons, such as C{sub 2}H, C{sub 3}H, and C{sub 3}H{sub 2} are more abundant in photo-dissociation regions (PDRs) than expected based on gas-phase chemical models. To explore the hydrocarbon chemistry further, we observed a key intermediate species, the hydrocarbon ion l-C{sub 3}H{sup +}, in the Horsehead PDR with the Plateau de Bure Interferometer at high-angular resolution (6″). We compare with previous observations of C{sub 2}H and c-C{sub 3}H{sub 2} at similar angular resolution and new gas-phase chemical model predictions to constrain the dominant formation mechanisms of small hydrocarbons in low-UV flux PDRs. We find that at the peak of the HCO emission (PDR position), the measured l-C{sub 3}H{sup +}, C{sub 2}H, and c-C{sub 3}H{sub 2} abundances are consistent with current gas-phase model predictions. However, in the first PDR layers, at the 7.7 μm polycyclic aromatic hydrocarbon band emission peak, which are more exposed to the radiation field and where the density is lower, the C{sub 2}H and c-C{sub 3}H{sub 2} abundances are underestimated by an order of magnitude. At this position, the l-C{sub 3}H{sup +} abundance is also underpredicted by the model but only by a factor of a few. In addition, contrary to the model predictions, l-C{sub 3}H{sup +} peaks further out in the PDR than the other hydrocarbons, C{sub 2}H and c-C{sub 3}H{sub 2}. This cannot be explained by an excitation effect. Current gas-phase photochemical models thus cannot explain the observed abundances of hydrocarbons, in particular, in the first PDR layers. Our observations are consistent with a top-down hydrocarbon chemistry, in which large polyatomic molecules or small carbonaceous grains are photo-destroyed into smaller hydrocarbon molecules/precursors.

  4. Emissions of volatile hydrocarbons (VOC) during drying of sawdust; Utslaepp av laettflyktiga kolvaeten vid torkning av biobraenslen

    Energy Technology Data Exchange (ETDEWEB)

    Granstroem, Karin

    2001-08-01

    In the project 'Emissions of volatile hydrocarbons (VOC) during drying of sawdust' the identity, amount and composition of monoterpenes found in the drying medium of a fluidized bed drier drying sawdust from Norwegian spruce and Scotch pine has been determined. The energy efficiency of the drier has also been measured. The aim of this project was to reduce both emissions and energy required for drying, to minimize environmental and health hazards, and make drying more competitive. This would help our primary target group - small scale saw mills - to make use of the sawdust produced as a by- product by making pellets and briquettes. If the VOC remains in the sawdust its energy content will improve and therefore also its value as a fuel. The sawdust was dried to different moisture levels in a spouted bed drier at atmospheric pressure, using either recirculating or not recirculating drying medium with temperatures 140, 170 or 200 deg C. The emissions of VOC were measured using a flame ionization detector (FID) and the nature of the emissions analyzed with a gas chromatograph with mass spectrometric detector (GC-MS). The GC-MS data is reported as emitted substance per oven dry weight (odw). Experiments show that terpenes do not leave the sawdust in great amounts until it is dried to a moisture content (water/total weight) below 10%. When sawdust is dried to a predetermined moisture level, the terpene emissions increase when warmer incoming drying medium is used. The monoterpenes found in greatest amount are a-pinene, b-pinene, 3-carene, limonene and myrcene. y-terpinene was detected in emissions from pine but not from spruce. The relative amounts of different monoterpenes did not vary significantly with post-drying moisture content, but drying medium of higher temperature caused an increase in the relative amount of less volatile monoterpenes. The FID data is reported as concentration of VOC in the drying medium, and as weight VOC per odw. The concentration

  5. Purification of recombinant Chlamydia trachomatis histone H1-like protein Hc2, and comparative functional analysis of Hc2 and Hc1

    DEFF Research Database (Denmark)

    Pedersen, LB; Birkelund, Svend; Christiansen, Gunna

    1996-01-01

    The metabolically inactive developmental form of Chlamydia trachomatis, the elementary body, contains two very basic DNA-binding proteins with homology to eukaryotic histone H1. One of these, Hc1, is relatively well characterized and induces DNA condensation in vitro, whereas the other, Hc2......, Hc2 was found to strongly inhibit translation and transcription in vitro. Our results imply that DNA condensation is not the only function of Hc2....

  6. Purification of recombinant Chlamydia trachomatis histone H1-like protein Hc2, and comparative functional analysis of Hc2 and Hc1

    DEFF Research Database (Denmark)

    Pedersen, Lotte Bang; Birkelund, S; Christiansen, G

    1996-01-01

    The metabolically inactive developmental form of Chlamydia trachomatis, the elementary body, contains two very basic DNA-binding proteins with homology to eukaryotic histone H1. One of these, Hc1, is relatively well characterized and induces DNA condensation in vitro, whereas the other, Hc2......, Hc2 was found to strongly inhibit translation and transcription in vitro. Our results imply that DNA condensation is not the only function of Hc2. Udgivelsesdato: 1996-Apr...

  7. Influence of oil and gas emissions on ambient atmospheric non-methane hydrocarbons in residential areas of Northeastern Colorado

    Directory of Open Access Journals (Sweden)

    Chelsea R. Thompson

    2014-11-01

    Full Text Available Abstract The Northern Front Range (NFR region of Colorado has experienced rapid expansion of oil and gas extraction from shale and tight sands reservoirs in recent years due to advances in hydraulic fracturing technology, with over 25,000 wells currently in operation. This region has also been designated as a federal ozone non-attainment area by the U.S. EPA. High ozone levels are a significant health concern, as are potential health impacts from chronic exposure to primary emissions of non-methane hydrocarbons (NMHC for residents living near wells. From measurements of ambient atmospheric NMHC present in residential areas located in close proximity to wells in Erie, Colorado, we find that mean mole fractions of the C2–C5 alkanes are enhanced by a factor of 18–77 relative to the regional background, and present at higher levels than typically found in large urban centers. When combined with NMHC observations from downtown Denver and Platteville, it is apparent that these compounds are elevated across the NFR, with highest levels within the Greater Wattenberg Gas Field. This represents a large area source for ozone precursors in the NFR. The BTEX aromatic compounds in Erie were comparable to (e.g., benzene or lower than (e.g., toluene, ethylbenzene, xylene in large urban centers, however, benzene was significantly higher in Platteville, and within the range of chronic health-based exposure levels. An initial look at comparisons with data sets from previous years reveal that ambient levels for oil and gas-related NMHC in Erie, as well as further downwind in Boulder, have not decreased, but appear to have been increasing, despite tightening of emissions standards for the oil and gas industries in 2008.

  8. Study of NOx Emissions of S.I. Engine Fueled with Different Kinds of Hydrocarbon Fuels and Hydrogen

    Directory of Open Access Journals (Sweden)

    Qahtan A. Abass

    2010-01-01

    Full Text Available Liquefied petroleum gas (LPG, Natural gas (NG and hydrogen were used to operate spark ignition internal combustion engine Ricardo E6, to compare NOx emissions emitted from the engine, with that emitted from engine fueled with gasoline as a fuel.The study was done when engine operated at HUCR for gasoline, compared with its operation at HUCR for each fuel. Compression ratio, equivalence ratio and spark timing were studied at constant speed 25rps.The results appeared that NOx concentrations will be at maximum value in the lean side near the stoichiometric ratio, and reduced with moving away from this ratio for mixture at both sides, these concentrations were at its highest value when hydrogen used at CR=8:1, and got near to each other for the three hydrocarbon fuels used in the study, when the engine operated at HUCR for each fuel, but still hydrogen had maximum value, the main variable affect these concentrations was spark timing

  9. A New Star-Formation Rate Calibration from Polycyclic Aromatic Hydrocarbon Emission Features and Application to High Redshift Galaxies

    CERN Document Server

    Shipley, Heath V; Rieke, George H; Brown, Michael J I; Moustakas, John

    2016-01-01

    We calibrate the integrated luminosity from the polycyclic aromatic hydrocarbon (PAH) features at 6.2\\micron, 7.7\\micron\\ and 11.3\\micron\\ in galaxies as a measure of the star-formation rate (SFR). These features are strong (containing as much as 5-10\\% of the total infrared luminosity) and suffer minimal extinction. Our calibration uses \\spitzer\\ Infrared Spectrograph (IRS) measurements of 105 galaxies at $0 < z < 0.4$, infrared (IR) luminosities of $10^9 - 10^{12} \\lsol$, combined with other well-calibrated SFR indicators. The PAH luminosity correlates linearly with the SFR as measured by the extinction-corrected \\ha\\ luminosity over the range of luminosities in our calibration sample. The scatter is 0.14 dex comparable to that between SFRs derived from the \\paa\\ and extinction-corrected \\ha\\ emission lines, implying the PAH features may be as accurate a SFR indicator as hydrogen recombination lines. The PAH SFR relation depends on gas-phase metallicity, for which we supply an empirical correction for...

  10. Emission, distribution and toxicity of polycyclic aromatic hydrocarbons (PAHs) during municipal solid waste (MSW) and coal co-combustion.

    Science.gov (United States)

    Peng, Nana; Li, Yi; Liu, Zhengang; Liu, Tingting; Gai, Chao

    2016-09-15

    Emission and distribution characteristics of polycyclic aromatic hydrocarbons (PAHs) were investigated during municipal solid waste (MSW) and coal combustion alone and MSW/coal blend (MSW weight fraction of 25%) co-combustion within a temperature range of 500°C-900°C. The results showed that for all combustion experiments, flue gas occupied the highest proportion of total PAHs and fly ash contained more high-ring PAHs. Moreover, the 3- and 4-ring PAHs accounted for the majority of total PAHs and Ant or Phe had the highest concentrations. Compared to coal, MSW combustion generated high levels of total PAHs with the range of 111.28μg/g-10,047.22μg/g and had high toxicity equivalent value (TEQ). MSW/coal co-combustion generated the smallest amounts of total PAHs and had the lowest TEQ than MSW and coal combustion alone. Significant synergistic interactions occurred between MSW and coal during co-combustion and the interactions suppressed the formation of PAHs, especially hazardous high-ring PAHs and decreased the TEQ. The present study indicated that the reduction of the yield and toxicity of PAHs can be achieved by co-combustion of MSW and coal.

  11. Gas- and particle-phase distribution of polycyclic aromatic hydrocarbons in two-stroke, 50-cm 3 moped emissions

    Science.gov (United States)

    Spezzano, Pasquale; Picini, Paolo; Cataldi, Dario

    Gas- and particle-phase polycyclic aromatic hydrocarbons (PAHs) concentrations evaluated in the exhaust of 10 two-stroke, 50-cm 3 mopeds belonging to three different levels of emission legislation (EURO-0, EURO-1 and EURO-2) were used to assess the prevalent mechanism driving the gas/particle partitioning of PAHs in moped exhaust. Sampling was performed on a dynamometer bench both during the "cold-start" and the "hot" phases of the ECE-47 driving cycle. Gas and particulate phase PAHs were collected on polyurethane foam (PUF) plugs and 47-mm Pallflex T60A20 filters, respectively, under isokinetic conditions by using sampling probes inserted into the dilution tunnel of a Constant Volume Sampling - Critical Flow Venturi (CVS-CFV) system. The results show that semi-volatile PAHs were predominantly partitioned to the particle phase. The soluble organic fraction (SOF) of the collected particulates ranged between 72 and 98%. Measured total suspended particulate matter normalized partition coefficients ( Kp) were predicted within a factor of 3-5 by assuming absorption into the organic fraction according to a model developed by Harner and Bidleman [Harner, T., Bidleman, T.F., 1998. Octanol-air partition coefficient for describing particle/gas partitioning of aromatic compounds in urban air. Environmental Science & Technology 32, 1494-1502.]. This suggests that the gas/particle partitioning in moped exhaust is mainly driven by the high fraction of organic matter of the emitted particles and that absorption could be the main partitioning mechanism of PAHs.

  12. Hydrocarbon emissions from lean-burn natural gas engines. Kinetic modelling and visualization

    Energy Technology Data Exchange (ETDEWEB)

    Broe Bendtsen, A.

    1999-07-01

    Motivated by emissions of unburned fuel from natural gas engines, a detailed chemical kinetic model describing NO{sub x} sensitized oxidation of methane was developed. New methods for visualization of such complex models have been developed, based on chemometrics and explorative data analysis. They may find application in combustion chemistry and in atmospheric chemistry, where detailed kinetic models are widely used. The motivation of the project was the discovery of significant emissions of unburned fuel from natural gas engines. The thesis contains a brief summary of emission levels and the sources of these emissions. Results from experiments by the Danish Gas Technology Centre on a pilot scale engine showed that oxidation of methane may occur in an extended exhaust manifold. Based on these results experiments were initiated to obtain detailed knowledge of the governing oxidation chemistry in the exhaust manifold. A series of laboratory experiments showed that at a residence time of 200 ms the threshold temperature for oxidation of methane was lowered by 200 {kappa} from 1100 {kappa} to 900 {kappa} in the presence of NO or NO{sub 2}. Experiments with a residence time of 140 ms showed that the sensitizing effect of NO was related to a longer lag time, compared to effect of NO{sub 2}. The major product of oxidation from 900 {kappa} to 1100 {kappa} was CO. Published detailed chemical kinetic models were not able to describe these phenomena. It was attempted to modify existing kinetic models to describe this sensitization by estimation of reaction rates. A literature survey of various method for estimation of reaction rates is given, and one methods for estimation of reaction rates using Partial Least Squares regression is demonstrated, but only with moderate success. To obtain a better kinetic model, a conventional approach to the refinement of the kinetic model was assisted by visualization methods and explorative data analysis. Through this approach an existing

  13. Comparison of hydrocarbon yields in cotton from field grown vs. greenhouse grown plants

    Science.gov (United States)

    Four accession of cotton (SA-1181, 1403, 1419, and 2269) were grown both in field conditions and a greenhouse to compare the environmental effects on leaf biomass, % yield of hydrocarbons (HC), and total HC (g HC /g leaves) under natural and controlled (protected) conditions. Leaf biomass was simi...

  14. Emissions of polycyclic aromatic hydrocarbons (PAHs) from the pyrolysis of scrap tires

    Science.gov (United States)

    Chen, Shui-Jen; Su, Hung-Bin; Chang, Juu-En; Lee, Wen-Jhy; Huang, Kuo-Lin; Hsieh, Lien-Te; Huang, Yi-Chu; Lin, Wen-Yinn; Lin, Chih-Chung

    This work investigated the PAHs generated in a waste-tire pyrolysis process and the PAHs removal by a wet scrubber (WSB) and a flare. IND, DBA, and BaP were found to dominate in the powders of scrap tires before the pyrolysis. The PAHs in the carbon blacks formed in the pyrolysis were mainly 2-, 3-, 6-, and 7-ring PAHs. Nap was the most predominant water-phase PAH in the WSB effluent. About 40% of the water-phase total-PAHs in the WSB effluent were contributed by nine carcinogenic PAHs. NaP, IND, and COR displayed higher mean gas- and particulate-phase concentrations than the other PAHs in the flare exhaust. The mean removal efficiencies of individual PAHs, total-PAHs, and high carcinogenic BaP+IND+DBA were 39.1-90.4%, 76.2%, and 84.9%, respectively for the WSB. For the flare, the mean removal efficiencies of gaseous, particulate, and combined (gaseous+particulate) total-PAHs were 59.8%, 91.2%, and 66.8%, respectively, whereas the removal efficiencies were 91.0%, 80.1%, and 89.1%, respectively for the total-BaPeq. However, the gaseous BaA displayed a negative mean removal efficiency. The total PAH emission rate and factor estimated for the scrap tire pyrolysis plant were 42.3 g d -1 and 4.00 mg kg-tire -1, respectively.

  15. High emission reduction performance of a novel organic-inorganic composite filters containing sepiolite mineral nanofibers

    Science.gov (United States)

    Wang, Fei; Zhang, Hui; Liang, Jinsheng; Tang, Qingguo; Li, Yanxia; Shang, Zengyao

    2017-03-01

    In this work, a new organic-inorganic composite filter was prepared. The thickness, pore size, air permeability, bursting strength and microstructure were characterized systematically, proving that coatings had regulatory effect on filters physical properties. Benefitting from the distinct coatings containing 5% sepiolite nanofibers after five times dilution, the physical properties of corresponding air filter exhibits the most favorable performance and meet the standard of air filter. When used as fuel filter, it satisfies the fuel filter standard and achieves the best performance after six times dilution. The contrast test on engine emission was taken based on auto filters coated with/without as prepared nanofibers. An obvious decrease in the emission of carbon monoxide (CO), hydrocarbons (HC) and nitrogen oxide (NOx) can be observed after installation of composite filter on vehicles. Under the high idle condition, gasoline engine emission decreased by 8.13%, 11.35% and 44.91% for CO, HC and NOx, respectively. When tested in the low idle condition, engine emission reduced by 0.43%, 1.14% and 85.67% for CO, HC and NOx, respectively. The diesel engine emissions of CO, NOx and total amount of HC and NOx decreased by 32.26%, 3.28% and 4.66%, respectively. The results illustrate the composite installation exhibits satisfactory emission reduction effect.

  16. Motor vehicle fuel economy, the forgotten HC control stragegy?

    Energy Technology Data Exchange (ETDEWEB)

    Deluchi, M.; Wang, Quanlu; Greene, D.L.

    1992-06-01

    Emissions of hydrocarbons from motor vehicles are recognized as major contributors to ozone pollution in urban areas. Petroleum-based motor fuels contain volatile organic compounds (VOC) which, together with oxides of nitrogen, promote the formation of ozone in the troposphere via complex photochemical reactions. VOC emissions from the tailpipe and evaporation from the fuel and engine systems of highway vehicles are believed to account for about 40% of total VOC emissions in any region. But motor fuels also generate emissions throughout the fuel cycle, from crude oil production to refining, storage, transportation, and handling, that can make significant contributions to the total inventory of VOC emissions. Many of these sources of emissions are directly related to the quantity of fuel produced and handled throughout the fuel cycle. It is, therefore, reasonable to expect that a reduction in total fuel throughput might result in a reduction of VOC emissions. In particular, reducing vehicle fuel consumption by increasing vehicle fuel economy should reduce total fuel throughput, thereby cutting total emissions of VOCS. In this report we identify the sources of VOC emissions throughout the motor fuel cycle, quantify them to the extent possible, and describe their dependence on automobile and light truck fuel economy.

  17. Inner State Table of HC-128%HC-128的内部状态表

    Institute of Scientific and Technical Information of China (English)

    赵伟

    2014-01-01

    Stream cipher HC-128 , as a simplified version of HC-256 , is one of the seven sequential ci-phers facilitating the final triumphs of European eSTREAM project. HC-128,composed of two algorithms, i. e. initialization algorithm and generating key stream algorithm, is a software implementation algorithm based on table driving. Owing to its high security performance, there is,up to now,no effective analysis method. HC-128 takes advantage of the transition and selection of inner state table to construct sequential cipher, thus the security of inner state table has a direct influence on that of sequential cipher. Inner state table of HC-128 is analyzed,and algorithms of secret key and initialization vector are also presented in ac-cordance with inner state tables, P and Q ( each one with 512 bytes, tolalled up to 512 bytes) .%HC-128算法是HC-256算法的简化版,为欧洲eSTREAM工程最终胜出的7个序列密码算法之一。 HC-128由初始化算法和密钥流产生算法两部分构成,为基于表驱动的适于软件实现的算法。由于其安全性能高,至今未见有效的分析方法。 HC-128利用内部状态表的转换、选择来构造序列密码,因此内部状态表的安全性直接影响着序列密码算法的安全性。该文对HC-128的内部状态表进行了研究,给出了根据内部状态表P和Q(两个512字,共计1024字)倒推出密钥和初始向量的算法。

  18. A comparison on the emission of polycyclic aromatic hydrocarbons and their corresponding carcinogenic potencies from a vehicle engine using leaded and lead-free gasoline.

    Science.gov (United States)

    Mi, H H; Lee, W J; Tsai, P J; Chen, C B

    2001-12-01

    Our objective in this study was to assess the effect of using two kinds of lead-free gasoline [including 92-lead-free gasoline (92-LFG) and 95-lead-free gasoline (95-LFG), rated according to their octane levels] to replace the use of premium leaded gasoline (PLG) on the emissions of polycyclic aromatic hydrocarbons (PAHs) and their corresponding benzo[a]pyrene equivalent (BaP(eq)) amounts from the gasoline-powered engine. The results show that the three gasoline fuels originally contained similar total PAHs and total BaP(eq) contents; however, we found significant differences in the engine exhausts in both contents. The above results suggest that PAHs originally contained in the gasoline fuel did not affect the PAH emissions in the engine exhausts. The emission factors of both total PAHs and total BaP(eq) obtained from the three gasoline fuels shared the same trend: 95-LFG > PLG > 92-LFG. The above result suggests that when PLG was replaced by 95-LFG, the emissions would increase in both total PAHs and total BaP(eq), but when replaced by 92-LFG would lead to the decreased emissions of both contents. By taking emission factors and their corresponding annual gasoline consumption rates into account, we found that both total PAH and total BaP(eq) emissions increased from 1994 to 1999. However, the annual increasing rates in total BaP(eq) emissions were slightly higher than the corresponding increasing rates in total PAHs.

  19. Comparison of flexible fuel vehicle and life-cycle fuel consumption and emissions of selected pollutants and greenhouse gases for ethanol 85 versus gasoline.

    Science.gov (United States)

    Zhai, Haibo; Frey, H Christopher; Rouphail, Nagui M; Gonçalves, Gonçalo A; Farias, Tiago L

    2009-08-01

    The objective of this research is to evaluate differences in fuel consumption and tailpipe emissions of flexible fuel vehicles (FFVs) operated on ethanol 85 (E85) versus gasoline. Theoretical ratios of fuel consumption and carbon dioxide (CO2) emissions for both fuels are estimated based on the same amount of energy released. Second-by-second fuel consumption and emissions from one FFV Ford Focus fueled with E85 and gasoline were measured under real-world traffic conditions in Lisbon, Portugal, using a portable emissions measurement system (PEMS). Cycle average dynamometer fuel consumption and emission test results for FFVs are available from the U.S. Department of Energy, and emissions certification test results for ethanol-fueled vehicles are available from the U.S. Environmental Protection Agency. On the basis of the PEMS data, vehicle-specific power (VSP)-based modal average fuel and emission rates for both fuels are estimated. For E85 versus gasoline, empirical ratios of fuel consumption and CO2 emissions agree within a margin of error to the theoretical expectations. Carbon monoxide (CO) emissions were found to be typically lower. From the PEMS data, nitric oxide (NO) emissions associated with some higher VSP modes are higher for E85. From the dynamometer and certification data, average hydrocarbon (HC) and nitrogen oxides (NOx) emission differences vary depending on the vehicle. The differences of average E85 versus gasoline emission rates for all vehicle models are -22% for CO, 12% for HC, and -8% for NOx emissions, which imply that replacing gasoline with E85 reduces CO emissions, may moderately decrease NOx tailpipe emissions, and may increase HC tailpipe emissions. On a fuel life cycle basis for corn-based ethanol versus gasoline, CO emissions are estimated to decrease by 18%. Life-cycle total and fossil CO2 emissions are estimated to decrease by 25 and 50%, respectively; however, life-cycle HC and NOx emissions are estimated to increase by 18 and 82

  20. High-temperature CO / HC gas sensors to optimize firewood combustion in low-power fireplaces

    Directory of Open Access Journals (Sweden)

    B. Ojha

    2017-06-01

    Full Text Available In order to optimize firewood combustion in low-power firewood-fuelled fireplaces, a novel combustion airstream control concept based on the signals of in situ sensors for combustion temperature, residual oxygen concentration and residual un-combusted or partly combusted pyrolysis gas components (CO and HC has been introduced. A comparison of firing experiments with hand-driven and automated airstream-controlled furnaces of the same type showed that the average CO emissions in the high-temperature phase of the batch combustion can be reduced by about 80 % with the new control concept. Further, the performance of different types of high-temperature CO / HC sensors (mixed-potential and metal oxide types, with reference to simultaneous exhaust gas analysis by a high-temperature FTIR analysis system, was investigated over 20 batch firing experiments (∼ 80 h. The distinctive sensing behaviour with respect to the characteristically varying flue gas composition over a batch firing process is discussed. The calculation of the Pearson correlation coefficients reveals that mixed-potential sensor signals correlate more with CO and CH4; however, different metal oxide sensitive layers correlate with different gas species: 1 % Pt / SnO2 designates the presence of CO and 2 % ZnO / SnO2 designates the presence of hydrocarbons. In the case of a TGS823 sensor element, there was no specific correlation with one of the flue gas components observed. The stability of the sensor signals was evaluated through repeated exposure to mixtures of CO, N2 and synthetic air after certain numbers of firing experiments and exhibited diverse long-term signal instabilities.

  1. Emission and Combustion Characteristics of Si Engine Working Under Gasoline Blended with Ethanol Oxygenated Organic Compounds

    Directory of Open Access Journals (Sweden)

    Dhanapal Balaji

    2010-01-01

    Full Text Available Problem statement: The objective of this study is to investigate the effect of using unleaded gasoline and additives blends on Spark Ignition engine (SI engine combustion and exhaust emission. Approach: A four stroke, single cylinder SI engine was used for conducting this study. Exhaust emissions were analysed for Carbon Monoxide (CO, Hydrocarbon (HC and Oxides of Nitrogen (NOx and carbon dioxide (CO2 using unleaded gasoline and additives blends with different percentages of fuel at varying engine torque condition and constant engine speed. Results: The result showed that the blending of unleaded gasoline increases the octane number and power output this may leads to increase the brake thermal efficiency. The CO, HC and NOx emissions concentrations in the engine exhaust decreases while the CO2 concentration increases. Conclusion: Using ethanol as a fuel additive to unleaded gasoline causes an improvement in combustion characteristics and significant reduction in exhaust emissions.

  2. Speed-dependent emission of air pollutants from gasoline-powered passenger cars.

    Science.gov (United States)

    Jung, Sungwoon; Lee, Meehye; Kim, Jongchoon; Lyu, Youngsook; Park, Junhong

    2011-01-01

    In Korea emissions from motor vehicles are a major source of air pollution in metropolitan cities, and in Seoul a large proportion of the vehicle fleet is made up of gasoline-powered passenger cars. The carbon monoxide (CO), hydrocarbons (HC), oxides of nitrogen (NOx) and carbon dioxide (CO2) contained in the exhaust emissions from 76 gasoline-powered passenger cars equipped with three-way catalysts has been assessed by vehicle speed, vehicle mileage and model year. The results show that CO, HC, NOx and CO2 emissions remained almost unchanged at higher speeds but decreased rapidly at lower speeds. While a reduction in CO, HC and NOx emissions was noticeable in vehicles of recent manufacture and lower mileage, CO2 emissions were found to be insensitive to vehicle mileage, but strongly dependent on gross vehicle weight. Lower emissions from more recent gasoline-powered vehicles arose mainly from improvements in three-way catalytic converter technology following strengthened emission regulations. The correlation between CO2 emission and fuel consumption has been investigated with a view to establishing national CO2 emission standards for Korea.

  3. Polycyclic aromatic hydrocarbons and nitropolycyclic aromatic hydrocarbons in urban air particulates and their relationship to emission sources in the Pan-Japan Sea countries

    Energy Technology Data Exchange (ETDEWEB)

    Tang, N.; Hattori, T.; Taga, R.; Igarashi, K.; Yang, X.Y.; Tamura, K.; Kakimoto, H.; Mishukov, V.F.; Toriba, A.; Kizu, R.; Hayakawa, K. [Kanazawa University, Kanazawa (Japan)

    2005-10-01

    Airborne particulates were collected in seven cities in the Pan-Japan Sea countries, Shenyang (China), Vladivostok (Russia), Seoul (South Korea), Kitakyushu, Kanazawa, Tokyo and Sapporo (Japan), in winter and summer from 1997 to 2002. In addition, particulates from domestic coal-burning heaters and diesel engine automobiles were collected in Shenyang and Kanazawa, respectively. Nine polycyclic aromatic hydrocarbons (PAHs) and four nitropolycyclic aromatic hydrocarbons (NPAHs) in the extracts from the particulates were analysed by HPLC with fluorescence and chemiluminescence detections, respectively. Mean atmospheric concentrations of PAHs in Shenyang and Vladivostok were substantially higher than those in Seoul, Tokyo, Sapporo, Kitakyushu and Kanazawa. However, the mean atmospheric concentrations of NPAHs were at the same levels in all cities except Kitakyushu. The expected seasonal variations (greater PAH and NPAH concentrations in winter than in summer) were observed in all cities. In order to study the major contributors of atmospheric PAHs and NPAHs, both cluster analysis and factor analysis were used and three large clusters were identified. The 1-nitropyrene/pyrene concentration ratio seemed to be a suitable indicator of the contribution made by diesel-engine vehicles and coal combustion to urban air particulates.

  4. Hydrocarbon pneumonia

    Science.gov (United States)

    Pneumonia - hydrocarbon ... Coughing Fever Shortness of breath Smell of a hydrocarbon product on the breath Stupor (decreased level of ... Most children who drink or inhale hydrocarbon products and develop ... hydrocarbons may lead to rapid respiratory failure and death.

  5. Sources of hydrocarbons in sediments of the Mandovi estuary and the Marmugoa harbour, west coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    Harji, R.R.; Yvenat, A.; Bhosle, N.B.

    . The total HC concentrations, n-alkane composition, CPI, UCM and other evaluation indices suggest the dominance of terrestrial hydrocarbons in the estuarine while petroleum derived hydrocarbons in the harbour sediments. This conclusion was further supported...

  6. Comparison of global 3-D aviation emissions datasets

    Directory of Open Access Journals (Sweden)

    S. C. Olsen

    2013-01-01

    Full Text Available Aviation emissions are unique from other transportation emissions, e.g., from road transportation and shipping, in that they occur at higher altitudes as well as at the surface. Aviation emissions of carbon dioxide, soot, and water vapor have direct radiative impacts on the Earth's climate system while emissions of nitrogen oxides (NOx, sulfur oxides, carbon monoxide (CO, and hydrocarbons (HC impact air quality and climate through their effects on ozone, methane, and clouds. The most accurate estimates of the impact of aviation on air quality and climate utilize three-dimensional chemistry-climate models and gridded four dimensional (space and time aviation emissions datasets. We compare five available aviation emissions datasets currently and historically used to evaluate the impact of aviation on climate and air quality: NASA-Boeing 1992, NASA-Boeing 1999, QUANTIFY 2000, Aero2k 2002, and AEDT 2006 and aviation fuel usage estimates from the International Energy Agency. Roughly 90% of all aviation emissions are in the Northern Hemisphere and nearly 60% of all fuelburn and NOx emissions occur at cruise altitudes in the Northern Hemisphere. While these datasets were created by independent methods and are thus not strictly suitable for analyzing trends they suggest that commercial aviation fuelburn and NOx emissions increased over the last two decades while HC emissions likely decreased and CO emissions did not change significantly. The bottom-up estimates compared here are consistently lower than International Energy Agency fuelburn statistics although the gap is significantly smaller in the more recent datasets. Overall the emissions distributions are quite similar for fuelburn and NOx with regional peaks over the populated land masses of North America, Europe, and East Asia. For CO and HC there are relatively larger differences. There are however some distinct differences in the altitude distribution

  7. Comparison of global 3-D aviation emissions datasets

    Directory of Open Access Journals (Sweden)

    S. C. Olsen

    2012-07-01

    Full Text Available Aviation emissions are unique from other transportation emissions, e.g., from road transportation and shipping, in that they occur at higher altitudes as well as at the surface. Aviation emissions of carbon dioxide, soot, and water vapor have direct radiative impacts on the Earth's climate system while emissions of nitrogen oxides (NOx, sulfur oxides, carbon monoxide (CO, and hydrocarbons (HC impact air quality and climate through their effects on ozone, methane, and clouds. The most accurate estimates of the impact of aviation on air quality and climate utilize three-dimensional chemistry-climate models and gridded four dimensional (space and time aviation emissions datasets. We compare five available aviation emissions datasets currently and historically used to evaluate the impact of aviation on climate and air quality: NASA-Boeing 1992, NASA-Boeing 1999, QUANTIFY 2000, Aero2k 2002, and AEDT 2006 and aviation fuel usage estimates from the International Energy Agency. Roughly 90% of all aviation emissions are in the Northern Hemisphere and nearly 60% of all fuelburn and NOx emissions occur at cruise altitudes in the Northern Hemisphere. While these datasets were created by independent methods and are thus not strictly suitable for analyzing trends they suggest that commercial aviation fuelburn and NOx emissions increased over the last two decades while HC emissions likely decreased and CO emissions did not change significantly. The bottom-up estimates compared here are consistently lower than International Energy Agency fuelburn statistics although the gap is significantly lower in the more recent datasets. Overall the emissions distributions are quite similar for fuelburn and NOx while for CO and HC there are relatively larger differences. There are however some distinct differences in the altitude distribution of emissions in certain regions for the Aero2k dataset.

  8. Emissions from Diesel and Gasoline Vehicles Fuelled by Fischer-Tropsch Fuels and Similar Fuels

    DEFF Research Database (Denmark)

    Larsen, Ulrik; Lundorff, Peter; Ivarsson, Anders

    2007-01-01

    vehicles fuelled by Fischer Tropsch (FT) based diesel and gasoline fuel, compared to the emissions from ordinary diesel and gasoline. The comparison for diesel fuels was based on a literature review, whereas the gasoline comparison had to be based on our own experiments, since almost no references were...... and an alkylate fuel (Aspen), which was taken to be the ultimate formula of FT gasoline. FT based diesel generally showed good emission performance, whereas the FT based gasoline not necessary lead to lower emissions. On the other hand, the Aspen fuel did show many advantages for the emissions from the gasoline......The described investigation was carried out under the umbrella of IEA Advanced Motor Fuels Agreement. The purpose was to evaluate the emissions of carbon monoxide (CO), unburned hydrocarbons (HC), nitrogen oxides (NOx), particulate matter (PM) and polycyclic aromatic hydrocarbons (PAH) from...

  9. A comparison on the emission of polycyclic aromatic hydrocarbons and their corresponding carcinogenic potencies from a vehicle engine using leaded and lead-free gasoline.

    OpenAIRE

    Mi, H H; Lee, W J; Tsai, P.J.; Chen, C B

    2001-01-01

    Our objective in this study was to assess the effect of using two kinds of lead-free gasoline [including 92-lead-free gasoline (92-LFG) and 95-lead-free gasoline (95-LFG), rated according to their octane levels] to replace the use of premium leaded gasoline (PLG) on the emissions of polycyclic aromatic hydrocarbons (PAHs) and their corresponding benzo[a]pyrene equivalent (BaP(eq)) amounts from the gasoline-powered engine. The results show that the three gasoline fuels originally contained sim...

  10. Atmospheric emissions from the Deepwater Horizon spill constrain air-water partitioning, hydrocarbon fate, and leak rate

    Science.gov (United States)

    Ryerson, T. B.; Aikin, K. C.; Angevine, W. M.; Atlas, E. L.; Blake, D. R.; Brock, C. A.; Fehsenfeld, F. C.; Gao, R.-S.; de Gouw, J. A.; Fahey, D. W.; Holloway, J. S.; Lack, D. A.; Lueb, R. A.; Meinardi, S.; Middlebrook, A. M.; Murphy, D. M.; Neuman, J. A.; Nowak, J. B.; Parrish, D. D.; Peischl, J.; Perring, A. E.; Pollack, I. B.; Ravishankara, A. R.; Roberts, J. M.; Schwarz, J. P.; Spackman, J. R.; Stark, H.; Warneke, C.; Watts, L. A.

    2011-04-01

    The fate of deepwater releases of gas and oil mixtures is initially determined by solubility and volatility of individual hydrocarbon species; these attributes determine partitioning between air and water. Quantifying this partitioning is necessary to constrain simulations of gas and oil transport, to predict marine bioavailability of different fractions of the gas-oil mixture, and to develop a comprehensive picture of the fate of leaked hydrocarbons in the marine environment. Analysis of airborne atmospheric data shows massive amounts (˜258,000 kg/day) of hydrocarbons evaporating promptly from the Deepwater Horizon spill; these data collected during two research flights constrain air-water partitioning, thus bioavailability and fate, of the leaked fluid. This analysis quantifies the fraction of surfacing hydrocarbons that dissolves in the water column (˜33% by mass), the fraction that does not dissolve, and the fraction that evaporates promptly after surfacing (˜14% by mass). We do not quantify the leaked fraction lacking a surface expression; therefore, calculation of atmospheric mass fluxes provides a lower limit to the total hydrocarbon leak rate of 32,600 to 47,700 barrels of fluid per day, depending on reservoir fluid composition information. This study demonstrates a new approach for rapid-response airborne assessment of future oil spills.

  11. Modeling and Multi-Objective Optimization of Engine Performance and Hydrocarbon Emissions via the Use of a Computer Aided Engineering Code and the NSGA-II Genetic Algorithm

    Directory of Open Access Journals (Sweden)

    Richard Fiifi Turkson

    2016-01-01

    Full Text Available It is feared that the increasing population of vehicles in the world and the depletion of fossil-based fuel reserves could render transportation and other activities that rely on fossil fuels unsustainable in the long term. Concerns over environmental pollution issues, the high cost of fossil-based fuels and the increasing demand for fossil fuels has led to the search for environmentally friendly, cheaper and efficient fuels. In the search for these alternatives, liquefied petroleum gas (LPG has been identified as one of the viable alternatives that could be used in place of gasoline in spark-ignition engines. The objective of the study was to present the modeling and multi-objective optimization of brake mean effective pressure and hydrocarbon emissions for a spark-ignition engine retrofitted to run on LPG. The use of a one-dimensional (1D GT-Power™ model, together with Group Method of Data Handling (GMDH neural networks, has been presented. The multi-objective optimization was implemented in MATLAB® using the non-dominated sorting genetic algorithm (NSGA-II. The modeling process generally achieved low mean squared errors (0.0000032 in the case of the hydrocarbon emissions model for the models developed and was attributed to the collection of a larger training sample data using the 1D engine model. The multi-objective optimization and subsequent decisions for optimal performance have also been presented.

  12. HC/MC-130 Recapitalization Aircraft (HC/MC-130 Recap)

    Science.gov (United States)

    2015-12-01

    device for aircrew providing a practical experience in use of checklists, palletized loading, winching exercises, loading of vehicles, loading and...Apr 2010 Airworthiness Certification Complete Jan 2012 Dec 2011 Dec 2011 Dec 2011 Initiate IOT &E Mar 2012 Mar 2012 Mar 2012 Mar 2012 Required Assets...Acronyms and Abbreviations IOT &E - Initial Operational Test and Evaluation OT&E - Operational Test and Evaluation HC/MC-130 Recap December 2015 SAR

  13. Size-resolved polycyclic aromatic hydrocarbon emission factors from on-road gasoline and diesel vehicles: temperature effect on the nuclei-mode.

    Science.gov (United States)

    Eiguren-Fernandez, Arantzazu; Miguel, Antonio H

    2012-03-06

    Motor vehicles are a major source of polycyclic aromatic hydrocarbon (PAH) emissions in urban areas. Motor vehicle emission control strategies have included improvements in engine design, exhaust emission control, and fuel reformulation. Therefore, an updated assessment of the effects of the shifts in fuels and vehicle technologies on PAH vehicular emission factors (EFs) is needed. We have evaluated the effects of ambient temperature on the size-resolved EFs of nine US EPA Priority Pollutant PAH, down to 10 nm diameter, from on-road California gasoline light-duty vehicles with spark ignition (SI) and heavy-duty diesels with compression ignition (CI) in summer 2004 and winter 2005. During the winter, for the target PAH with the lowest subcooled equilibrium vapor pressure --benzo[a]pyrene, benzo[ghi]perylene, and indeno[1,2,3-cd]pyrene-- the mass in the nucleation mode, defined here as particles with dp <32 nm, ranged between 14 and 38% for SI vehicles and 29 and 64% for CI vehicles. Our observations of the effect of temperature on the mass of PAH in the nucleation mode are similar to the observed effect of temperature on the number concentration of diesel exhaust particles in the nucleation mode in a previous report.

  14. Estimation of the efficiency of hydrocarbon mineralization in soil by measuring CO2-emission and variations in the isotope composition of carbon dioxide

    Science.gov (United States)

    Dubrovskaya, Ekaterina; Turkovskaya, Olga

    2010-05-01

    Estimation of the efficiency of hydrocarbon mineralization in soil by measuring CO2-emission and variations in the isotope composition of carbon dioxide E. Dubrovskaya1, O. Turkovskaya1, A. Tiunov2, N. Pozdnyakova1, A. Muratova1 1 - Institute of Biochemistry and Physiology of Plants and Microorganisms, RAS, Saratov, 2 - A.N. Severtsov Institute of Ecology and Evolution, RAS, Moscow, Russian Federation Hydrocarbon mineralization in soil undergoing phytoremediation was investigated in a laboratory experiment by estimating the variation in the 13С/12С ratio in the respired СО2. Hexadecane (HD) was used as a model hydrocarbon pollutant. The polluted soil was planted with winter rye (Secale cereale) inoculated with Azospirillum brasilense strain SR80, which combines the abilities to promote plant growth and to degrade oil hydrocarbon. Each vegetated treatment was accompanied with a corresponding nonvegetated one, and uncontaminated treatments were used as controls. Emission of carbon dioxide, its isotopic composition, and the residual concentration of HD in the soil were examined after two and four weeks. At the beginning of the experiment, the CO2-emission level was higher in the uncontaminated than in the contaminated soil. After two weeks, the quantity of emitted carbon dioxide decreased by about three times and did not change significantly in all uncontaminated treatments. The presence of HD in the soil initially increased CO2 emission, but later the respiration was reduced. During the first two weeks, nonvegetated soil had the highest CO2-emission level. Subsequently, the maximum increase in respiration was recorded in the vegetated contaminated treatments. The isotope composition of plant material determines the isotope composition of soil. The soil used in our experiment had an isotopic signature typical of soils formed by C3 plants (δ13C,-22.4‰). Generally, there was no significant fractionation of the carbon isotopes of the substrates metabolized by the

  15. Observation of $h_{c}$ radiative decay $h_{c} \\rightarrow \\gamma \\eta'$ and evidence for $h_{c} \\rightarrow \\gamma \\eta$

    CERN Document Server

    Ablikim, M; Ai, X C; Albayrak, O; Albrecht, M; Ambrose, D J; Amoroso, A; An, F F; An, Q; Bai, J Z; Ferroli, R Baldini; Ban, Y; Bennett, D W; Bennett, J V; Bertani, M; Bettoni, D; Bian, J M; Bianchi, F; Boger, E; Boyko, I; Briere, R A; Cai, H; Cai, X; Cakir, O; Calcaterra, A; Cao, G F; Cetin, S A; Chang, J F; Chelkov, G; Chen, G; Chen, H S; Chen, H Y; Chen, J C; Chen, M L; Chen, S; Chen, S J; Chen, X; Chen, X R; Chen, Y B; Cheng, H P; Chu, X K; Cibinetto, G; Dai, H L; Dai, J P; Dbeyssi, A; Dedovich, D; Deng, Z Y; Denig, A; Denysenko, I; Destefanis, M; De Mori, F; Ding, Y; Dong, C; Dong, J; Dong, L Y; Dong, M Y; Dou, Z L; Du, S X; Duan, P F; Fan, J Z; Fang, J; Fang, S S; Fang, X; Fang, Y; Farinelli, R; Fava, L; Fedorov, O; Feldbauer, F; Felici, G; Feng, C Q; Fioravanti, E; Fritsch, M; Fu, C D; Gao, Q; Gao, X L; Gao, X Y; Gao, Y; Gao, Z; Garzia, I; Goetzen, K; Gong, L; Gong, W X; Gradl, W; Greco, M; Gu, M H; Gu, Y T; Guan, Y H; Guo, A Q; Guo, L B; Guo, R P; Guo, Y; Guo, Y P; Haddadi, Z; Hafner, A; Han, S; Hao, X Q; Harris, F A; He, K L; Held, T; Heng, Y K; Hou, Z L; Hu, C; Hu, H M; Hu, J F; Hu, T; Hu, Y; Huang, G S; Huang, J S; Huang, X T; Huang, X Z; Huang, Y; Huang, Z L; Hussain, T; Ji, Q; Ji, Q P; Ji, X B; Ji, X L; Jiang, L W; Jiang, X S; Jiang, X Y; Jiao, J B; Jiao, Z; Jin, D P; Jin, S; Johansson, T; Julin, A; Kalantar-Nayestanaki, N; Kang, X L; Kang, X S; Kavatsyuk, M; Ke, B C; Kiese, P; Kliemt, R; Kloss, B; Kolcu, O B; Kopf, B; Kornicer, M; Kupsc, A; Kühn, W; Lange, J S; Lara, M; Larin, P; Leng, C; Li, C; Li, Cheng; Li, D M; Li, F; Li, F Y; Li, G; Li, H B; Li, H J; Li, J C; Li, Jin; Li, K; Li, Lei; Li, P R; Li, Q Y; Li, T; Li, W D; Li, W G; Li, X L; Li, X N; Li, X Q; Li, Y B; Li, Z B; Liang, H; Liang, Y F; Liang, Y T; Liao, G R; Lin, D X; Liu, B; Liu, B J; Liu, C X; Liu, D; Liu, F H; Liu, Fang; Liu, Feng; Liu, H B; Liu, H H; Liu, H M; Liu, J; Liu, J B; Liu, J P; Liu, J Y; Liu, K; Liu, K Y; Liu, L D; Liu, P L; Liu, Q; Liu, S B; Liu, X; Liu, Y B; Liu, Z A; Liu, Zhiqing; Loehner, H; Lou, X C; Lu, H J; Lu, J G; Lu, Y; Lu, Y P; Luo, C L; Luo, M X; Luo, T; Luo, X L; Lyu, X R; Ma, F C; Ma, H L; Ma, L L; Ma, M M; Ma, Q M; Ma, T; Ma, X N; Ma, X Y; Ma, Y M; Maas, F E; Maggiora, M; Mao, Y J; Mao, Z P; Marcello, S; Messchendorp, J G; Min, J; Mitchell, R E; Mo, X H; Mo, Y J; Morales, C Morales; Muchnoi, N Yu; Muramatsu, H; Nefedov, Y; Nerling, F; Nikolaev, I B; Ning, Z; Nisar, S; Niu, S L; Niu, X Y; Olsen, S L; Ouyang, Q; Pacetti, S; Pan, Y; Patteri, P; Pelizaeus, M; Peng, H P; Peters, K; Pettersson, J; Ping, J L; Ping, R G; Poling, R; Prasad, V; Qi, H R; Qi, M; Qian, S; Qiao, C F; Qin, L Q; Qin, N; Qin, X S; Qin, Z H; Qiu, J F; Rashid, K H; Redmer, C F; Ripka, M; Rong, G; Rosner, Ch; Ruan, X D; Sarantsev, A; Savrié, M; Schoenning, K; Schumann, S; Shan, W; Shao, M; Shen, C P; Shen, P X; Shen, X Y; Sheng, H Y; Shi, M; Song, W M; Song, X Y; Sosio, S; Spataro, S; Sun, G X; Sun, J F; Sun, S S; Sun, X H; Sun, Y J; Sun, Y Z; Sun, Z J; Sun, Z T; Tang, C J; Tang, X; Tapan, I; Thorndike, E H; Tiemens, M; Ullrich, M; Uman, I; Varner, G S; Wang, B; Wang, B L; Wang, D; Wang, D Y; Wang, K; Wang, L L; Wang, L S; Wang, M; Wang, P; Wang, P L; Wang, S G; Wang, W; Wang, W P; Wang, X F; Wang, Y; Wang, Y D; Wang, Y F; Wang, Y Q; Wang, Z; Wang, Z G; Wang, Z H; Wang, Z Y; Weber, T; Wei, D H; Wei, J B; Weidenkaff, P; Wen, S P; Wiedner, U; Wolke, M; Wu, L H; Wu, L J; Wu, Z; Xia, L; Xia, L G; Xia, Y; Xiao, D; Xiao, H; Xiao, Z J; Xie, Y G; Xiu, Q L; Xu, G F; Xu, J J; Xu, L; Xu, Q J; Xu, Q N; Xu, X P; Yan, L; Yan, W B; Yan, W C; Yan, Y H; Yang, H J; Yang, H X; Yang, L; Yang, Y X; Ye, M; Ye, M H; Yin, J H; Yu, B X; Yu, C X; Yu, J S; Yuan, C Z; Yuan, W L; Yuan, Y; Yuncu, A; Zafar, A A; Zallo, A; Zeng, Y; Zeng, Z; Zhang, B X; Zhang, B Y; Zhang, C; Zhang, C C; Zhang, D H; Zhang, H H; Zhang, H Y; Zhang, J; Zhang, J J; Zhang, J L; Zhang, J Q; Zhang, J W; Zhang, J Y; Zhang, J Z; Zhang, K; Zhang, L; Zhang, S Q; Zhang, X Y; Zhang, Y; Zhang, Y H; Zhang, Y N; Zhang, Y T; Zhang, Yu; Zhang, Z H; Zhang, Z P; Zhang, Z Y; Zhao, G; Zhao, J W; Zhao, J Y; Zhao, J Z; Zhao, Lei; Zhao, Ling; Zhao, M G; Zhao, Q; Zhao, Q W; Zhao, S J; Zhao, T C; Zhao, Y B; Zhao, Z G; Zhemchugov, A; Zheng, B; Zheng, J P; Zheng, W J; Zheng, Y H; Zhong, B; Zhou, L; Zhou, X; Zhou, X K; Zhou, X R; Zhou, X Y; Zhu, K; Zhu, K J; Zhu, S; Zhu, S H; Zhu, X L; Zhu, Y C; Zhu, Y S; Zhu, Z A; Zhuang, J; Zotti, L; Zou, B S; Zou, J H

    2016-01-01

    A search for radiative decays of the $P$-wave spin singlet charmonium resonance $h_c$ is performed based on $4.48 \\times 10^{8}$ $\\psi'$ events collected with the BESIII detector operating at the BEPCII storage ring. Events of the reaction channels $h_{c} \\rightarrow \\gamma \\eta'$ and $\\gamma \\eta$ are observed with a statistical significance of $8.4 \\sigma$ and $4.0 \\sigma$, respectively, for the first time. The branching fractions of $h_{c} \\rightarrow \\gamma \\eta'$ and $h_{c} \\rightarrow \\gamma \\eta$ are measured to be $\\mathcal{B}(h_{c} \\rightarrow \\gamma \\eta')=(1.52 \\pm 0.27 \\pm 0.29)\\times10^{-3}$ and $\\mathcal{B}(h_{c} \\rightarrow \\gamma \\eta)=(4.7 \\pm 1.5 \\pm 1.4)\\times10^{-4}$, respectively, where the first errors are statistical and the second are systematic uncertainties.

  16. Constraints on emissions of carbon monoxide, methane, and a suite of hydrocarbons in the Colorado Front Range using observations of 14CO2

    Directory of Open Access Journals (Sweden)

    P. P. Tans

    2013-01-01

    Full Text Available Atmospheric radiocarbon (14CO represents an important observational constraint on emissions of fossil-fuel derived carbon into the atmosphere due to the absence of 14CO in fossil fuel reservoirs. The high sensitivity and precision that accelerator mass spectrometry (AMS affords in atmospheric 14CO analysis has greatly increased the potential for using such measurements to evaluate bottom-up emissions inventories of fossil fuel CO2 (CO2ff, as well as those for other co-emitted species. Here we use observations of 14CO2 and a series of hydrocarbons and combustion tracers from discrete air samples collected between June 2009 and September 2010 at the National Oceanic and Atmospheric Administration Boulder Atmospheric Observatory (BAO; Lat: 40.050° N, Lon: 105.004° W to derive emission ratios of each species to CO2ff. From these emission ratios, we estimate emissions of these species by using the Vulcan CO2ff high resolution data product as a reference. The species considered in this analysis are carbon monoxide (CO, methane (CH4, acetylene (C2H2, benzene (C6H6, and C3–C5 alkanes. Comparisons of top-down emissions estimates are made to existing inventories of these species for Denver and adjacent counties, as well as to previous efforts to estimate emissions from atmospheric observations over the same area. We find that CO is overestimated in the 2008 National Emissions Inventory (NEI, 2008 by a factor of ~2. A close evaluation of the inventory suggests that the ratio of CO emitted per unit fuel burned from on-road gasoline vehicles is likely over-estimated by a factor of 2.5. The results also suggest that while the oil and gas sector is the largest contributor to the CH4 signal in air arriving from the north and east, it is very likely that other sources, including agricultural sources, contribute to this signal and must be accounted for when attributing these signals to oil and gas industry activity from a top-down perspective. Our results are

  17. Identification of emission sources of particle-bound polycyclic aromatic hydrocarbons in the vicinity of the industrial zone of the city of Novi Sad

    Directory of Open Access Journals (Sweden)

    Jovčić Nataša S.

    2013-01-01

    Full Text Available Data on polycyclic aromatic hydrocarbons (PAHs in ambient air accessed at selected locations in the vicinity of the industrial zone of the city of Novi Sad, Serbia, have been presented and analyzed in order to determine seasonal and spatial variations and to identify emission sources of particle-bound PAHs. Previous studies have demonstrated that the major contributors of PAHs in urban areas are the emissions from vehicle exhaust, and emissions releases from industrial processes like aluminium production, creosote and wood preservation, waste incineration, cement manufacture, petrochemical and related industries, commercial heat/power production etc. The sampling campaigns have been conducted at three sampling sites, during the two 14-day periods. The first site was situated near industrial area, with a refinery, power plant and heavy-traffic road in the vicinity. The second site was located nearby the heavy traffic area, especially busy during the rush hour. The third site was residential district. Summer sampling period lasted from June 26th to July 10th 2008, while sampling of ambient air during the winter was undertaken from January 22nd to February 5th 2009. Eighty-four (84 air samples were collected using a high volume air sampler TCR Tecora H0649010/ECHO. 16 US EPA polycyclic aromatic hydrocarbons were determined in all samples using a gas chromatographer with a mass spectrometer as a detector (Shimatzu MDGC/GCMS-2010. The total average concentrations of PAHs ranged from 1.21 to 1.77 ng/m3 during the summer period and from 6.31 to 7.25 ng/m3 in the winter. Various techniques, including diagnostic ratio (DR and principal component analysis (PCA, have been used to define and evaluate potential emission sources of PAHs. Diagnostic ratio analysis indicated that vehicles, diesel or/and gasoline, industrial and combustion emissions were sources of PAHs in the vicinity of the industrial zone. Additionally, principal component analysis was used

  18. [An investigation of the formation of] polycyclic aromatic hydrocarbon (PAH) emissions when firing pulverized coal in a bench-scale drop tube reactor

    Energy Technology Data Exchange (ETDEWEB)

    Pisupati, S.V.; Wasco, R.S.; Scaroni, A.W. [Pennsylvania State Univ., University Park, PA (United States). Combustion Lab.

    1998-12-31

    The Clean Air Act Amendments (CAAA) of 1990 contain provisions which will set standards for the allowable emissions of 188 analytes designated as hazardous air pollutants (HAPs). This list of HAPs was used to establish an initial list of source categories for which EPA would be required to establish technology-based emission standards, which would result in regulated sources sharply reducing routine emissions of toxic air pollutants. Polycyclic organic matter (POM) has also been referred to as polynuclear or polycyclic aromatic compounds (PACs). Nine major categories of POM have been defined by EPA. The study of organic compounds from coal combustion is complex and the results obtained so far are inconclusive with respect to emission factors. The most common organic compounds in the flue gas of coal-fired power plants are polycyclic aromatic hydrocarbons (PAHs). Furthermore, EPA has specified 16 PAH compounds as priority pollutants. These are naphthalene, acenaphthylene, acenaphthene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene, chrysene, benz[a]anthracene, benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, indeno[1,2,3-cd]pyrene, benzo[ghi]perylene, and dibenz[ah]anthracene. Penn State`s Combustion Laboratory is equipped to collect and analyze the HAPs in the flue gas from fossil fuels combustion. The overall objective of this study was to examine the effect of unit temperature on PAH emissions. A Modified Method 5 sampling train was used to isokinetically collect samples at desired locations in flue gas streams. The collected sample can be separated into solid, condensed liquid and gaseous phases. The PAHs of interest are extracted from the collected sample, concentrated, then separated and quantified by gas chromatography/mass spectrometry (GC/MS). This study was conducted using a bench-scale drop-tube reactor (DTR). The fuel selected for this study was a Middle Kittanning seam coal pulverized to 80% passing US Standard 200 mesh (commonly

  19. Impact of using fishing boat fuel with high poly aromatic content on the emission of polycyclic aromatic hydrocarbons from the diesel engine

    Science.gov (United States)

    Lin, Yuan-Chung; Lee, Wen-Jhy; Li, Hsing-Wang; Chen, Chung-Ban; Fang, Guor-Cheng; Tsai, Perng-Jy

    Because of the fishery subsidy policy, the fishing boat fuel oil (FBFO) exemption from commodity taxes, business taxes and air pollution control fees, resulted in the price of FBFO was ˜50% lower than premium diesel fuel (PDF) in Taiwan. It is estimated that ˜650,000 kL FBFO was illegally used by traveling diesel-vehicles (TDVs) with a heavy-duty diesel engine (HDDE), which accounted for ˜16.3% of the total diesel fuel consumed by TDVs. In this study, sulfur, poly aromatic and total-aromatic contents in both FBFO and PDF were measured and compared. Exhaust emissions of polycyclic aromatic hydrocarbons (PAHs) and their carcinogenic potencies (BaP eq) from a HDDE under transient cycle testing for both FBFO and PDF were compared and discussed. Finally, the impact caused by the illegal use of FBFO on the air quality was examined. Results show that the mean sulfur-, poly aromatic and aromatic-contents in FBFO were 43.0, 3.89 and 1.04 times higher than that of PDF, respectively. Emission factors of total-PAHs and total-BaP eq obtained by utilizing FBFO were 51.5 and 0.235 mg L -1-Fuel, which were 3.41 and 5.82 times in magnitude higher than obtained by PDF, respectively. The estimated annual emissions of total-PAHs and total-BaP eq to the ambient environment due to the illegally used FBFO were 23.6 and 0.126 metric tons, respectively, which resulted in a 17.9% and a 25.0% increment of annual emissions from all mobile sources, respectively. These results indicated that the FBFO used illegally by TDVs had a significant impact on PAH emissions to the ambient environment.

  20. A Survey of HC3N in Extragalactic Sources - Is HC3N a Tracer of Activity in ULIRGs?

    DEFF Research Database (Denmark)

    Lindberg, Karl Johan Erik; Aalto, S.; Costagliola, F.;

    2011-01-01

    Context. HC3N is a molecule that is mainly associated with Galactic star-forming regions, but it has also been detected in extragalactic environments. Aims. To present the first extragalactic survey of HC3N, when combining earlier data from the literature with six new single-dish detections, and ...

  1. A Survey of HC3N in Extragalactic Sources - Is HC3N a Tracer of Activity in ULIRGs?

    CERN Document Server

    Lindberg, J E; Costagliola, F; Pérez-Beaupuits, J -P; Monje, R; Muller, S

    2011-01-01

    Context. HC3N is a molecule that is mainly associated with Galactic star-forming regions, but it has also been detected in extragalactic environments. Aims. To present the first extragalactic survey of HC3N, when combining earlier data from the literature with six new single-dish detections, and to compare HC3N with other molecular tracers (HCN, HNC), as well as other properties (silicate absorption strength, IR flux density ratios, C II flux, and megamaser activity). Methods. We present mm IRAM 30 m, OSO 20 m, and SEST observations of HC3N rotational lines (mainly the J = 10-9 transition) and of the J = 1-0 transitions of HCN and HNC. Our combined HC3N data account for 13 galaxies (excluding the upper limits reported for the non-detections), while we have HCN and HNC data for more than 20 galaxies. Results. A preliminary definition "HC3N-luminous galaxy" is made based upon the HC3N/HCN ratio. Most (~80 %) HC3N-luminous galaxies seem to be deeply obscured galaxies and (U)LIRGs. A majority (~60 % or more) of t...

  2. A survey of HC3N in extragalactic sources Is HC3N a tracer of activity in ULIRGs?

    NARCIS (Netherlands)

    Lindberg, J. E.; Aalto, S.; Costagliola, F.; Perez-Beaupuits, J. -P.; Monje, R.; Muller, S.

    2011-01-01

    Context. HC3N is a molecule that is mainly associated with Galactic star-forming regions, but it has also been detected in extragalactic environments. Aims. To present the first extragalactic survey of HC3N, when combining earlier data from the literature with six new single-dish detections, and to

  3. A Survey of HC3N in Extragalactic Sources - Is HC3N a Tracer of Activity in ULIRGs?

    DEFF Research Database (Denmark)

    Lindberg, Karl Johan Erik; Aalto, S.; Costagliola, F.;

    2011-01-01

    Context. HC3N is a molecule that is mainly associated with Galactic star-forming regions, but it has also been detected in extragalactic environments. Aims. To present the first extragalactic survey of HC3N, when combining earlier data from the literature with six new single-dish detections......) and of the J = 1-0 transitions of HCN and HNC. Our combined HC3N data account for 13 galaxies (excluding the upper limits reported for the non-detections), while we have HCN and HNC data for more than 20 galaxies. Results. A preliminary definition "HC3N-luminous galaxy" is made based upon the HC3N/HCN ratio....... Most (~80 %) HC3N-luminous galaxies seem to be deeply obscured galaxies and (U)LIRGs. A majority (~60 % or more) of the HC3N-luminous galaxies in the sample present OH mega- or strong kilomaser activity. A possible explanation is that both HC3N and OH megamasers need warm dust for their excitation...

  4. ALMA MEASUREMENTS OF THE HNC AND HC{sub 3}N DISTRIBUTIONS IN TITAN'S ATMOSPHERE

    Energy Technology Data Exchange (ETDEWEB)

    Cordiner, M. A.; Nixon, C. A.; Serigano, J.; Charnley, S. B.; Milam, S. N.; Mumma, M. J.; Villanueva, G.; Paganini, L. [NASA Goddard Space Flight Center, 8800 Greenbelt Road, Greenbelt, MD 20771 (United States); Teanby, N. A. [School of Earth Sciences, University of Bristol, Wills Memorial Building, Queen' s Road, Bristol BS8 1RJ (United Kingdom); Irwin, P. G. J. [Atmospheric, Oceanic, and Planetary Physics, Clarendon Laboratory, University of Oxford, Parks Road, Oxford OX1 3PU (United Kingdom); Lis, D. C. [Sorbonne Universités, Université Pierre et Marie Curie, Paris 6, CNRS, Observatoire de Paris, UMR 8112, LERMA, F-75014 Paris (France); Kuan, Y.-J. [National Taiwan Normal University, Taipei 116, Taiwan, ROC (China); Remijan, A. J., E-mail: martin.cordiner@nasa.gov [National Radio Astronomy Observatory, Charlottesville, VA 22903 (United States)

    2014-11-10

    We present spectrally and spatially resolved maps of HNC and HC{sub 3}N emission from Titan's atmosphere, obtained using the Atacama Large Millimeter/submillimeter Array on 2013 November 17. These maps show anisotropic spatial distributions for both molecules, with resolved emission peaks in Titan's northern and southern hemispheres. The HC{sub 3}N maps indicate enhanced concentrations of this molecule over the poles, consistent with previous studies of Titan's photochemistry and atmospheric circulation. Differences between the spectrally integrated flux distributions of HNC and HC{sub 3}N show that these species are not co-spatial. The observed spectral line shapes are consistent with HNC being concentrated predominantly in the mesosphere and above (at altitudes z ≳ 400 km), whereas HC{sub 3}N is abundant at a broader range of altitudes (z ≈ 70-600 km). From spatial variations in the HC{sub 3}N line profile, the locations of the HC{sub 3}N emission peaks are shown to be variable as a function of altitude. The peaks in the integrated emission from HNC and the line core (upper atmosphere) component of HC{sub 3}N (at z ≳ 300 km) are found to be asymmetric with respect to Titan's polar axis, indicating that the mesosphere may be more longitudinally variable than previously thought. The spatially integrated HNC and HC{sub 3}N spectra are modeled using the NEMESIS planetary atmosphere code and the resulting best-fitting disk-averaged vertical mixing ratio profiles are found to be in reasonable agreement with previous measurements for these species. Vertical column densities of the best-fitting gradient models for HNC and HC{sub 3}N are 1.9 × 10{sup 13} cm{sup –2} and 2.3 × 10{sup 14} cm{sup –2}, respectively.

  5. Combination of photocatalysis and HC/SCR for improved activity and durability of DeNOx catalysts.

    Science.gov (United States)

    Heo, Iljeong; Kim, Mun Kyu; Sung, Samkyung; Nam, In-Sik; Cho, Byong K; Olson, Keith L; Li, Wei

    2013-04-16

    A photocatalytic HC/SCR system has been developed and its high deNOx performance (54.0-98.6% NOx conversion) at low temperatures (150-250 °C) demonstrated by using a representative diesel fuel hydrocarbon (dodecane) as the reductant over a hybrid SCR system of a photocatalytic reactor (PCR) and a dual-bed HC/SCR reactor. The PCR generates highly active oxidants such as O3 and NO2 from O2 and NO in the feed stream, followed by the subsequent formation of highly efficient reductants such as oxygenated hydrocarbon (OHC), NH3, and organo-nitrogen compounds. These reductants are the key components for enhancing the low temperature deNOx performance of the dual-bed HC/SCR system containing Ag/Al2O3 and CuCoY in the front and rear bed of the reactor, respectively. The OHCs are particularly effective for both NOx reduction and NH3 formation over the Ag/Al2O3 catalyst, while NH3 and organo-nitrogen compounds are effective for NOx reduction over the CuCoY catalyst. The hybrid HC/SCR system assisted by photocatalysis has shown an overall deNOx performance comparable to that of the NH3/SCR, demonstrating its potential as a promising alternative to the current urea/SCR and LNT technologies. Superior durability of HC/SCR catalysts against coking by HCs has also been demonstrated by a PCR-assisted regeneration scheme for deactivating catalysts.

  6. Polycyclic Aromatic Hydrocarbon Emission in Spitzer/IRS Maps. II. A Direct Link between Band Profiles and the Radiation Field Strength

    Science.gov (United States)

    Stock, D. J.; Peeters, E.

    2017-03-01

    We decompose the observed 7.7 μm polycyclic aromatic hydrocarbon (PAH) emission complexes in a large sample of over 7000 mid-infrared spectra of the interstellar medium using spectral cubes observed with the Spitzer/IRS-SL instrument. In order to fit the 7.7 μm PAH emission complex we invoke four Gaussian components, which are found to be very stable in terms of their peak positions and widths across all of our spectra, and subsequently define a decomposition with fixed parameters, which gives an acceptable fit for all the spectra. We see a strong environmental dependence on the interrelationships between our band fluxes—in the H ii regions all four components are intercorrelated, while in the reflection nebulae (RNs) the inner and outer pairs of bands correlate in the same manner as previously seen for NGC 2023. We show that this effect arises because the maps of RNs are dominated by emission from strongly irradiated photodissociation regions, while the much larger maps of H ii regions are dominated by emission from regions much more distant from the exciting stars, leading to subtly different spectral behavior. Further investigation of this dichotomy reveals that the ratio of two of these components (centered at 7.6 and 7.8 μm) is linearly related to the UV-field intensity (log G 0). We find that this relationship does not hold for sources consisting of circumstellar material, which are known to have variable 7.7 μm spectral profiles.

  7. Field measurement of emission factors of PM, EC, OC, parent, nitro-, and oxy- polycyclic aromatic hydrocarbons for residential briquette, coal cake, and wood in rural Shanxi, China.

    Science.gov (United States)

    Shen, Guofeng; Tao, Shu; Wei, Siye; Chen, Yuanchen; Zhang, Yanyan; Shen, Huizhong; Huang, Ye; Zhu, Dan; Yuan, Chenyi; Wang, Haochen; Wang, Yafei; Pei, Lijun; Liao, Yilan; Duan, Yonghong; Wang, Bin; Wang, Rong; Lv, Yan; Li, Wei; Wang, Xilong; Zheng, Xiaoying

    2013-03-19

    Air pollutants from residential solid fuel combustion are attracting growing public concern. Field measured emission factors (EFs) of various air pollutants for solid fuels are close to the reality and urgently needed for better emission estimations. In this study, emission factors of particulate matter (PM), organic carbon (OC), elemental carbon (EC), and various polycyclic aromatic hydrocarbons (PAHs) from residential combustions of coal briquette, coal cake, and wood were measured in rural Heshun County, China. The measured EFs of PM, OC, and EC were 8.1-8.5, 2.2-3.6, 0.91-1.6 g/kg for the wood burnt in a simple metal stove, 0.54-0.64, 0.13-0.14, 0.040-0.0041 g/kg for the briquette burned in an improved stove with a chimney, and 3.2-8.5, 0.38-0.58, 0.022-0.052 g/kg for the homemade coal cake combusted in a brick stove with a flue, respectively. EFs of 28 parent PAHs, 4 oxygenated PAHs, and 9 nitro-PAHs were 182-297, 7.8-10, 0.14-0.55 mg/kg for the wood, 14-16, 1.7-2.6, 0.64-0.83 mg/kg for the briquette, and 168-223, 4.7-9.5, 0.16-2.4 mg/kg for the coal cake, respectively. Emissions from the wood and coal cake combustions were much higher than those for the coal briquette, especially true for high molecular weight PAHs. Most EFs measured in the field were higher than those measured in stove combustions under laboratory conditions.

  8. The effects of deterioration and technological levels on pollutant emission factors for gasoline light-duty trucks.

    Science.gov (United States)

    Zhang, Qingyu; Fan, Juwang; Yang, Weidong; Chen, Bixin; Zhang, Lijuan; Liu, Jiaoyu; Wang, Jingling; Zhou, Chunyao; Chen, Xuan

    2017-07-01

    Vehicle deterioration and technological change influence emission factors (EFs). In this study, the impacts of vehicle deterioration and emission standards on EFs of regulated pollutants (carbon monoxide [CO], hydrocarbon [HC], and nitrogen oxides [NOx]) for gasoline light-duty trucks (LDTs) were investigated according to the inspection and maintenance (I/M) data using a chassis dynamometer method. Pollutant EFs for LDTs markedly varied with accumulated mileages and emission standards, and the trends of EFs are associated with accumulated mileages. In addition, the study also found that in most cases, the median EFs of CO, HC, and NOx are higher than those of basic EFs in the International Vehicle Emissions (IVE) model; therefore, the present study provides correction factors for the IVE model relative to the corresponding emission standards and mileages. Currently, vehicle emissions are great contributors to air pollution in cities, especially in developing countries. Emission factors play a key role in creating emission inventory and estimating emissions. Deterioration represented by vehicle age and accumulated mileage and changes of emission standards markedly influence emission factors. In addition, the results provide collection factors for implication in the IVE model in the region levels.

  9. High Resolution HC3N Observations toward the Central Region of Sagittarius B2

    Science.gov (United States)

    Chung, Hyun Soo; Ohishi, Masatoshi; Morimoto, Masaki

    1994-04-01

    We have observed the emission of HC3N J=4-3, 5-4, 10-9 and 12-11 transitions toward the Sgr B2 central region in an area of 150"*150" with resolution of 16"-48". The intensities and central velocities of line profiles show significant variations with positions. In contrast to the intensities of the low J-level transitions which gradually increase from the central source toward the outside region, the HC3N emission of the high J-level transition become stronger toward the central radio continuum source MD5. Systematic change in the radial velocity of each line profile occurs along north-south direction. There are a few peaks in most line profiles, and these indicate that there are multiple velocity components along the line of sight. Distributions of excitation temperature and column density which were estimated from the excitation calculations show the existence of a small(1*2pc), hot(Tex > 50K) core which contains two temperature peaks at about 15" east and north of MD5. The column density of HC3N is (1-3)*10E14 /cm2. Column density at distant position from MD5 is larger than that in the central region. We have deduced that this 'hot-core' has a mass of 10E5 Mo, which is about an order of magnitude larger than those obtained by previous studies.

  10. A Chemical Kinetic Modeling Study of the Effects of Oxygenated Hydrocarbons on Soot Emissions from Diesel Engines

    Energy Technology Data Exchange (ETDEWEB)

    Westbrook, C K; Pitz, W J; Curran, H J

    2005-11-14

    A detailed chemical kinetic modeling approach is used to examine the phenomenon of suppression of sooting in diesel engines by addition of oxygenated hydrocarbon species to the fuel. This suppression, which has been observed experimentally for a few years, is explained kinetically as a reduction in concentrations of soot precursors present in the hot products of a fuel-rich diesel ignition zone when oxygenates are included. Oxygenates decrease the overall equivalence ratio of the igniting mixture, producing higher ignition temperatures and more radical species to consume more soot precursor species, leading to lower soot production. The kinetic model is also used to show how different oxygenates, ester structures in particular, can have different soot-suppression efficiencies due to differences in molecular structure of the oxygenated species.

  11. A Chemical Kinetic Modeling Study of the Effects of Oxygenated Hydrocarbons on Soot Emissions from Diesel Engines

    Energy Technology Data Exchange (ETDEWEB)

    Westbrook, C K; Pitz, W J; Curran, H J

    2005-11-14

    A detailed chemical kinetic modeling approach is used to examine the phenomenon of suppression of sooting in diesel engines by addition of oxygenated hydrocarbon species to the fuel. This suppression, which has been observed experimentally for a few years, is explained kinetically as a reduction in concentrations of soot precursors present in the hot products of a fuel-rich diesel ignition zone when oxygenates are included. Oxygenates decrease the overall equivalence ratio of the igniting mixture, producing higher ignition temperatures and more radical species to consume more soot precursor species, leading to lower soot production. The kinetic model is also used to show how different oxygenates, ester structures in particular, can have different soot-suppression efficiencies due to differences in molecular structure of the oxygenated species.

  12. Environmental dependence of polycyclic aromatic hydrocarbon emission at z~0.8. Investigation by observing the RX J0152.7-1357 with AKARI

    CERN Document Server

    Murata, Kazumi; Tanaka, Masayuki; Matsuhara, Hideo; Kodama, Tadayuki

    2015-01-01

    We study the environmental dependence of the strength of polycyclic aromatic hydrocarbon (PAH) emission by AKARI observations of RX J0152.7-1357, a galaxy cluster at z=0.84. PAH emission reflects the physical conditions of galaxies and dominates 8 um luminosity (L8), which can directly be measured with the L15 band of AKARI. L8 to infrared luminosity (LIR) ratio is used as a tracer of the PAH strength. Both photometric and spectroscopic redshifts are applied to identify the cluster members. The L15-band-detected galaxies tend to reside in the outskirt of the cluster and have optically green colour, R-z'~ 1.2. We find no clear difference of the L8/LIR behaviour of galaxies in field and cluster environment. The L8/LIR of cluster galaxies decreases with specific-star-formation rate divided by that of main-sequence galaxies, and with LIR, consistent with the results for field galaxies. The relation between L8/LIR and LIR is between those at z=0 and z=2 in the literature. Our data also shows that starburst galaxie...

  13. Simultaneous NOx and hydrocarbon emissions control for lean-burn engines using low-temperature solid oxide fuel cell at open circuit.

    Science.gov (United States)

    Huang, Ta-Jen; Hsu, Sheng-Hsiang; Wu, Chung-Ying

    2012-02-21

    The high fuel efficiency of lean-burn engines is associated with high temperature and excess oxygen during combustion and thus is associated with high-concentration NO(x) emission. This work reveals that very high concentration of NO(x) in the exhaust can be reduced and hydrocarbons (HCs) can be simultaneously oxidized using a low-temperature solid oxide fuel cell (SOFC). An SOFC unit is constructed with Ni-YSZ as the anode, YSZ as the electrolyte, and La(0.6)Sr(0.4)CoO(3) (LSC)-Ce(0.9)Gd(0.1)O(1.95) as the cathode, with or without adding vanadium to LSC. SOFC operation at 450 °C and open circuit can effectively treat NO(x) over the cathode at a very high concentration in the simulated exhaust. Higher NO(x) concentration up to 5000 ppm can result in a larger NO(x) to N(2) rate. Moreover, a higher oxygen concentration promotes NO conversion. Complete oxidation of HCs can be achieved by adding silver to the LSC current collecting layer. The SOFC-based emissions control system can treat NO(x) and HCs simultaneously, and can be operated without consuming the anode fuel (a reductant) at near the engine exhaust temperature to eliminate the need for reductant refilling and extra heating.

  14. Emission of polycyclic aromatic hydrocarbons, toxicity, and mutagenicity from domestic cooking using sawdust briquettes, wood, and kerosene.

    Science.gov (United States)

    Kim, OanhNguyenThi; Nghiem, Le Hoang; Phyu, Yin Latt

    2002-03-01

    Smoke samples, in both gas and particulate matter (PM) phases, of the three domestic stoves were collected using U.S. EPA modified method 5 and were analyzed for 17 PAH (HPLC-UV), acute toxicity (Microtox test), and mutagenicity (Amestest). The gas phase of smoke contributed > or = 95% of 17 PAH, > or = 96% of toxicity, and > or = 60% of mutagenicity. The highest emission factor of 17 PAH was from sawdust briquettes (260 mg/kg), but the highest emission of 11 genotoxic PAH was from kerosene (28 mg/kg). PM samples of kerosene smoke were not toxic. The total toxicity emission factor was the highest from sawdust, followed by kerosene and wood fuel. Smoke samples from the kerosene stove were not mutagenic. TA98 indicated the presence of both direct and indirect mutagenic activities in PM samples of sawdust and wood fuel but only direct mutagenic activities in the gas phase. TA100 detected only direct mutagenic activities in both PM and gas-phase samples. The higher mutagenicity emission factor was from wood fuel, 12 x 10(6) revertants/kg (TA100-S9) and 3.5 x 10(6) (TA98-S9), and lower from sawdust, 2.9 x 10(6) (TA100-S9) and 2.8 x 10(6) (TA98-S9). The low burning rate and high efficiency of a kerosene stove have resulted in the lowest PAH, toxicity, and mutagenicity emissions from daily cooking activities. The bioassays produced toxicity and mutagenicity results in correspondence with the PAH content of samples. The tests could be used for a quick assessment of potential health risks.

  15. Improved Gas Filling and Sealing of an HC-PCF

    Science.gov (United States)

    Poberezhskiy, Ilya; Meras, Patrick; Chang, Daniel; Spiers, Gary

    2008-01-01

    An improved packaging approach has been devised for filling a hollow-core photonic-crystal fiber (HC-PCF) with a gas, sealing the HC-PCF to retain the gas, and providing for optical connections and, optionally, a plumbing fitting for changing or augmenting the gas filling. Gas-filled HC-PCFs can be many meters long and have been found to be attractive as relatively compact, lightweight, rugged alternatives to conventional gas-filled glass cells for use as molecular-resonance frequency references for stabilization of lasers in some optical-metrology, lidar, optical-communication, and other advanced applications. Prior approaches to gas filling and sealing of HC-PCFs have involved, variously, omission of any attempt to connectorize the PCF, connectorization inside a vacuum chamber (an awkward and expensive process), or temporary exposure of one end of an HC-PCF to the atmosphere, potentially resulting in contamination of the gas filling. Prior approaches have also involved, variously, fusion splicing of HC-PCFs with other optical fibers or other termination techniques that give rise to Fresnel reflections of about 4 percent, which results in output intensity noise.

  16. Attributing risk burden of PM2.5-bound polycyclic aromatic hydrocarbons to major emission sources: Case study in Guangzhou, south China

    Science.gov (United States)

    Yu, Qingqing; Gao, Bo; Li, Guanghui; Zhang, Yanli; He, Quanfu; Deng, Wei; Huang, Zhonghui; Ding, Xiang; Hu, Qihou; Huang, Zuzhao; Wang, Yujun; Bi, Xinhui; Wang, Xinming

    2016-10-01

    Polycyclic aromatic hydrocarbons (PAHs) have attracted an increasing concern in China's megacities. However, rare information is available on the spatial and seasonal variations of inhalation cancer risk (ICR) due to PAH exposure and their relations to specific sources. In this study, year-round PM2.5 samples were collected from 2013 to 2014 by high-volume samplers at four sites (one urban, two rural and one roadside station) in Guangzhou in the highly industrialized and densely populated Pearl River Delta (PRD) region and analyzed for 26 polycyclic aromatic hydrocarbons (PAHs) together with molecular tracers including levoglucosan, hopanes and elemental carbon. Higher molecular weight PAHs (5-ring or above) accounted for 64.3-87.5% of total PAHs. Estimated annual averages of benzo(a)pyrene-equivalent carcinogenic potency (BaPeq) were 1.37, 2.31 and 1.56 ng/m3 at urban SZ, rural JL and rural WQS, respectively, much higher than that at the roadside station YJ in an urban street canyon. ICR of PAHs in wintertime reached 2.2 × 10-4, nearly 3 times that in summer; and cancer risk of PAHs was surprisingly higher at the rural site than at other sites. Source contributions by positive matrix factorization (PMF) in the aid of molecular tracers revealed that overall coal combustion and biomass burning altogether contributed 73.8% of total PAHs and 85.2% of BaPeq, and particularly in winter biomass burning became the most significant source of total PAHs and BaPeq (51.8% and 52.5%), followed by coal combustion (32.0% and 39.1%) and vehicle emission (16.2% and 8.4%). The findings of this work suggest that even in China's megacities like Guangzhou, limiting biomass burning may benefit PAHs pollution control and cancer risk reduction.

  17. On-road traffic emissions of polycyclic aromatic hydrocarbons and their oxy- and nitro- derivative compounds measured in road tunnel environments.

    Science.gov (United States)

    Keyte, Ian J; Albinet, Alexandre; Harrison, Roy M

    2016-10-01

    Vehicular emissions are a key source of polycyclic aromatic compounds (PACs), including polycyclic aromatic hydrocarbons (PAHs) and their oxygenated (OPAH) and nitrated (NPAH) derivatives, in the urban environment. Road tunnels are a useful environment for the characterisation of on-road vehicular emissions, providing a realistic traffic fleet and a lack of direct sunlight, chemical reactivity and non-traffic sources. In the present investigation the concentrations of selected PAHs, OPAHs and NPAHs have been measured in the Parc des Princes Tunnel in Paris (PdPT, France), and at the Queensway Road Tunnel and an urban background site in Birmingham (QT, U.K). A higher proportion of semi-volatile (3-4 ring) PAH, OPAH and NPAH compounds are associated with the particulate phase compared with samples from the ambient environment. A large (~85%) decline in total PAH concentrations is observed between 1992 and 2012 measurements in QT. This is attributed primarily to the introduction of catalytic converters in the U.K as well as increasingly stringent EU vehicle emissions legislation. In contrast, NPAH concentrations measured in 2012 are similar to those measured in 1996. This observation, in addition to an increased proportion of (Phe+Flt+Pyr) in the observed PAH burden in the tunnel, is attributed to the increased number of diesel passenger vehicles in the U.K during this period. Except for OPAHs, comparable PAH and NPAH concentrations are observed in both investigated tunnels (QT and PdP). Significant differences are shown for specific substances between PAC chemical profiles in relation with the national traffic fleet differences (33% diesel passenger cars in U.K. vs 69% in France and up to 80% taking into account all vehicle categories). The dominating and sole contribution of 1-Nitropyrene observed in the PdPT NPAH profile strengthens the promising use of this compound as a diesel exhaust marker for PM source apportionment studies.

  18. VizieR Online Data Catalog: SOLIS. II. OMC2-FIR4 HC3N and HC5N images (

    Science.gov (United States)

    Fontani, F.; Ceccarelli, C.; Favre, C.; Caselli, P.; Neri, R.; Sims, I. R.; Kahane, C.; Alves, F.; Balucani, N.; Bianchi, E.; Caux, E.; Jaber Al-Edhari, A.; Lopez-Sepulcre, A.; Pineda, J.; Bachiller, R.; Bizzocchi, L.; Bottinelli, S.; Chacon-Tanarro, A.; Choudhury, R.; Codella, C.; Coutens, A.; Dulieu, F.; Feng, S.; Rimola, A.; Hily-Blant, P.; Holdship, J.; Jimenez-Serra, I.; Laas, J.; Lefloch, B.; Oya, Y.; Podio, L.; Pon, A.; Punanova, A.; Quenard, D.; Sakai, N.; Spezzano, S.; Taquet, V.; Testi, L.; Theule, P.; Ugliengo, P.; Vastel, C.

    2017-08-01

    IRAM-NOEMA Interferometer, 3mm receiver, Widex and Narrow-band correlators. Observations with the IRAM NOEMA Interferometer of HC3N (9-8) and HC5N (31-30), at rest frequencies 81.881468GHz and 82.539039GHz , respectively, towards OMC-2 FIR4 have been carried out over 5 days between the 5th and the 19th of August, 2015. The HC3N line was observed in the Widex band correlator, providing a resolution in velocity of ~7.15km/s, while the HC5N line was observed also in the Narrow band correlator with a resolution in velocity of ~0.57km/s. (2 data files).

  19. Hotspot of glyoxal over the Pearl River delta seen from the OMI satellite instrument: implications for emissions of aromatic hydrocarbons

    Science.gov (United States)

    Miller, Christopher Chan; Jacob, Daniel J.; González Abad, Gonzalo; Chance, Kelly

    2016-04-01

    The Pearl River delta (PRD) is a densely populated hub of industrial activity located in southern China. OMI (Ozone Monitoring Instrument) satellite observations reveal a large hotspot of glyoxal (CHOCHO) over the PRD that is almost twice as large as any other in Asia. Formaldehyde (HCHO) and NO2 observed by OMI are also high in the PRD but no more than in other urban/industrial areas of China. The CHOCHO hotspot over the PRD can be explained by industrial paint and solvent emissions of aromatic volatile organic compounds (VOCs), with toluene being a dominant contributor. By contrast, HCHO in the PRD originates mostly from VOCs emitted by combustion (principally vehicles). By applying a plume transport model to wind-segregated OMI data, we show that the CHOCHO and HCHO enhancements over the PRD observed by OMI are consistent with current VOC emission inventories. Prior work using CHOCHO retrievals from the SCIAMACHY satellite instrument suggested that emission inventories for aromatic VOCs in the PRD were too low by a factor of 10-20; we attribute this result in part to bias in the SCIAMACHY data and in part to underestimated CHOCHO yields from oxidation of aromatics. Our work points to the importance of better understanding CHOCHO yields from the oxidation of aromatics in order to interpret space-based CHOCHO observations in polluted environments.

  20. Comparison of the fuel oil biodegradation potential of hydrocarbon-assimilating microorganisms isolated from a temperate agricultural soil

    Energy Technology Data Exchange (ETDEWEB)

    Chaineau, C.H.; Dupont, J.; Bury, E.; Oudot, J. [Museum National d' Histoire Naturelle, Laboratoire de Cryptogamie, 12 rue Buffon, 75005 Paris (France); Morel, J. [Ecole Nationale Superieure d' Agronomie et des Industries Alimentaires de Nancy, Laboratoire Sols et Environnement, INRA, 2 avenue de la Foret de Haye, B.P. 172, F-54505 Vandoeuvre-les-Nancy (France)

    1999-03-09

    Strains of hydrocarbon-degrading microorganisms (bacteria and fungi) were isolated from an agricultural soil in France. In a field, a portion was treated with oily cuttings resulting from the drilling of an onshore well. The cuttings which were spread at the rate of 600 g HC m{sup -2} contained 10% of fuel oil hydrocarbons (HC). Another part of the field was left untreated. Three months after HC spreading, HC adapted bacteria and fungi were isolated at different soil depths in the two plots and identified. The biodegradation potential of the isolated strains was monitored by measuring the degradation rate of total HC, saturated hydrocarbons, aromatic hydrocarbons and resins of the fuel. Bacteria of the genera Pseudomonas, Brevundimonas, Sphingomonas, Acinetobacter, Rhodococcus, Arthrobacter, Corynebacterium and fungi belonging to Aspergillus, Penicillium, Beauveria, Acremonium, Cladosporium, Fusarium, and Trichoderma were identified. The most active strains in the assimilation of saturates and aromatics were Arthrobacter sp., Sphingomonas spiritivorum, Acinetobacter baumanii, Beauveria alba and Penicillum simplicissimum. The biodegradation potential of the hydrocarbon utilizing microorganisms isolated from polluted or unpolluted soils were similar. In laboratory pure cultures, saturated HC were more degraded than aromatic HC, whereas resins were resistant to microbial attack. On an average, individual bacterial strains were more active than fungi in HC biodegradation. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

  1. Comparison of the fuel oil biodegradation potential of hydrocarbon-assimilating microorganisms isolated from a temperate agricultural soil

    Energy Technology Data Exchange (ETDEWEB)

    Chaineau, C.H.; Dupont, J.; Bury, E.; Oudot, J. [Museum National d`Histoire Naturelle, Laboratoire de Cryptogamie, 12 rue Buffon, 75005 Paris (France); Morel, J. [Ecole Nationale Superieure d`Agronomie et des Industries Alimentaires de Nancy, Laboratoire Sols et Environnement, INRA, 2 avenue de la Foret de Haye, B.P. 172, F-54505 Vandoeuvre-les-Nancy (France)

    1999-03-09

    Strains of hydrocarbon-degrading microorganisms (bacteria and fungi) were isolated from an agricultural soil in France. In a field, a portion was treated with oily cuttings resulting from the drilling of an onshore well. The cuttings which were spread at the rate of 600 g HC m{sup -2} contained 10% of fuel oil hydrocarbons (HC). Another part of the field was left untreated. Three months after HC spreading, HC adapted bacteria and fungi were isolated at different soil depths in the two plots and identified. The biodegradation potential of the isolated strains was monitored by measuring the degradation rate of total HC, saturated hydrocarbons, aromatic hydrocarbons and resins of the fuel. Bacteria of the genera Pseudomonas, Brevundimonas, Sphingomonas, Acinetobacter, Rhodococcus, Arthrobacter, Corynebacterium and fungi belonging to Aspergillus, Penicillium, Beauveria, Acremonium, Cladosporium, Fusarium, and Trichoderma were identified. The most active strains in the assimilation of saturates and aromatics were Arthrobacter sp., Sphingomonas spiritivorum, Acinetobacter baumanii, Beauveria alba and Penicillum simplicissimum. The biodegradation potential of the hydrocarbon utilizing microorganisms isolated from polluted or unpolluted soils were similar. In laboratory pure cultures, saturated HC were more degraded than aromatic HC, whereas resins were resistant to microbial attack. On an average, individual bacterial strains were more active than fungi in HC biodegradation

  2. How consistent are top-down hydrocarbon emissions based on formaldehyde observations from GOME-2 and OMI?

    Science.gov (United States)

    Stavrakou, T.; Müller, J.-F.; Bauwens, M.; De Smedt, I.; Van Roozendael, M.; De Mazière, M.; Vigouroux, C.; Hendrick, F.; George, M.; Clerbaux, C.; Coheur, P.-F.; Guenther, A.

    2015-10-01

    The vertical columns of formaldehyde (HCHO) retrieved from two satellite instruments, the Global Ozone Monitoring Instrument-2 (GOME-2) on Metop-A and the Ozone Monitoring Instrument (OMI) on Aura, are used to constrain global emissions of HCHO precursors from open fires, vegetation and human activities in the year 2010. To this end, the emissions are varied and optimized using the adjoint model technique in the IMAGESv2 global CTM (chemical transport model) on a monthly basis and at the model resolution. Given the different local overpass times of GOME-2 (09:30 LT) and OMI (13:30 LT), the simulated diurnal cycle of HCHO columns is investigated and evaluated against ground-based optical measurements at seven sites in Europe, China and Africa. The modeled diurnal cycle exhibits large variability, reflecting competition between photochemistry and emission variations, with noon or early afternoon maxima at remote locations (oceans) and in regions dominated by anthropogenic emissions, late afternoon or evening maxima over fire scenes, and midday minima in isoprene-rich regions. The agreement between simulated and ground-based columns is generally better in summer (with a clear afternoon maximum at mid-latitude sites) than in winter, and the annually averaged ratio of afternoon to morning columns is slightly higher in the model (1.126) than in the ground-based measurements (1.043). The anthropogenic VOC (volatile organic compound) sources are found to be weakly constrained by the inversions on the global scale, mainly owing to their generally minor contribution to the HCHO columns, except over strongly polluted regions, like China. The OMI-based inversion yields total flux estimates over China close to the bottom-up inventory (24.6 vs. 25.5 TgVOC yr-1 in the a priori) with, however, pronounced increases in the northeast of China and reductions in the south. Lower fluxes are estimated based on GOME-2 HCHO columns (20.6 TgVOC yr-1), in particular over the northeast

  3. Emission characteristics of a turbocharged diesel engine fueled with gas-to-liquids

    Institute of Scientific and Technical Information of China (English)

    WU Tao; ZHANG Wugao; FANG Junhua; HUANG Zhen

    2007-01-01

    Emission characteristics of a turbocharged,intercooled,heavy-duty diesel engine operating on neat gas-toliquids (GTL) and blends of GTL with conventional diesel were investigated and a comparison was made with those of diesel fuel.The results show that nitrogen oxides (NOx),smoke,and particulate matter (PM) emissions can be decreased when operating on GTL and diesel-GTL blends.Engine emissions decrease with an increase of GTL fraction in the blends.Compared with diesel fuel,an engine operatingon GTL can reduce NOx,PM,carbon monoxide (CO),and hydrocarbon (HC) by 23.7%,27.6%,16.6% and 12.9% in ECE R49 13-mode procedure,respectively.Engine speed and load have great influences on emissions when operating on diesel-GTL blends and diesel fuel in the turbocharged diesel engine.The study indicates that GTL is a promisingalternative fuel for diesel engines to reduce emissions.

  4. How consistent are top-down hydrocarbon emissions based on formaldehyde observations from GOME-2 and OMI?

    Directory of Open Access Journals (Sweden)

    T. Stavrakou

    2015-04-01

    Full Text Available The vertical columns of formaldehyde (HCHO retrieved from two satellite instruments, the Global Ozone Monitoring Instrument-2 (GOME-2 on Metop-A and the Ozone Monitoring Instrument (OMI on Aura, are used to constrain global emissions of HCHO precursors from open fires, vegetation and human activities in the year 2010. To this end, the emissions are varied and optimized using the adjoint model technique in the IMAGESv2 global CTM (chemistry-transport model on a monthly basis and at the model resolution. Given the different local overpass times of GOME-2 (09:30 LT and OMI (13:30 LT, the simulated diurnal cycle of HCHO columns is investigated and evaluated against ground-based optical measurements at 7 sites in Europe, China and Africa. The modelled diurnal cycle exhibits large variability, reflecting competition between photochemistry and emission variations, with noon or early afternoon maxima at remote locations (oceans and in regions dominated by anthropogenic emissions, late afternoon or evening maxima over fire scenes, and midday minima in isoprene-rich regions. The agreement between simulated and ground-based columns is found to be generally better in summer (with a clear afternoon maximum at mid-latitude sites than in winter, and the annually averaged ratio of afternoon to morning columns is slightly higher in the model (1.126 than in the ground-based measurements (1.043. The anthropogenic VOC (volatile organic compound sources are found to be weakly constrained by the inversions on the global scale, mainly owing to their generally minor contribution to the HCHO columns, except over strongly polluted regions, like China. The OMI-based inversion yields total flux estimates over China close to the bottom-up inventory (24.6 vs. 25.5 in the a priori with, however, pronounced increases in the Northeast China and reductions in the south. Lower fluxes are estimated based on GOME-2 HCHO columns (20.6 TgVOC, in particular over the Northeast, likely

  5. How consistent are top-down hydrocarbon emissions based on formaldehyde observations from GOME-2 and OMI?

    Energy Technology Data Exchange (ETDEWEB)

    Stavrakou, T. [Belgium Inst. for Space Aeronomy, Brussels (Belgium); Muller, J. F. [Belgium Inst. for Space Aeronomy, Brussels (Belgium); Bauwens, M. [Belgium Inst. for Space Aeronomy, Brussels (Belgium); De Smedt, I. [Belgium Inst. for Space Aeronomy, Brussels (Belgium); Van Roozendael, M. [Belgium Inst. for Space Aeronomy, Brussels (Belgium); De Maziere, M. [Belgium Inst. for Space Aeronomy, Brussels (Belgium); Vigouroux, C. [Belgium Inst. for Space Aeronomy, Brussels (Belgium); Hendrick, F. [Belgium Inst. for Space Aeronomy, Brussels (Belgium); George, M. [UPMC Univ., Paris (France); Clerbaux, C. [UPMC Univ., Paris (France); Free University of Brussels (Germany); Coheur, P-F [Free University of Brussels (Germany); Guenther, Alex B. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2015-10-26

    The vertical columns of formaldehyde (HCHO) retrieved from two satellite instruments, the Global Ozone Monitoring Instrument-2 (GOME-2) on Metop-A and the Ozone Monitoring Instrument (OMI) on Aura, are used to constrain global emissions of HCHO precursors from open fires, vegetation and human activities in the year 2010. To this end, the emissions are varied and optimized using the ad-joint model technique in the IMAGESv2 global CTM (chem-ical transport model) on a monthly basis and at the model res-olution. Given the different local overpass times of GOME- 2 (09:30 LT) and OMI (13:30 LT), the simulated diurnal cy-cle of HCHO columns is investigated and evaluated against ground-based optical measurements at seven sites in Europe, China and Africa. The modeled diurnal cycle exhibits large variability, reflecting competition between photochemistry and emission variations, with noon or early afternoon max-ima at remote locations (oceans) and in regions dominated by anthropogenic emissions, late afternoon or evening max-ima over fire scenes, and midday minima in isoprene-rich re-gions. The agreement between simulated and ground-based columns is generally better in summer (with a clear after-noon maximum at mid-latitude sites) than in winter, and the annually averaged ratio of afternoon to morning columns is slightly higher in the model (1.126) than in the ground-based measurements (1.043).The anthropogenic VOC (volatile organic compound) sources are found to be weakly constrained by the inversions on the global scale, mainly owing to their generally minor contribution to the HCHO columns, except over strongly pol-luted regions, like China. The OMI-based inversion yields total flux estimates over China close to the bottom-up inven-tory (24.6 vs. 25.5 TgVOC yr-1 in the a priori) with, how-ever, pronounced increases in the northeast of China and re-ductions in the south. Lower fluxes are estimated based on GOME-2 HCHO columns (20.6 TgVOC yr-1), in

  6. Performance evaluation of Samsung LABGEO(HC10) Hematology Analyzer.

    Science.gov (United States)

    Park, Il Joong; Ahn, Sunhyun; Kim, Young In; Kang, Seon Joo; Cho, Sung Ran

    2014-08-01

    The Samsung LABGEO(HC10) Hematology Analyzer (LABGEO(HC10)) is a recently developed automated hematology analyzer that uses impedance technologies. The analyzer provides 18 parameters including 3-part differential at a maximum rate of 80 samples per hour. To evaluate the performance of the LABGEO(HC10). We evaluated precision, linearity, carryover, and relationship for complete blood cell count parameters between the LABGEO(HC10) and the LH780 (Beckman Coulter Inc) in a university hospital in Korea according to the Clinical and Laboratory Standards Institute guidelines. Sample stability and differences due to the anticoagulant used (K₂EDTA versus K₃EDTA) were also evaluated. The LABGEO(HC10) showed linearity over a wide range and minimal carryover ( 0.92) except for mean corpuscular hemoglobin concentration. The bias estimated was acceptable for all parameters investigated except for monocyte count. Most parameters were stable until 24 hours both at room temperature and at 4°C. The difference by anticoagulant type was statistically insignificant for all parameters except for a few red cell parameters. The accurate results achievable and simplicity of operation make the unit recommendable for small to medium-sized laboratories.

  7. Exergy analysis of an HCFC-22 and HC-290 operated air conditioning system

    Science.gov (United States)

    Ahamed, Jamal Uddin; Raiyan, Muhammad Ferdous; Salam, Md. Abdus

    2017-06-01

    The present work discusses exergy analysis of a split type air conditioning system. Typical domestic air conditioners use R22 which is a Hydrochloroflurocarbon (HCFC) refrigerant. Due to its destructive impact on ozone layer, search for alternative refrigerants is going on. Propane (R290), a pure Hydrocarbon (HC) is considered here along with R22 to make different blends of refrigerants. Two HCFC-22 and HC-290 mixtures (P1 and P2) were prepared with mass ratios of (R22:R290) 90:10 and 85:15 respectively. Using experimentally obtained data of pressure and temperature, other properties in the vapor compression system were found by REFPROP 7 software. Finally, exergy analysis was done for all the refrigerants (R22, P1 and P2). Exergy destruction in each component was also inspected. Total exergy loss of mixture P2 was found to be greater than the exergy loss of R22 and P1. Variations in exergy losses were observed with respect to evaporator temperature at two different ambient conditions. In all cases, exergy destruction in condenser was found to be the highest among the four main components of the cycle.

  8. Long-Term Hydrocarbon Trade Options for the Maghreb Region and Europe—Renewable Energy Based Synthetic Fuels for a Net Zero Emissions World

    Directory of Open Access Journals (Sweden)

    Mahdi Fasihi

    2017-02-01

    Full Text Available Concerns about climate change and increasing emission costs are drivers for new sources of fuels for Europe. Sustainable hydrocarbons can be produced synthetically by power-to-gas (PtG and power-to-liquids (PtL facilities, for sectors with low direct electrification such as aviation, heavy transportation and chemical industry. Hybrid PV–Wind power plants can harvest high solar and wind potentials of the Maghreb region to power these systems. This paper calculates the cost of these fuels for Europe, and presents a respective business case for the Maghreb region. Calculations are hourly resolved to find the least cost combination of technologies in a 0.45° × 0.45° spatial resolution. Results show that, for 7% weighted average cost of capital (WACC, renewable energy based synthetic natural gas (RE-SNG and RE-diesel can be produced in 2030 for a minimum cost of 76 €/MWhHHV (0.78 €/m3SNG and 88 €/MWhHHV (0.85 €/L, respectively. While in 2040, these production costs can drop to 66 €/MWhHHV (0.68 €/m3SNG and 83 €/MWhHHV (0.80 €/L, respectively. Considering access to a WACC of 5% in a de-risking project, oxygen sales and CO2 emissions costs, RE-diesel can reach fuel-parity at crude oil prices of 101 and 83 USD/bbl in 2030 and 2040, respectively. Thus, RE-synthetic fuels could be produced to answer fuel demand and remove environmental concerns in Europe at an affordable cost.

  9. Comparison of the Emission of Aromatic Hydrocarbons from Moulding Sands with Furfural Resin with the Low Content of Furfuryl Alcohol and Different Activators

    Directory of Open Access Journals (Sweden)

    Żymankowska-Kumon S.

    2016-12-01

    Full Text Available No-bake process refers to the use of chemical binders to bond the moulding sand. Sand is moved to the mould fill station in preparation for filling of the mould. A mixer is used to blend the sand with the chemical binder and activator. As the sand exits the mixer, the binder begins the chemical process of hardening. This paper presents the results of decomposition of the moulding sands with modified urea-furfuryl resin (with the low content of furfuryl alcohol below 25 % and different activators: organic and inorganic on a quartz matrix, under semi-industrial conditions. Investigations of the gases emission in the test foundry plant were executed according to the method extended in the Faculty of Foundry Engineering (AGH University of Science and Technology. Article presents the results of the emitted chosen aromatic hydrocarbons and loss on ignition compared with the different activators used to harden this resin. On the bases of the data, it is possible to determine the content of the emitted dangerous substances from the moulding sand according to the content of loss on ignition.

  10. Chemometrics-assisted excitation-emission fluorescence spectroscopy on nylon-attached rotating disks. Simultaneous determination of polycyclic aromatic hydrocarbons in the presence of interferences.

    Science.gov (United States)

    Cañas, Alejandro; Richter, Pablo; Escandar, Graciela M

    2014-12-10

    This work presents a green and very simple approach which enables the accurate and simultaneous determination of benzo[a]pyrene, dibenz[a,h]anthracene, benz[a]anthracene, and chrysene, concerned and potentially carcinogenic heavy-polycyclic aromatic hydrocarbons (PAHs) in interfering samples. The compounds are extracted from water samples onto a device composed of a small rotating Teflon disk, with a nylon membrane attached to one of its surfaces. After extraction, the nylon membrane containing the concentrated analytes is separated from the Teflon disk, and fluorescence excitation-emission matrices are directly measured on the nylon surface, and processed by applying parallel factor analysis (PARAFAC), without the necessity of a desorption step. Under optimum conditions and for a sample volume of 25 mL, the PAHs extraction was carried out in 20 min. Detection limits based on the IUPAC recommended criterion and relative errors of prediction were in the ranges 20-100 ng L(-1) and 5-7%, respectively. Thanks to the combination of the ability of nylon to strongly retain PAHs, the easy rotating disk extraction approach, and the selectivity of second-order calibration, which greatly simplifies sample treatment avoiding the use of toxic solvents, the developed method follows most green analytical chemistry principles.

  11. Hydrocarbon raw emission characterization of a direct-injection spark ignition engine operated with alcohol and furan-based bio fuels

    Energy Technology Data Exchange (ETDEWEB)

    Thewes, Matthias [FEV GmbH, Aachen (Germany); Mauermann, Peter; Pischinger, Stefan [RWTH Aachen Univ. (Germany). Inst. for Combustion Engines; Bluhm, Kerstin; Hollert, Henner [RWTH Aachen Univ. (Germany). Inst. for Environmental Research, Dept. of Ecosystem Analysis

    2013-06-01

    Within the Cluster of Excellence ''Tailor-Made Fuels from Biomass'' the impact of various potential bio fuels on engine combustion is studied. Besides alcohols, furan-based bio fuels have come into the focus with novel production routes to transform biomass into 2-Methylfuran or 2,5-Dimethylfuran. In the present study, the influence of these and other bio fuels on the hydrocarbon raw emission spectrum of a direct-injection spark-ignition single cylinder engine is studied experimentally by means of gas chromatographic and mass spectroscopic analysis of exhaust gas samples. The results obtained are compared to operation with conventional EN 228 gasoline fuel. This fuel showed slip of partially carcinogenic aromatic fuel molecule(s) in warm and in cold engine conditions. For the bio fuels, slip was found to be significant for the alcohol fuels. The carcinogenic molecule 1,3-Butadiene was present in the exhaust gas of all fuels. Furan as another possibly carcinogenic molecule was found at significantly higher concentrations in the exhaust gas of the furan-based bio fuels compared to conventional gasoline fuel but not in the exhaust gas of the alcohol fuels. (orig.)

  12. Detection of HC/sup 18/O/sup +/ in Sagittarius B2

    Energy Technology Data Exchange (ETDEWEB)

    Guelin, M.; Thaddeus, P.

    1979-02-01

    Line emission at 85.1 GHz attributed to the J=1..-->..O rotational transition of the formyl ion HC/sup 18/O/sup +/ has been detected in Sgr B2 (OH). The double isotopic ratio (/sup 16/O//sup 18/O)/(/sup 12/C//sup 13/C) in the formyl ion in Sgr B2 is estimated to be in the range 5--10, hence within a factor 2 of the terrestrial value 5.5. This determination implies that the /sup 13/C//sup 12/C ratio near the galactic center does not differ greatly from that in local molecular clouds.

  13. Detection of HC/O-18//plus/ in Sagittarius B2

    Science.gov (United States)

    Guelin, M.; Thaddeus, P.

    1979-01-01

    Line emission at 85.1 GHz attributed to the J equals 1-0 rotational transition of the formyl ion HC(O-18)(plus) has been detected in Sgr B2 (OH). The double isotopic ratio (O-16/O-18)/(C-12/C-13) in the formyl ion in Sgr B2 is estimated to be in the range 5-10, hence within a factor 2 of the terrestrial value of 5.5. This determination implies that the C-13/C-12 ratio near the galactic center does not differ greatly from that in local molecular clouds.

  14. K2 & HC 结构学习算法%K2 & HC Structure Learning Algorithm

    Institute of Scientific and Technical Information of China (English)

    吴永广; 庞世春

    2014-01-01

    Bayesian network plays an important role in the field of artificial intelligence .The capability of learning knowledge from data makes it develop rapidly in medicine ,fault diagnosis ,forecasting and other fields .Structure learning al-gorithm of Bayesian network becomes an important research area ,which can effectively analyze dependencies between varia-bles and discover knowledge and data properly .Hill-Climbing strategy can reduce the complex solution space and improve the performance of structure learning algorithm .At the same time ,the K2 algorithm is outstanding on the performance of sco-ring .Combined the scoring function of K2 with the efficient Hill-Climbing strategy ,the K2&HC algorithm is proposed . Meanwhile ,Backtracking principle integrates into the search strategy to solve the problem about the structure learning algo-rithm converging to a local optimum ,which can optimize the performance of the algorithm .Contrast with K2 and K2SA sim-ulation ,the conclusions are made that K2&HC algorithm is outstanding on the comprehensive performance of the accuracy and convergence rate .%贝叶斯网络理论在人工智能领域发挥着重要作用。贝叶斯网络从数据中学习知识的能力使得它在医学、故障诊断、预测等领域的应用迅速发展起来。结构学习算法成为贝叶斯网络的重要研究方向,它能够有效分析变量之间依赖关系,合理挖掘数据和知识。K2算法评分性能突出,而爬山算法能有效弥补K2评分法的解空间过于复杂的问题。论文结合K2评分函数和爬山策略,提出了K2&HC算法。同时,K2&HC算法在爬山策略中融入了回溯原理,解决了贝叶斯结构学习算法中存在的收敛于局部最优的问题,合理优化了算法的性能。同K2和K2SA算法进行仿真对比,得出在精度和收敛速度综合性能上K2&HC表现突出的结论。

  15. Power train and emission control: allocation procedure by OBD-II system for automotive technology

    Science.gov (United States)

    Kalita, Porag

    2017-06-01

    OBD-II, systems were designed to maintain low emissions of in use vehicles, including light and medium duty vehicles. In 1989, the California code of Regulations (CCR) known as OBD - II was adopted by the California Air Resource Board (CARB) and the objective to reduce hydrocarbon (HC) emission caused by malfunction of the vehicles emission control systems. OBD-II provides additional information to engineer for diagnosis and repair of emissions related problems. OBD-II, standardizes on the amount of memory (Freeze Frame) it uses to store the readings of the vehicle sensor when it logs on emission related Intermittent Trouble code (IT). The intent of OBD-II, systems is to detect most vehicle malfunctions when performance of a power train component or system deteriorates to the point that the vehicle’s HC emission exceed standard. The vehicle operator is notified at the time when the vehicle begins to marginally exceed emission standards, by illuminating the Malfunctions Indicator Light (MIL).

  16. Unsaturated cuticular hydrocarbons synergize responses to sex attractant pheromone in the yellow peach moth, Conogethes punctiferalis.

    Science.gov (United States)

    Xiao, Wei; Matsuyama, Shigeru; Ando, Tetsu; Millar, Jocelyn G; Honda, Hiroshi

    2012-09-01

    Four trienyl hydrocarbons, (Z3, Z6, Z9)-tricosatriene (Z3, Z6, Z9-23:HC), (Z3, Z6, Z9)-pentacosatriene (Z3, Z6, Z9-25:HC), (Z3, Z6, Z9)-heptacosatriene (Z3, Z6, Z9-27:HC), and (Z3, Z6, Z9)-nonacosatriene (Z3, Z6, Z9-29:HC) were identified in a non-polar fraction of the body wax of male and female yellow peach moth, Conogethes punctiferalis. The relative amounts and ratios of these hydrocarbons differed between sexes. In females, the ratios in body wax and pheromone gland extracts were similar, with lesser amounts found in gland extracts. Synergistic effects of these hydrocarbons when added to the known aldehyde pheromone components were assessed in wind tunnel tests. A blend of (E)-10-hexadecenal (E10-16: Ald) and (Z)-10-hexadecenal (Z10-16: Ald) elicited upwind flight and orientation of males to the pheromone source, but arriving males did not remain close to source for very long. Among the hydrocarbons identified, only Z3, Z6, Z9-23:HC enhanced the activity of the aldehyde blend by increasing the time spent close to the source and the number of source contacts. Z3, Z6, Z9-23:HC and (Z9)-heptacosene (Z9-27:HC) also increased close-range responses to the aldehyde blend. The activity of the aldehyde blend plus these two hydrocarbons was similar to that of crude pheromone extract. Positive dose-response relationships between the aldehyde blend and two hydrocarbon mixtures were found. The lowest doses that elicited synergism were 10(-1) female equivalents (of body wax extracts) for the two hydrocarbons, and 10(-2) female equivalents for the total unsaturated hydrocarbon mixture.

  17. 40 CFR 86.317-79 - Hydrocarbon analyzer specifications.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 18 2010-07-01 2010-07-01 false Hydrocarbon analyzer specifications....317-79 Hydrocarbon analyzer specifications. (a) Hydrocarbon measurements are to be made with a heated... measures hydrocarbon emissions on a dry basis is permitted for gasoline-fueled testing; Provided,...

  18. Characterization of polycyclic aromatic hydrocarbons in fugitive PM10 emissions from an integrated iron and steel plant.

    Science.gov (United States)

    Khaparde, V V; Bhanarkar, A D; Majumdar, Deepanjan; Rao, C V Chalapati

    2016-08-15

    Fugitive emissions of PM10 (particles blast furnace and steel manufacturing unit in an integrated iron and steel plant situated in India. Concentrations of PM10, PM10-bound total PAHs, benzo (a) pyrene, carcinogenic PAHs and combustion PAHs were found to be highest around the sintering unit. Concentrations of 3-ring and 4-ring PAHs were recorded to be highest in the coking unit whereas 5-and 6-ring PAHs were found to be highest in other units. The following indicatory PAHs were identified: indeno (1,2,3-cd) pyrene, dibenzo (a,h) anthracene, benzo (k) fluoranthene in blast furnace unit; indeno (1,2,3-cd) pyrene, dibenzo (a,h) anthracene, chrysene in sintering unit; Anthracene, fluoranthene, chrysene in coking unit and acenaphthene, fluoranthene, fluorene in steel making unit. Total-BaP-TEQ (Total BaP toxic equivalent quotient) and BaP-MEQ (Total BaP mutagenic equivalent quotient) concentration levels ranged from 2.4 to 231.7ng/m(3) and 1.9 to 175.8ng/m(3), respectively. BaP and DbA (dibenzo (a,h) anthracene) contribution to total-BaP-TEQ was found to be the highest.

  19. Diurnal variations of ambient particulate wood burning emissions and their contribution to the concentration of Polycyclic Aromatic Hydrocarbons (PAHs in Seiffen, Germany

    Directory of Open Access Journals (Sweden)

    L. Poulain

    2011-12-01

    Full Text Available Residential wood burning is becoming an increasingly important cause of air quality problems since it has become a popular source of alternative energy to fossil fuel. In order to characterize the contribution of residential wood burning to local particle pollution, a field campaign was organized at the village of Seiffen (Saxony, Germany. During this campaign, an Aerosol Mass Spectrometer (AMS was deployed in parallel to a PM1 high volume filter sampler. The AMS mass spectra were analyzed using Positive Matrix Factorization (PMF to obtain detailed information about the organic aerosol (OA. Biomass-burning organic aerosol (BBOA, Hydrocarbon-like organic aerosol (HOA, and Oxygenated Organic Aerosol (OOA were identified and represented 20%, 17% and 62% of total OA, respectively. Additionally, Polycyclic Aromatic Hydrocarbons (PAH were measured by the AMS with an average concentration of 10 ng m−3 and short term events of extremely high PAH concentration (up to 500 ng m−3 compared to the mean PAH value were observed during the whole measurement period. A comparison with the results from PM1 filter samples showed that the BBOA factor and the AMS PAH are good indicators of the total concentration of the different monosaccharide anhydrides and PAH measured on the filter samples. Based on its low correlation with CO and the low car traffic, the HOA factor was considered to be related to residential heating using liquid fuel. An influence of the time of the week (week vs. weekend on the diurnal profiles of the different OA components was observed. The weekdays were characterized by two maxima; a first one early in the morning and a stronger one in the evening. During the weekend days, the different OA components principally reached only one maximum in the afternoon. Finally, the PAH emitted directly from residential wood combustion was estimated to represent 1.5% of the total mass of the BBOA factor and

  20. Preparation and emission characteristics of ethanol-diesel fuel blends

    Institute of Scientific and Technical Information of China (English)

    ZHANG Run-duo; HE Hong; SHI Xiao-yan; ZHANG Chang-bin; HE Bang-quan; WANG Jian-xin

    2004-01-01

    The preparation of ethanol-diesel fuel blends and their emission characteristics were investigated. Results showed the absolute ethanol can dissolve in diesel fuel at an arbitrary ratio and a small quantity of water(0.2%) addition can lead to the phase separation of blends. An organic additive was synthesized and it can develop the ability of resistance to water and maintain the stability of ethanol-diesel-trace amounts of water system. The emission characteristics of 10%, 20%, and 30% ethanol-diesel fuel blends, with or without additives, were compared with those of diesel fuel in a direct injection(DI) diesel engine. The experimental results indicated that the blend of ethanol with diesel fuel significantly reduced the concentrations of smoke, hydrocarbon(HC), and carbon monoxide(CO) in exhaust gas. Using 20% ethanol-diesel fuel blend with the additive of 2% of the total volume, the optimum mixing ratio was achieved, at which the bench diesel engine testing showed a significant decrease in exhaust gas. Bosch smoke number was reduced by 55%, HC emission by 70%, and CO emission by 45%, at 13 kW/1540 r/min. However, ethanol-diesel fuel blends produced a few ppm acetaldehydes and more ethanol in exhaust gas.

  1. Exhaust emissions from a diesel power generator fuelled by waste cooking oil biodiesel.

    Science.gov (United States)

    Valente, Osmano Souza; Pasa, Vanya Márcia Duarte; Belchior, Carlos Rodrigues Pereira; Sodré, José Ricardo

    2012-08-01

    The exhaust emissions from a diesel power generator operating with waste cooking oil biodiesel blends have been studied. Fuel blends with 25%, 50% and 75% of biodiesel concentration in diesel oil were tested, varying engine load from 0 to 25 kW. The original engine settings for diesel oil operation were kept the same during the experiments with the biodiesel blends. The main physical-chemical characteristics of the fuel blends used were measured to help with the analysis of the emission results. The results show that the addition of biodiesel to the fuel increases oxides of nitrogen (NO(X)), carbon monoxide (CO) and hydrocarbon (HC) emissions. Carbon dioxide (CO(2)) and exhaust gas opacity were also increased with the use of biodiesel. Major increase of NO(X) was observed at low loads, while CO and HC were mainly increased at high loads. Using 50% of biodiesel in diesel oil, the average increase of CO(2), CO, HC and NO(X) throughout the load range investigated was 8.5%, 20.1%, 23.5% and 4.8%, respectively. Copyright © 2012 Elsevier B.V. All rights reserved.

  2. A Study on the Model of Traffic Flow and Vehicle Exhaust Emission

    Directory of Open Access Journals (Sweden)

    Han Xue

    2013-01-01

    Full Text Available The increase of traffic flow in cities causes traffic congestion and accidents as well as air pollution. Traffic problems have attracted the interest of many researchers from the perspective of theory and engineering. In order to provide a simple and practical method for measuring the exhaust emission and assessing the effect of pollution control, a model is based on the relationship between traffic flow and vehicle exhaust emission under a certain level of road capacity constraints. In the proposed model, the hydrocarbons (HC, carbon monoxide (CO, and nitrogen oxides (NOx are considered as the indexes of total exhaust emission, and the speed is used as an intermediate variable. To verify the rationality and practicality of the model, a case study for Beijing, China, is provided in which the effects of taxi fare regulation and the specific vehicle emission reduction policy are analyzed.

  3. Isolation and Characterization of Hydrocarbon-Degrading Yeast Strains from Petroleum Contaminated Industrial Wastewater

    Directory of Open Access Journals (Sweden)

    Boutheina Gargouri

    2015-01-01

    Full Text Available Two yeast strains are enriched and isolated from industrial refinery wastewater. These strains were observed for their ability to utilize several classes of petroleum hydrocarbons substrates, such as n-alkanes and aromatic hydrocarbons as a sole carbon source. Phylogenetic analysis based on the D1/D2 variable domain and the ITS-region sequences indicated that strains HC1 and HC4 were members of the genera Candida and Trichosporon, respectively. The mechanism of hydrocarbon uptaking by yeast, Candida, and Trichosporon has been studied by means of the kinetic analysis of hydrocarbons-degrading yeasts growth and substrate assimilation. Biodegradation capacity and biomass quantity were daily measured during twelve days by gravimetric analysis and gas chromatography coupled with mass spectrometry techniques. Removal of n-alkanes indicated a strong ability of hydrocarbon biodegradation by the isolated yeast strains. These two strains grew on long-chain n-alkane, diesel oil, and crude oil but failed to grow on short-chain n-alkane and aromatic hydrocarbons. Growth measurement attributes of the isolates, using n-hexadecane, diesel oil, and crude oil as substrates, showed that strain HC1 had better degradation for hydrocarbon substrates than strain HC4. In conclusion, these yeast strains can be useful for the bioremediation process and decreasing petroleum pollution in wastewater contaminated with petroleum hydrocarbons.

  4. Isolation and Characterization of Hydrocarbon-Degrading Yeast Strains from Petroleum Contaminated Industrial Wastewater

    Science.gov (United States)

    Gargouri, Boutheina; Mhiri, Najla; Karray, Fatma; Aloui, Fathi; Sayadi, Sami

    2015-01-01

    Two yeast strains are enriched and isolated from industrial refinery wastewater. These strains were observed for their ability to utilize several classes of petroleum hydrocarbons substrates, such as n-alkanes and aromatic hydrocarbons as a sole carbon source. Phylogenetic analysis based on the D1/D2 variable domain and the ITS-region sequences indicated that strains HC1 and HC4 were members of the genera Candida and Trichosporon, respectively. The mechanism of hydrocarbon uptaking by yeast, Candida, and Trichosporon has been studied by means of the kinetic analysis of hydrocarbons-degrading yeasts growth and substrate assimilation. Biodegradation capacity and biomass quantity were daily measured during twelve days by gravimetric analysis and gas chromatography coupled with mass spectrometry techniques. Removal of n-alkanes indicated a strong ability of hydrocarbon biodegradation by the isolated yeast strains. These two strains grew on long-chain n-alkane, diesel oil, and crude oil but failed to grow on short-chain n-alkane and aromatic hydrocarbons. Growth measurement attributes of the isolates, using n-hexadecane, diesel oil, and crude oil as substrates, showed that strain HC1 had better degradation for hydrocarbon substrates than strain HC4. In conclusion, these yeast strains can be useful for the bioremediation process and decreasing petroleum pollution in wastewater contaminated with petroleum hydrocarbons. PMID:26339653

  5. Isolation and Characterization of Hydrocarbon-Degrading Yeast Strains from Petroleum Contaminated Industrial Wastewater.

    Science.gov (United States)

    Gargouri, Boutheina; Mhiri, Najla; Karray, Fatma; Aloui, Fathi; Sayadi, Sami

    2015-01-01

    Two yeast strains are enriched and isolated from industrial refinery wastewater. These strains were observed for their ability to utilize several classes of petroleum hydrocarbons substrates, such as n-alkanes and aromatic hydrocarbons as a sole carbon source. Phylogenetic analysis based on the D1/D2 variable domain and the ITS-region sequences indicated that strains HC1 and HC4 were members of the genera Candida and Trichosporon, respectively. The mechanism of hydrocarbon uptaking by yeast, Candida, and Trichosporon has been studied by means of the kinetic analysis of hydrocarbons-degrading yeasts growth and substrate assimilation. Biodegradation capacity and biomass quantity were daily measured during twelve days by gravimetric analysis and gas chromatography coupled with mass spectrometry techniques. Removal of n-alkanes indicated a strong ability of hydrocarbon biodegradation by the isolated yeast strains. These two strains grew on long-chain n-alkane, diesel oil, and crude oil but failed to grow on short-chain n-alkane and aromatic hydrocarbons. Growth measurement attributes of the isolates, using n-hexadecane, diesel oil, and crude oil as substrates, showed that strain HC1 had better degradation for hydrocarbon substrates than strain HC4. In conclusion, these yeast strains can be useful for the bioremediation process and decreasing petroleum pollution in wastewater contaminated with petroleum hydrocarbons.

  6. Final Report of a CRADA Between Pacific Northwest National Laboratory and the Ford Motor Company (CRADA No. PNNL/265): “Deactivation Mechanisms of Base Metal/Zeolite Urea Selective Catalytic Reduction Materials, and Development of Zeolite-Based Hydrocarbon Adsorber Materials”

    Energy Technology Data Exchange (ETDEWEB)

    Gao, Feng; Kwak, Ja Hun; Lee, Jong H.; Tran, Diana N.; Peden, Charles HF; Howden, Ken; Cheng, Yisun; Lupescu, Jason; Cavattaio, Giovanni; Lambert, Christine; McCabe, Robert W.

    2013-02-14

    Reducing NOx emissions and particulate matter (PM) are primary concerns for diesel vehicles required to meet current LEV II and future LEV III emission standards which require 90+% NOx conversion. Currently, urea SCR as the NOx reductant and a Catalyzed Diesel Particulate Filter (CDPF) are being used for emission control system components by Ford Motor Company for 2010 and beyond diesel vehicles. Because the use of this technology for vehicle applications is new, the relative lack of experience makes it especially challenging to satisfy durability requirements. Of particular concern is being able to realistically simulate actual field aging of the catalyst systems under laboratory conditions. This is necessary both as a rapid assessment tool for verifying improved performance and certifiability of new catalyst formulations, and to develop a good understanding of deactivation mechanisms that can be used to develop improved catalyst materials. In addition to NOx and PM, the hydrocarbon (HC) emission standards are expected to become much more stringent during the next few years. Meanwhile, the engine-out HC emissions are expected to increase and/or be more difficult to remove. Since HC can be removed only when the catalyst becomes warm enough for its oxidation, three-way catalyst (TWC) and diesel oxidation catalyst (DOC) formulations often contain proprietary zeolite materials to hold the HC produced during the cold start period until the catalyst reaches its operating temperature (e.g., >200°C). Unfortunately, much of trapped HC tends to be released before the catalyst reaches the operating temperature. Among materials effective for trapping HC during the catalyst warm-up period, siliceous zeolites are commonly used because of their high surface area and high stability under typical operating conditions. However, there has been little research on the physical properties of these materials related to the adsorption and release of various hydrocarbon species found in

  7. Identification and quantification of known polycyclic aromatic hydrocarbons and pesticides in complex mixtures using fluorescence excitation-emission matrices and parallel factor analysis.

    Science.gov (United States)

    Ferretto, Nicolas; Tedetti, Marc; Guigue, Catherine; Mounier, Stéphane; Redon, Roland; Goutx, Madeleine

    2014-07-01

    Polycyclic aromatic hydrocarbons (PAHs) and pesticides are among the most widespread organic contaminants in aquatic environments. Because of their aromatic structure, PAHs and pesticides have intrinsic fluorescence properties in the ultraviolet/blue spectral range. In this study, excitation-emission matrix (EEM) fluorescence spectroscopy and parallel factor (PARAFAC) analysis were used to characterise and discriminate fluorescence signatures of nine PAHs and three pesticides at the μg L(-1) level in the presence of humic substances (0.1-10 mgCL(-1)). These contaminants displayed a diversity of fluorescence signatures regarding spectral position (λEx: 220-335 nm, λEm: 310-414 nm), Stokes shift (39-169 nm) and number of peaks (1-8), with detection limits ranging from 0.02 to 1.29μgL(-1). The EEM/PARAFAC method applied to mixtures of PAHs with humic substances validated a seven-component model that included one humic-like fluorophore and six PAH-like fluorophores. The EEM/PARAFAC method applied to mixtures of pesticides with humic substances validated a six-component model that included one humic-like fluorophore and three pesticide-like fluorophores. The EEM/PARAFAC method adequately quantified most of the contaminants for humic substance concentrations not exceeding 2.5 mg CL(-1). The application of this method to natural (marine) samples was demonstrated through (1) the match between the Ex and Em spectra of PARAFAC components and the Ex and Em spectra of standard PAHs, and (2) the good linear correlations between the fluorescence intensities of PARAFAC components and the PAH concentrations determined by GC-MS.

  8. Polycyclic aromatic hydrocarbons (PAHs) in exhaust emissions from diesel engines powered by rapeseed oil methylester and heated non-esterified rapeseed oil

    Science.gov (United States)

    Vojtisek-Lom, Michal; Czerwinski, Jan; Leníček, Jan; Sekyra, Milan; Topinka, Jan

    2012-12-01

    Polycyclic aromatic hydrocarbons (PAHs) of exhaust emissions were studied in four direct-injection turbocharged four-cylinder diesel engines, with power ratings of 90-136 kW. The engines were operated on biodiesel (B-100), a blend of 30% biodiesel in diesel fuel (B-30), and heated rapeseed oil (RO) in two independent laboratories. Diesel particle filters (DPF) and selective catalytic reduction (SCR) systems were used with B-30 and B-100. Concentrations of individual PAHs sampled in different substrates (quartz, borosilicate fiber and fluorocarbon membrane filters, polyurethane foam) were analyzed using different methods. Benzo[a]pyrene toxic equivalents (BaP TEQ) were calculated using different sets of toxic equivalency factors (TEF). Operation on B-100 without aftertreatment devices, compared to diesel fuel, yielded a mean reduction in PAHs of 73%, consistent across engines and among TEF used. A lower PAH reduction was obtained using B-30. The BaP TEQ reductions on DPF were 91-99% using B-100, for one non-catalyzed DPF, and over 99% in all other cases. The BaP TEQ for heated RO were higher than those for B-100 and one half lower to over twice as high as that of diesel fuel. B-100 and RO samples featured, compared to diesel fuel, a relatively high share of higher molecular weight PAH and a relatively low share of lighter PAHs. Using different sets of TEF or different detection methods did not consistently affect the observed effect of fuels on BaP TEQ. The compilation of multiple tests was helpful for discerning emerging patterns. The collection of milligrams of particulate matter per sample was generally needed for quantification of all individual PAHs.

  9. π-Extended Star-Shaped Polycyclic Aromatic Hydrocarbons based on Fused Truxenes: Synthesis, Self-Assembly, and Facilely Tunable Emission Properties.

    Science.gov (United States)

    Cheng, Cheng; Jiang, Yi; Liu, Cheng-Fang; Zhang, Jian-Dong; Lai, Wen-Yong; Huang, Wei

    2016-12-19

    A new set of star-shaped polycyclic aromatic hydrocarbons (PAHs) based on naphthalene-fused truxenes, TrNaCn (n=1-4), were synthesized and characterized. The synthesis involved a microwave-assisted six-fold Suzuki coupling reaction, followed by oxidative cyclodehydrogenation. Multiple dehydrocyclization products could be effectively isolated in a single reaction, thus suggesting that the oxidative cyclodehydrogenation reaction involved a stepwise ring-closing process. The thermal, optical, and electrochemical properties and the self-assembly behavior of the resulting oxidized samples were investigated to understand the impact of the ring-fusing process on the properties of the star-shaped PAHs. Distinct bathochromic shift of the absorption maxima (λmax ) revealed that the molecular conjugation extended with the stepwise ring-closing reactions. The optical band-gap energy of these PAHs varied significantly on increasing the number of fused rings, thereby resulting in readily tunable emissive properties of the resultant star-shaped PAHs. Interestingly, the generation of rigid "arms" by using perylene analogues caused TrNaC2 and TrNaC3 to show significantly enhanced photoluminescence quantum yields (PLQYs) in solution (η=0.65 and 0.66, respectively) in comparison with those of TrNa and TrNaC1 (η=0.08 and 0.16, respectively). Owing to strong intermolecular interactions, the TrNa precursor was able to self-assemble into rod-like microcrystals, which could be facilely identified by the naked eye, whilst TrNaC1 self-assembled into nanosheets once the naphthalene rings had fused. This study offers a unique platform to gain further insight into-and a better understanding of-the photophysical and self-assembly properties of π-extended star-shaped PAHs.

  10. Emissions of aldehydes and ketones from a two-stroke engine using ethanol and ethanol-blended gasoline as fuel.

    Science.gov (United States)

    Magnusson, Roger; Nilsson, Calle; Andersson, Barbro

    2002-04-15

    Besides aliphatic gasoline, ethanol-blended gasoline intended for use in small utility engines was recently introduced on the Swedish market. For small utility engines, little data is available showing the effects of these fuels on exhaust emissions, especially concerning aldehydes and ketones (carbonyls). The objective of the present investigation was to study carbonyl emissions and regulated emissions from a two-stroke chain saw engine using ethanol, gasoline, and ethanol-blended gasoline as fuel (0%, 15%, 50%, 85%, and 100% ethanol). The effects of the ethanol-blending level and mechanical changes of the relative air/fuel ratio, lambda, on exhaust emissions was investigated, both for aliphatic and regular gasoline. Formaldehyde, acetaldehyde, and aromatic aldehydes were the most abundant carbonyls in the exhaust. Acetaldehyde dominated for all ethanol-blended fuels (1.2-12 g/kWh, depending on the fuel and lambda), and formaldehyde dominated for gasoline (0.74-2.3 g/kWh, depending on the type of gasoline and lambda). The main effects of ethanol blending were increased acetaldehyde emissions (30-44 times for pure ethanol), reduced emissions of all other carbonyls exceptformaldehyde and acrolein (which showed a more complex relation to the ethanol content), reduced carbon monoxide (CO) and ntirogen oxide (NO) emissions, and increased hydrocarbon (HC) and nitrogen dixodie (NO2) emissions. The main effects of increasing lambda were increased emissions of carbonyls and nitrogen oxides (NOx) and reduced CO and HC emissions. When the two types of gasoline are considered, benzaldehyde and tolualdehyde could be directly related to the gasoline content of aromatics or olefins, but also acrolein, propanal, crotonaldehyde, and methyl ethyl ketone mainly originated from aromatics or olefins, while the main source for formaldehyde, acetaldehyde, acetone, methacrolein, and butanal was saturated aliphatic hydrocarbons.

  11. Study on the Interaction Coefficients in PR Equation with vdW Mixing Rules for HFC and HC Binary Mixtures

    Science.gov (United States)

    Chen, Jian-Xin; Hu, Peng; Chen, Ze-Shao

    2008-12-01

    The Peng-Robinson equation of state with the van der Waals mixing rules was used to correlate vapor-liquid equilibrium (VLE) data for HFC/HC, HFC/HFC, and HC/HC binary mixtures. The interaction parameter k ij was obtained for every binary mixture. It was assumed that k ij has contributions from the two components, and each component has its own constant contribution factor k i for the mixture, and the values of k ij indicate the degree in difference of properties between the two components. Therefore, the interaction parameters k ij is proposed as: k ij = k i - k j . The values of the mixing factor k i for Hydrofluorocarbons (HFCs) and Hydrocarbons (HCs), including propane, isobutane, n-butane, R23, R32, R125, R143a, R134a, R152a, R227ea R236fa, R236ea, and R245fa, were obtained by least-square fitting. In total, 39 refrigerant binary mixtures were analyzed on the basis of this method, and the results showed good agreement with experimental data. The overall average absolute deviations of pressure and vapor mole fraction are 1.3 % and 0.0089, respectively.

  12. Application of pyrolysis gas chromatography technique to evaluation of coal-generated hydrocarbon

    Institute of Scientific and Technical Information of China (English)

    孙永革; 盛国英; 傅家谟

    1997-01-01

    Based on kerogen-generated hydrocarbon model, a new method to calculate hydrocarbon yields for coals and coaly samples was put forward by means of pyrolysis technique. At the same time, the empirical criteria suggested by Powell were revised. The threshold value was preliminarily defined as HC yields >30 mg HC per gram TOC for effective gas source rocks and >60 mg HC per gram TOC for effective oil source rocks. Additionally, it was also confirmed that the relative compositions of the three ranges of C1-C5 total hydrocarbons, C6-C14 n-alkanes plus n-alkenes and C15+ n-alkanes plus n-alkenes from pyrolysates can be effectively used to distinguish the coal-generated hydrocarbon types.

  13. Exhaust gas emission from a two-stroke engine

    Energy Technology Data Exchange (ETDEWEB)

    Lippitsch, H.H.; Eichlseder, H.

    1986-01-01

    According to present day ideas, carbon monoxide CO, hydrocarbons HC and nitrogen oxide NO are regarded as harmful substances in the exhaust gas and are therefore limited by law in some countries. After a survey of the regulations in Europe and the USA, the origin of these substances in a two-stroke engine is briefly described. The effect of the type of engine is then shown by results from various engines. It was found that emission can be drastically reduced by new engine designs. The introduction of exhaust gas regulations in Austria has caused the firm of Bombadier-Rotax to intensify their development work in this field. The state of exhaust gas emission of present day mass-produced engines was compared with previous engines at this opportunity.

  14. The discovery of a new infrared emission feature at 1905 wavenumbers (5.25 microns) in the spectrum of BD + 30 deg 3639 and its relation to the polycyclic aromatic hydrocarbon model

    Science.gov (United States)

    Allamandola, L. J.; Bregman, J. D.; Sandford, S. A.; Tielens, A. G. G. M.; Witteborn, F. C.

    1989-01-01

    A new IR emission feature at 1905/cm (5.25 microns) has been discovered in the spectrum of BD + 30 deg 3639. This feature joins the family of well-known IR emission features at 3040, 2940, 1750, 1610, '1310', 1160, and 890/cm. The origin of this new feature is discussed and it is assigned to an overtone or combination band involving C-H bending modes of polycyclic aromatic hydrocarbons (PAHs). Laboratory work suggests that spectral studies of the 2000-1650/cm region may be very useful in elucidating the molecular structure of interstellar PAHs. The new feature, in conjunction with other recently discovered spectral structures, suggests that the narrow IR emission features originate in PAH molecules rather than large carbon grains.

  15. Cyanodiacetylene (HC/sub 5/N) in Sagittarius B2

    Energy Technology Data Exchange (ETDEWEB)

    Avery, L.W.; Oka, T.; Broten, N.W.; MacLeod, J.M.

    1979-07-01

    The J=2..-->..1 and 3..-->..2 rotational transitions of cyanodiacetylene have been observed in Sgr B2. Statistical equilibrium calculations have been carried out to construct a three-component model of the HC/sub 5/N cloud in Sgr B2 which is consistent with these observations, with our earlier observations of the J=1..-->..0.4..-->..3, and 8..-->..7 lines and with the data obtained by Guelin and Thaddeus for the J=31..-->..30 to J=37..-->..36 millimeter-wave transitions. The relative strength of the J=1..-->..0 line requires the presence of an extensive, low-density envelope around the Sgr B2 molecular cloud which serves as a weak 1..-->..0 line maser. This envelope is characterized by an H/sub 2/ density of 100 cm/sup -3/ and a kinetic temperature of about 20 K. The maximum column density of HC/sub 5/N in Sgr B2 is found to be 1.6 x 10/sup 14/ cm/sup -3/, equal to that of HC/sub 3/N.

  16. BACT Fugitive Emissions of Hydrocarbons

    Science.gov (United States)

    This document may be of assistance in applying the New Source Review (NSR) air permitting regulations including the Prevention of Significant Deterioration (PSD) requirements. This document is part of the NSR Policy and Guidance Database. Some documents in the database are a scanned or retyped version of a paper photocopy of the original. Although we have taken considerable effort to quality assure the documents, some may contain typographical errors. Contact the office that issued the document if you need a copy of the original.

  17. Experimental Study on Emissions of Polycyclic Aromatic Hydrocarbons of Unleaded Gasoline%汽油多环芳香烃排放的试验研究

    Institute of Scientific and Technical Information of China (English)

    李西秦; 蔡仁华; 曹淼龙; 刘冰

    2011-01-01

    In order to study the effect of three-way catalytic converter on generation of polycyclic aromatic hydrocarbons (PAH)in gasoline combustion process, tests were made in a HL495IQ electronic fuel injection gasoline engine. The emissions of several kinds of PAHs are measured by a gas chromatography - mass spectrometry (GC-MS) analyzer. The test results show that PAH is generated mainly by fuel which is not burnt completely at exhaust temperature of 200~600 t. With the increase of exhaust temperature to 600-800℃, the fuel will be broken up into more free radicals, which results in more PAH being generated. In three-way catalytic converter, PAH may be synthesized or converted, the nature and reaction condition of PAH determines which trend dominates.%为了解三元催化器对汽油燃烧过程中多环芳香烃生成的影响,在HL495IQ电喷汽油机上进行了台架试验,通过气相色谱一质谱联用(GC-MS)分析仪测试了几种多环芳香烃的排放量.试验结果表明,排气温度在200~600℃时,多环芳香烃主要源于未完全燃烧的燃油;排气温度在600~800℃时,随温度的升高燃油裂解出更多的自由基团,从而促使生成更多的多环芳香烃.在三元催化器中存在着多环芳香烃的合成与转化2个趋势,哪个趋势占主导地位取决于多环芳香烃各白的性质和反应条件.

  18. Experimental investigation of HFC407C/HC290/HC600a mixture in a window air conditioner

    Energy Technology Data Exchange (ETDEWEB)

    Jabaraj, D.B.; Avinash, P.; Lal, D. Mohan; Renganarayan, S. [Department of Mechanical Engineering, College of Engineering, Anna University, Chennai 600 025 (India)

    2006-09-15

    HCFC22, one of the widely used refrigerants in window air conditioners must be phased out soon as per the Montreal protocol. Presently, HFC407C is considered as a potential drop in substitute for HCFC22, but retrofitting HCFC22 systems with HFC407C with polyol ester oil (POE) is a major issue as HFC407C is immiscible with mineral oil. The miscibility issue of HFC407C with mineral oil was overcome with the addition of a HC blend to it. The above technoeconomic feasibility issues to retrofit the existing HCFC22 systems with an ozone friendly refrigerant and retain the energy efficiency of the system are challenges in the air conditioning sector. In this present work, an experimental analysis has been conducted in a window air conditioner retrofitted with eco-friendly refrigerant mixtures of HFC407C/HC290/HC600a without changing the mineral oil. Its performance, as well as energy consumption, was compared with the conventional one. It is observed that the mixtures demand lengthening of the condenser in order to maintain the discharge pressure within acceptable limits. This also resulted in better heat transfer at the condenser. Therefore, in this study, the condenser tube length was increased by 19% to suit the mixtures as compared to HCFC22. Compared to HCFC22, the refrigeration capacity of the new mixture was 9.54-12.76% higher than that of HCFC22, while the actual COP was found to be 11.91-13.24% higher than that of HCFC22. The overall performance has proved that the HFC407C/HC blend refrigerant mixture could be an eco-friendly substitute to phase out HCFC22. (author)

  19. Detection of Interstellar HC5O in TMC-1 with the Green Bank Telescope

    Science.gov (United States)

    McGuire, Brett A.; Burkhardt, Andrew M.; Shingledecker, Christopher N.; Kalenskii, Sergei V.; Herbst, Eric; Remijan, Anthony J.; McCarthy, Michael C.

    2017-07-01

    We report the detection of the carbon-chain radical HC5O for the first time in the interstellar medium toward the cold core TMC-1 using the 100 m Green Bank Telescope. We observe four hyperfine components of this radical in the J=17/2\\to 15/2 rotational transition that originates from the {}2{{{\\Pi }}}1/2 fine structure level of its ground state and calculate an abundance of n/{n}{H2}=1.7× {10}-10, assuming an excitation temperature of {T}{ex}=7 K. No indication of HC3O, HC4O, or HC6O, is found in these or archival observations of the source, while we report tentative evidence for HC7O. We compare calculated upper limits and the abundance of HC5O to predictions based on (1) the abundance trend of the analogous HC n N family in TMC-1 and (2) a gas-grain chemical model. We find that the gas-grain chemical model well reproduces the observed abundance of HC5O, as well as the upper limits of HC3O, HC6O, and HC7O, but HC4O is overproduced. The prospects for astronomical detection of both shorter and longer HC n O chains are discussed.

  20. N2H+ and HC3N Observations of the Orion A Cloud

    CERN Document Server

    Tatematsu, K; Umemoto, T; Sekimoto, Y

    2008-01-01

    The ``integral-shaped filament'' of the Orion A giant molecular cloud was mapped in N2H+, and its northern end, the OMC-2/3 region was observed also in HC3N and CCS. The N2H+ distribution is similar to the dust continuum distribution, except for the central part of the Orion Nebula. The distribution of H13CO+ holds resemblance to that of dust continuum, but the N2H+ distribution looks more similar to dust continuum distribution. The N-bearing molecules, N2H+ and NH3 seem to be more intense in OMC-2, compared with the H13CO+ and CS distribution. We identified 34 cloud cores from N2H+ data. Over the Orion Nebula region, the N2H+ linewidth is large (1.1-2.1 km/s). In the OMC-2/3 region, it becomes moderate (0.5-1.3 km/s), and it is smaller (0.3-1.1 km/s) in the south of the Orion Nebula. On the other hand, the gas kinetic temperature of the quiescent cores observed in N2H+ is rather constant (~ 20 K) over the $\\int$-shaped filament. We detected no CCS emission in the OMC-2/3 region. In general, N2H+ and HC3N dis...

  1. C2H, HC3N and HNC Observations in OMC-2/3

    CERN Document Server

    Liu, Qiang; Sun, Yan; Xu, Ye

    2011-01-01

    For the first time, the OMC-2/3 region was mapped in C2H(1-0), HC3N(10-9) and HNC(1-0) lines. In general, the emissions from all the three molecular species reveal an extended filamentary structure. The distribution of C2H cores almost follows that of the 1300 $\\mu$m condensations, which might suggest that C2H is a good tracer to study the core structure of molecular clouds. The core masses traced by HNC are rather flat, ranging from 18.8 to 49.5 $M_{\\odot}$, while present a large span for those from C2H, ranging from 6.4 to 36.0 $M_{\\odot}$. The line widths of both HNC and C2H look very similar, and both are wider than that of HC3N. The line widths of the three lines are all wider than those from dark clouds, implying that the former is more active than the latter, and has larger turbulence caused by winds and UV radiation from the surrounding massive stars.

  2. C2H, HC3N and HNC observations in OMC-2/3 *

    Institute of Scientific and Technical Information of China (English)

    Qiang Liu; Ji Yang; Yan Sun; Ye Xu

    2011-01-01

    For the first time, the OMC-2/3 region was mapped in C2H (1-0), HC3N (10-9) and HNC (1-0) lines. In general, the emissions from all the three molecular species reveal an extended filamentary structure. The distribution of C2H cores almost follows that of the 1300 μtm condensations, which might suggest that C2H is a good tracer to study the core structure of molecular clouds. The core masses traced by HNC are rather fiat, ranging from 18.8 to 49.5 M⊙, while also presenting a large span for those from C2H, ranging from 6.4 to 36.0 M⊙. The line widths of both HNC and C2H look very similar, and both are wider than that of HC3N. The line widths of the three lines are all wider than those from dark clouds, implying that the former is more active than the latter, and has larger turbulence caused by winds and UV radiation from the surrounding massive stars.

  3. Experimental Investigation of Performance and Emissions of a Stratified Charge CNG Direct Injection Engine with Turbocharger

    Directory of Open Access Journals (Sweden)

    Amiruddin Hilmi

    2017-01-01

    Full Text Available This paper presents the results from 1.6 litre, 4 cylinders stratified charge compressed natural gas (CNG direct injection engine with boosting device. A turbocharger with compressor trim of 40 was used to increase engine output. The engine was tested at wide open throttle (WOT and speed ranging from 1000 to 5000 rpm. Engine performance and emissions data were recorded under steady state condition. Results show turbocharged CNG engine produced an average of 26% increment in brake power and 24% additional maximum brake torque as compared with natural aspirated (NA CNG engine. Turbocharged CNG engine improved brake specific fuel consumption (BSFC and yielded higher fuel conversion efficiency (FCE. Relatively turbocharged CNG engine showed lower emission of hydrocarbon (HC and carbon monoxide (CO throughout tested engine speed. Conversely, the carbon dioxide (CO2 and nitrogen oxide (NOx emission produced were slightly higher compared with NA CNG engine.

  4. Detection of the HC3NH+ and HCNH+ ions in the L1544 pre-stellar core

    Science.gov (United States)

    Quénard, D.; Vastel, C.; Ceccarelli, C.; Hily-Blant, P.; Lefloch, B.; Bachiller, R.

    2017-09-01

    The L1544 pre-stellar core was observed as part of the ASAI (Astrochemical Surveys At IRAM) Large Program. We report the first detection in a pre-stellar core of the HCNH+ and HC3NH+ ions. The high spectral resolution of the observations allows us to resolve the hyperfine structure of HCNH+. Local thermodynamic equilibrium (LTE) analysis leads to derive a column density equal to (2.0 ± 0.2) × 1013 cm-2 for HCNH+ and (1.5 ± 0.5) × 1011 cm-2 for HC3NH+. We also present non-LTE analysis of five transitions of HC3N, three transitions of H13CN and one transition of HN13C, all of them linked to the chemistry of HCNH+ and HC3NH+. We computed for HC3N, HCN and HNC a column density of (2.0 ± 0.4) × 1013 cm-2, (3.6 ± 0.9) × 1014 cm-2 and (3.0 ± 1.0) × 1014 cm-2, respectively. We used the gas-grain chemical code nautilus to predict the abundances of all these species across the pre-stellar core. Comparison of the observations with the model predictions suggests that the emission from HCNH+ and HC3NH+ originates in the external layer where non-thermal desorption of other species was previously observed. The observed abundance of both ionic species ([HCNH+] ≃ 3 × 10-10 and [HC3NH+] ≃ [1.5 - 3.0] × 10-12, with respect to H2) cannot be reproduced at the same time by the chemical modelling within the error bars of the observations only. We discuss the possible reasons for the discrepancy and suggest that the current chemical models are not fully accurate or complete. However, the modelled abundances are within a factor of 3, consistent with the observations, considering a late stage of the evolution of the pre-stellar core, compatible with previous observations.

  5. Optrode for sensing hydrocarbons

    Science.gov (United States)

    Miller, Holly; Milanovich, Fred P.; Hirschfeld, Tomas B.; Miller, Fred S.

    1987-01-01

    A two-phase system employing the Fujiwara reaction is provided for the fluorometric detection of halogenated hydrocarbons. A fiber optic is utilized to illuminate a column of pyridine trapped in a capillary tube coaxially attached at one end to the illuminating end of the fiber optic. A strongly alkaline condition necessary for the reaction is maintained by providing a reservoir of alkali in contact with the column of pyridine, the surface of contact being adjacent to the illuminating end of the fiber optic. A semipermeable membrane caps the other end of the capillary tube, the membrane being preferentially permeable to the halogenated hydrocarbon and but preferentially impermeable to water and pyridine. As the halogenated hydrocarbon diffuses through the membrane and into the column of pyridine, fluorescent reaction products are formed. Light propagated by the fiber optic from a light source, excites the fluorescent products. Light from the fluorescence emission is also collected by the same fiber optic and transmitted to a detector. The intensity of the fluorescence gives a measure of the concentration of the halogenated hydrocarbons.

  6. Emission and operating performance of a biomethane tractor with dual fuel engine; Emissions- und Betriebsverhalten eines Biomethan-Traktors mit Zuendstrahlmotor

    Energy Technology Data Exchange (ETDEWEB)

    Mautner, Sebastian [Technologie- und Foerderzentrum (TFZ), Straubing (Germany); Emberger, Peter; Thuneke, Klaus; Remmele, Edgar

    2016-08-01

    The use of biomethane as fuel for agricultural machinery with dual fuel technology is contributing to climate protection and ensures safe fuel supply. So far, hardly any documented operational experiences are known. The aim of the project, funded by the Bavarian Ministry of Economic Affairs and Media, Energy and Technology, was to investigate practicability for daily use and the emission behaviour of a Valtra N101 prototype tractor (exhaust stage IIIA). The retrofitted dual-fuel technology of the former conventional diesel tractor simultaneously uses biomethane or natural gas and diesel as ignition fuel. During the field test over 590 working hours, the tractor showed overall high reliability. On average the operating range in dual-fuel mode with one complete filling of the gas tanks was about 11.5 hours. On the tractor test bench a significant improvement of the exhaust emissions could be observed, since the gas ECU had been optimized and changed by the manufacturer. For dual-fuel operation, nitrogen oxides (NO{sub x}) are lower, whereas carbon monoxide (CO), hydrocarbons (HC) and particulate matter emissions (PM) are higher compared to solely diesel operation. In particular, HC emissions exceed the proposed limiting value, submitted by the European Commission. This is due to incomplete gas combustion and insufficient conversion by the exhaust after-treatment-system (methane slip). A big potential for optimization is expected by adjusting the operating point-specific gasdiesel ratio and improving the exhaust gas aftertreatment system.

  7. Structure of dense molecular gas in TMC 1 from observations of three transitions of HC3N

    Science.gov (United States)

    Schloerb, F. P.; Snell, R. L.; Young, J. S.

    1983-01-01

    The Taurus dark cloud complex is a collection of many individual clouds scattered across approximately 50 pc. Within one of these, Heiles Cloud 2, is the dense condensation TMC 1. TMC 1 is one of the few sources in which some of the long carbon chain molecules are found. The present investigation is concerned with a mapping of the density structure in a narrow ridge of the TMC 1 structure. It is shown that the HC3N emission from the J = 5 to 4, J = 9 to 8, and J = 12 to 11 transitions is well matched by a narrow ridge of material at a single density of 50,000-100,000 per cu cm. There is evidence that the HC3N fractional abundance is variable along the ridge. Evidence is also found for the presence of subcondensations within this ridge from maps at individual velocities.

  8. Characterization of hydrocarbon utilizing fungi from hydrocarbon ...

    African Journals Online (AJOL)

    Prof. Ogunji

    hydrocarbon polluted sediments and water .... ecosystem may result in selective increase or decrease in microbial population (Okpokwasili ... been implicated in degradation of hydrocarbons such as crude oil, polyaromatic hydrocarbons and.

  9. HC-21C off-gas test procedure

    Energy Technology Data Exchange (ETDEWEB)

    Cunningham, L.T.

    1994-12-14

    The goal of this test plan is to determine the cause and location of water formation in the sludge stabilization off-gas system. The results should help determine what design improvements or processing steps will be implemented to prevent this phenomena from occurring in the future. This test procedure will include a series of tests to determine where and why liquid is condensing in the HC-21C furnace off-gas system. The tests will take a sequential, graded approach and may be concluded one the results have satisfactorily resolved the problem.

  10. HC-IPSAG and GC-IPSAG algorithm proposals

    DEFF Research Database (Denmark)

    Bǎdoi, C.-I.; Croitoru, V.; Prasad, N.

    2010-01-01

    networks by proposing two improved variants of IPSAG (IP Spectrum Aware Geographic routing algorithm). The destination geographical location is indirectly part of the routing metric that is proposed in IPSAG, and the main assumption on which IPSAG is based is that the source can always find the destination......, GCIPSAG, uses gateway nodes between clusters, without attempting to find where destination is located for inter-cluster routing. The second proposal, HC-IPSAG, is using an overlay network formed with cluster head nodes in order to locate the destination, and to inter-cluster route the packet....

  11. Structure-reactivity correlation of diesel soot and characterization of polycyclic aromatic hydrocarbons and carbonyls in biofuel emissions; Struktur-Reaktivitaets-Korrelation von Dieselruss und Charakterisierung von PAHs und Carbonylen im Abgas von Biokraftstoffen

    Energy Technology Data Exchange (ETDEWEB)

    Knauer, Markus

    2009-12-29

    This work reports on the determination of the structure-reactivity correlation of soot using Raman microscopy (RM) and temperature programmed oxidation (TPO), as well as on changes in the emission level of polycyclic aromatic hydrocarbons (PAH) and carbonyls at the combustion of biofuels. To characterize the reactivity of soot the combustion behaviour of model- and diesel soot has been determined by means of TPO in the presence of oxygen. In this context, spark-discharge soot and graphite powder were applied as model substances, and EURO VI and IV diesel soot as real-diesel soots. The structure of soot samples was investigated by RM and structural changes during the TPO were observed. In order to make a statement about the changes in PAH and carbonyl compound emissions during combustion of biofuels, samples were taken at different engine testbenches. Fossil fuel, biodiesel and vegetable oil were used during this study, as well as fuel mixtures with different biofuel fractions.

  12. The Infrared Spectra of Polycyclic Aromatic Hydrocarbons with Excess Peripheral H Atoms (H(sub n)-PAHs) and their Relation to the 3.4 and 6.9 Micrometer PAH Emission Features

    Science.gov (United States)

    Sandford, Scott A.; Bernstein, Max P.; Materese, Christopher K.

    2013-01-01

    A population of polycyclic aromatic hydrocarbons (PAHs) and related materials are thought to be responsible for the family of infrared emission features that are seen towards a wide variety of astrophysical environments. A potentially important subclass of these materials are polycyclic aromatic hydrocarbons whose edges contain excess H atoms (H(sub n)-PAHs). While it has been suggested that this type of compound may be present in the interstellar population, it has been difficult to properly assess this possibility because of a lack of suitable infrared laboratory spectra to assist with analysis of the astronomical data. We present the 4000-500 cm(exp -1) (2.5-20 micrometers) infrared spectra of 23 H(sub n)-PAHs and related molecules isolated in argon matrices, under conditions suitable for use in the interpretation of astronomical data. The spectra of molecules with mixed aromatic and aliphatic domains show unique characteristics that distinguish them from their fully aromatic PAH equivalents. We discuss the changes to the spectra of these types of molecules as they transition from fully aromatic to fully aliphatic forms. The implications for the interpretation of astronomical spectra are discussed with specific emphasis on the 3.4 and 6.9 micrometer features. Laboratory data is compared with emission spectra from IRAS 21282+5050, an object with normal PAH emission features, in addition to IRAS 22272+5435 and IRAS 0496+3429, two protoplanetary nebulae with abnormally large 3.4 micrometer features. We show that 'normal' PAH emission objects contain relatively few H(sub n)-PAHs in their emitter populations, but less evolved protoplanetary nebulae may contain significant abundances of these molecules.

  13. Reduction of Particulate Emissions in Turbine Engines Using the +100 Additive

    Science.gov (United States)

    2006-06-01

    element oscillating microbalance THC total unburned hydrocarbon UDRI University of Dayton Research Institute UHC unburned hydrocarbons UMR...all tests Primary Reduced gaseous pollutant emissions 20% reduction in CO, NOx and unburned hydrocarbons ( UHC ) emissions for all test conditions

  14. Apparatus for hydrocarbon extraction

    Science.gov (United States)

    Bohnert, George W.; Verhulst, Galen G.

    2013-03-19

    Systems and methods for hydrocarbon extraction from hydrocarbon-containing material. Such systems and methods relate to extracting hydrocarbon from hydrocarbon-containing material employing a non-aqueous extractant. Additionally, such systems and methods relate to recovering and reusing non-aqueous extractant employed for extracting hydrocarbon from hydrocarbon-containing material.

  15. Potato virus Y HC-Pro Reduces the ATPase Activity of NtMinD, Which Results in Enlarged Chloroplasts in HC-Pro Transgenic Tobacco

    Science.gov (United States)

    Tu, Yayi; Zhang, Zhenqian; Li, Daofeng; Li, Heng; Dong, Jiangli; Wang, Tao

    2015-01-01

    Potato virus Y (PVY) is an important plant virus and causes great losses every year. Viral infection often leads to abnormal chloroplasts. The first step of chloroplast division is the formation of FtsZ ring (Z-ring), and the placement of Z-ring is coordinated by the Min system in both bacteria and plants. In our lab, the helper-component proteinase (HC-Pro) of PVY was previously found to interact with the chloroplast division protein NtMinD through a yeast two-hybrid screening assay and a bimolecular fluorescence complementation (BiFC) assay in vivo. Here, we further investigated the biological significance of the NtMinD/HC-Pro interaction. We purified the NtMinD and HC-Pro proteins using a prokaryotic protein purification system and tested the effect of HC-Pro on the ATPase activity of NtMinD in vitro. We found that the ATPase activity of NtMinD was reduced in the presence of HC-Pro. In addition, another important chloroplast division related protein, NtMinE, was cloned from the cDNA of Nicotiana tabacum. And the NtMinD/NtMinE interaction site was mapped to the C-terminus of NtMinD, which overlaps the NtMinD/HC-Pro interaction site. Yeast three-hybrid assay demonstrated that HC-Pro competes with NtMinE for binding to NtMinD. HC-Pro was previously reported to accumulate in the chloroplasts of PVY-infected tobacco and we confirmed this result in our present work. The NtMinD/NtMinE interaction is very important in the regulation of chloroplast division. To demonstrate the influence of HC-Pro on chloroplast division, we generated HC-Pro transgenic tobacco with a transit peptide to retarget HC-Pro to the chloroplasts. The HC-Pro transgenic plants showed enlarged chloroplasts. Our present study demonstrated that the interaction between HC-Pro and NtMinD interfered with the function of NtMinD in chloroplast division, which results in enlarged chloroplasts in HC-Pro transgenic tobacco. The HC-Pro/NtMinD interaction may cause the formation of abnormal chloroplasts in PVY

  16. Potato virus Y HC-Pro Reduces the ATPase Activity of NtMinD, Which Results in Enlarged Chloroplasts in HC-Pro Transgenic Tobacco.

    Science.gov (United States)

    Tu, Yayi; Zhang, Zhenqian; Li, Daofeng; Li, Heng; Dong, Jiangli; Wang, Tao

    2015-01-01

    Potato virus Y (PVY) is an important plant virus and causes great losses every year. Viral infection often leads to abnormal chloroplasts. The first step of chloroplast division is the formation of FtsZ ring (Z-ring), and the placement of Z-ring is coordinated by the Min system in both bacteria and plants. In our lab, the helper-component proteinase (HC-Pro) of PVY was previously found to interact with the chloroplast division protein NtMinD through a yeast two-hybrid screening assay and a bimolecular fluorescence complementation (BiFC) assay in vivo. Here, we further investigated the biological significance of the NtMinD/HC-Pro interaction. We purified the NtMinD and HC-Pro proteins using a prokaryotic protein purification system and tested the effect of HC-Pro on the ATPase activity of NtMinD in vitro. We found that the ATPase activity of NtMinD was reduced in the presence of HC-Pro. In addition, another important chloroplast division related protein, NtMinE, was cloned from the cDNA of Nicotiana tabacum. And the NtMinD/NtMinE interaction site was mapped to the C-terminus of NtMinD, which overlaps the NtMinD/HC-Pro interaction site. Yeast three-hybrid assay demonstrated that HC-Pro competes with NtMinE for binding to NtMinD. HC-Pro was previously reported to accumulate in the chloroplasts of PVY-infected tobacco and we confirmed this result in our present work. The NtMinD/NtMinE interaction is very important in the regulation of chloroplast division. To demonstrate the influence of HC-Pro on chloroplast division, we generated HC-Pro transgenic tobacco with a transit peptide to retarget HC-Pro to the chloroplasts. The HC-Pro transgenic plants showed enlarged chloroplasts. Our present study demonstrated that the interaction between HC-Pro and NtMinD interfered with the function of NtMinD in chloroplast division, which results in enlarged chloroplasts in HC-Pro transgenic tobacco. The HC-Pro/NtMinD interaction may cause the formation of abnormal chloroplasts in PVY

  17. IDI diesel engine performance and exhaust emission analysis using biodiesel with an artificial neural network (ANN

    Directory of Open Access Journals (Sweden)

    K. Prasada Rao

    2017-09-01

    Full Text Available Biodiesel is receiving increasing attention each passing day because of its fuel properties and compatibility. This study investigates the performance and emission characteristics of single cylinder four stroke indirect diesel injection (IDI engine fueled with Rice Bran Methyl Ester (RBME with Isopropanol additive. The investigation is done through a combination of experimental data analysis and artificial neural network (ANN modeling. The study used IDI engine experimental data to evaluate nine engine performance and emission parameters including Exhaust Gas Temperature (E.G.T, Brake Specific Fuel Consumption (BSFC, Brake Thermal Efficiency (B.The and various emissions like Hydrocarbons (HC, Carbon monoxide (CO, Carbon dioxide (CO2, Oxygen (O2, Nitrogen oxides (NOX and smoke. For the ANN modeling standard back propagation algorithm was found to be the optimum choice for training the model. A multi-layer perception (MLP network was used for non-linear mapping between the input and output parameters. It was found that ANN was able to predict the engine performance and exhaust emissions with a correlation coefficient of 0.995, 0.980, 0.999, 0.985, 0.999, 0.999, 0.980, 0.999, and 0.999 for E.G.T, BSFC, B.The, HC, O2, CO2, CO, NOX, smoke respectively.

  18. Effects of ethylene glycol ethers on diesel fuel properties and emissions in a diesel engine

    Energy Technology Data Exchange (ETDEWEB)

    Gomez-Cuenca, F.; Gomez-Marin, M. [Compania Logistica de Hidrocarburos (CLH), Central Laboratory, Mendez Alvaro 44, 28045 Madrid (Spain); Folgueras-Diaz, M.B., E-mail: belenfd@uniovi.es [Department of Energy, University of Oviedo, Independencia 13, 33004 Oviedo (Spain)

    2011-08-15

    Highlights: {yields} Effect of ethylene glycol ethers on diesel fuel properties. {yields} Effect of ethylene glycol ethers on diesel engine specific consumption and emissions. {yields} Blends with {<=}4 wt.% of oxygen do not change substantially diesel fuel quality. {yields} Blends with 1 and 2.5 wt.% of oxygen reduce CO and HC emissions, but not smoke. - Abstract: The effect of ethylene glycol ethers on both the diesel fuel characteristics and the exhaust emissions (CO, NO{sub x}, smoke and hydrocarbons) from a diesel engine was studied. The ethers used were monoethylene glycol ethyl ether (EGEE), monoethylene glycol butyl ether (EGBE), diethylene glycol ethyl ether (DEGEE). The above effect was studied in two forms: first by determining the modification of base diesel fuel properties by using blends with oxygen concentration around 4 wt.%, and second by determining the emission reductions for blends with low oxygen content (1 wt.%) and with 2.5 wt.% of oxygen content. The addition of DEGEE enhances base diesel fuel cetane number, but EGEE and EGBE decrease it. For concentrations of {>=}4 wt.% of oxygen, EGEE and diesel fuel can show immiscibility problems at low temperatures ({<=}0 {sup o}C). Also, every oxygenated compound, according to its boiling point, modifies the distillation curve at low temperatures and the distillate percentage increases. These compounds have a positive effect on diesel fuel lubricity, and slightly decrease its viscosity. Blends with 1 and 2.5 wt.% oxygen concentrations were used in order to determine their influence on emissions at both full and medium loads and different engine speeds. Generally, all compounds help to reduce CO, and hydrocarbon emissions, but not smoke. The best results were obtained for blends with 2.5 wt.% of oxygen. At this concentration, the additive efficiency in decreasing order was EGEE > DEGEE > EGBE for CO emissions and DGEE > EGEE > EGBE for hydrocarbon emissions. For NO{sub x}, both its behaviour and the

  19. Detection of radiation-induced hydrocarbons in baked sponged cake prepared with irradiated liquid egg

    Science.gov (United States)

    Schulzki, G.; Spiegelberg, A.; Bögl, K. W.; Schreiber, G. A.

    1995-02-01

    For identification of irradiated food, radiation-induced volatile hydrocarbons (HC) are determined by gas chromatography in the non-polar fraction of fat. However, in complex food matrices the detection is often disturbed by fat-associated compounds. On-line coupling of high performance liquid chromatography (LC) and gas chromatography (GC) is very efficient to remove such compounds from the HC fraction. The high sensitivity of this fast and efficient technique is demonstrated by the example of detection of radiation-induced HC in fat isolated from baked sponge cake which had been prepared with irradiated liquid egg.

  20. Detection of radiation-induced hydrocarbons in baked sponge cake prepared with irradiated liquid egg

    Energy Technology Data Exchange (ETDEWEB)

    Schulzki, G.; Spiegelberg, A.; Boegl, K.W.; Schreiber, G.A. [Federal Institute for Health Protection of Consumers and Veterinary Medicine, Berlin (Germany)

    1995-10-01

    For identification of irradiated food, radiation-induced volatile hydrocarbons (HC) are determined by gas chromatography in the non-polar fraction of fat. However, in complex food matrices the detection is often disturbed by fat-associated compounds. On-line coupling of high performance liquid chromatography (LC) and gas chromatography (GC) is very efficient to remove such compounds from the HC fraction. The high sensitivity of this fast and efficient technique is demonstrated by the example of detection of radiation-induced HC in fat isolated from baked sponge cake which had been prepared with irradiated liquid egg. (Author).

  1. EFFECT OF GASOLINE - ETHANOL BLENDS ON PERFORMANCE AND EMISSION CHARACTERISTICS OF A SINGLE CYLINDER AIR COOLED MOTOR BIKE SI ENGINE

    Directory of Open Access Journals (Sweden)

    A. SAMUEL RAJA

    2015-12-01

    Full Text Available This paper investigates the effect of using gasoline-ethanol (GE blends on performance and exhaust emission of a four stroke 150 cc single cylinder air cooled spark ignition (SI engine, without any modifications. Experiments were conducted at part load and different engine speeds ranging from 3000 to 5000 rpm, without and with catalytic converter. Ethanol content was varied from 5 percentage to 20 percentage by volume and four different blends (E5, E10, E15 and E20 were tested. Fuel consumption, engine speed, air fuel ratio, exhaust gas temperature and exhaust emissions were measured during each experiment. Brake thermal efficiency (ηb,th, volumetric efficiency (ηvol, brake specific fuel consumption (BSFC and excess air factor were calculated for each test run. Brake specific fuel consumption, volumetric efficiency and excess air factor increased with ethanol percentage in the blend. Carbon monoxide (CO, hydrocarbon (HC and oxides of nitrogen (NOx emissions decreased with blends.

  2. Emissions from Road Vehicles Fuelled by Fischer Tropsch Based Diesel and Gasoline

    Energy Technology Data Exchange (ETDEWEB)

    Larsen, U.; Lundorf, P.; Ivarsson, A.; Schramm, J. [Technical University of Denmark (Denmark); Rehnlund, B. [Atrax Energi AB (Sweden); Blinge, M. [The Swedish Transport Institute (Sweden)

    2006-11-15

    The described results were carried out under the umbrella of IEA Advanced Motor Fuels Agreement. The purpose was to evaluate the emissions of carbon monoxide (CO), unburned hydrocarbons (HC), nitrogen oxides (NOx), particulate matter (PM) and polycyclic aromatic hydrocarbons (PAH) from vehicles fuelled by Fischer Tropsch (FT) based diesel and gasoline fuel, compared to the emissions from ordinary diesel and gasoline. The comparison for diesel fuels was based on a literature review, whereas the gasoline comparison had to be based on our own experiments, since almost no references were found in this field. In this context measurement according to the Federal Test Procedure (FTP) and the New European Driving Cycle (NEDC) were carried out on a chassis dynamometer with a directly injected gasoline vehicle. Experiments were carried out with a reference fuel, a fuel based 70% on FT and an alkylate fuel (Aspen), which was supposed to be very similar, in many ways, to FT fuel. FT based diesel generally showed good emission performance, whereas the FT based gasoline not necessary lead to lower emissions. On the other hand, the Aspen fuel did show many advantages for the emissions from the gasoline vehicle.

  3. Emissions from Road Vehicles Fuelled by Fischer Tropsch Based Diesel and Gasoline

    Energy Technology Data Exchange (ETDEWEB)

    Larsen, U.; Lundorf, P.; Ivarsson, A.; Schramm, J. [Technical University of Denmark (Denmark); Rehnlund, B. [Atrax Energi AB (Sweden); Blinge, M. [The Swedish Transport Institute (Sweden)

    2006-11-15

    The described results were carried out under the umbrella of IEA Advanced Motor Fuels Agreement. The purpose was to evaluate the emissions of carbon monoxide (CO), unburned hydrocarbons (HC), nitrogen oxides (NOx), particulate matter (PM) and polycyclic aromatic hydrocarbons (PAH) from vehicles fuelled by Fischer Tropsch (FT) based diesel and gasoline fuel, compared to the emissions from ordinary diesel and gasoline. The comparison for diesel fuels was based on a literature review, whereas the gasoline comparison had to be based on our own experiments, since almost no references were found in this field. In this context measurement according to the Federal Test Procedure (FTP) and the New European Driving Cycle (NEDC) were carried out on a chassis dynamometer with a directly injected gasoline vehicle. Experiments were carried out with a reference fuel, a fuel based 70% on FT and an alkylate fuel (Aspen), which was supposed to be very similar, in many ways, to FT fuel. FT based diesel generally showed good emission performance, whereas the FT based gasoline not necessary lead to lower emissions. On the other hand, the Aspen fuel did show many advantages for the emissions from the gasoline vehicle.

  4. Photophysics of the Red Chromophore of HcRed: Evidence for Cis-Trans Isomerization and Protonation-State Changes

    Energy Technology Data Exchange (ETDEWEB)

    Cotlet, M.; Mudalige, K.; Habuchi, S.; Goodwin, P.M.; Pai, R.K.; De Schryver, F.

    2010-03-15

    HcRed is a dimeric intrinsically fluorescent protein with origins in the sea anemone Heteractis crispa. This protein exhibits deep red absorption and emission properties. Using a combination of ensemble and single molecule methods and by varying environmental parameters such as temperature and pH, we found spectroscopic evidence for the presence of two ground state conformers, trans and cis chromophores that are in thermal equilibrium and that follow different excited-state pathways upon exposure to light. The photocycle of HcRed appears to be a combination of both kindling proteins and bright emitting GFP/GFP-like proteins: the trans chromophore undergoes light driven isomerization followed by radiative relaxation with a fluorescence lifetime of 0.5 ns. The cis chromophore exhibits a photocycle similar to bright GFPs and GFP-like proteins such as enhanced GFP, enhanced YFP or DsRed, with radiative relaxation with a fluorescence lifetime of 1.5 ns, singlet-triplet deactivation on a microsecond time scale and solvent controlled protonation/deprotonation in tens of microseconds. Using single molecule spectroscopy, we identify trans and cis conformers at the level of individual moieties and show that it is possible that the two conformers can coexist in a single protein due to the dimeric nature of HcRed.

  5. Wall quench and flammability limit effects on exhaust hydrocarbon emissions. Final technical report, Phase 5: 1 August 1980-30 September 1980

    Energy Technology Data Exchange (ETDEWEB)

    Fendell, F.

    1980-10-01

    Progress is reported in a project concerned with simple modeling and laboratory experiments to elucidate the mechanisms whereby trace amounts of unburned hydrocarbons may persist after the combustion event in Otto-cycle-type internal-combustion-engine cylinders, and the fate of these residual hydrocarbons during the power-stroke and exhaust-event portions of the cycle. The motivation for the research is that a highly fuel-lean fast-burn design for the spark-ignition homogeneous-charge, four-stroke engine may permit exceptionally fuel-efficient operation of this highly driveable, relatively well-understood automotive engine. Work during this period concentrated on the mathematical modelling of wall quenching and turbulent flame propagation. (LCL)

  6. Effects of fractal grid on emissions in burner combustion by using fuel-water-air premix injector derived from biodiesel crude palm oil (CPO base

    Directory of Open Access Journals (Sweden)

    Suardi Mirnah

    2017-01-01

    Full Text Available The alternative fuel is attracted good attention from worldwide especially for renewable and prevention energy such as biodiesel. Biodiesel is one of the hydrocarbon fuels and it has potential for external combustion. As one of the different solutions to these problems, rapid mixing of biodiesel-water-air technique is one of the most significant approaches to improve the combustion and reduce the emissions. The gas emission can be reduced by two methods. First is by improving an injector with fractal and the other is by using a biodiesel-water mixture as an alternative fuel. Mixing of water with fuel in the combustion process is a low cost and effective way. This research used biodiesel Crude Palm Oil (CPO as fuels in which blended with diesel. This study investigated the effects of water content and equivalence ratio on emissions with the rapid mixing injector. Fuels used are diesel, CPO5, CPO10 and CPO15 and the exhausts gaseous tested are CO, CO2, HC and NOX. The gas emissions processes are tested by using the gas analyzer. In this research, water premix of percentage up to 15vol% and blending biodiesel ratio was varied from 5vom% - 15vol%. The result shows that increasing of water content will effected decrement of CO, CO2 and HC emissions but increasing the NOX emissions.

  7. HC-21C off-gas test procedure. Revision 1

    Energy Technology Data Exchange (ETDEWEB)

    Cunningham, L.T.

    1995-02-02

    Stabilization of plutonium bearing scrap material occurs in furnaces, FUR-21C-1 and FUR-21C-2, located in glovebox HC-21C. During previous testing and processing operations, water has been observed forming in the off-gas rotameters, FI-21C-1 and FI-21C-2. The off-gas is filtered through a 2 micron ceramic filter, F-21C-1 or F-21C-2, before discharge into the 26 inch vacuum system. The goal of this test plan is to determine the cause and location of water formation in the sludge stabilization off-gas system. The results should help determine what design improvements or processing steps will be implemented to prevent this phenomena from occurring in the future.

  8. Monetarism and fixed rules in H.C. Simons

    Directory of Open Access Journals (Sweden)

    M. TONVERONACHI

    2013-12-01

    Full Text Available The comparison of H.C. Simons’ theories to those of Friedman and Keynes has resulted in confining the former to some of the issues debated in the recent controversies between the monetarist and the Keynesian schools. The present article demonstrates that a more balanced analysis of Simons’ theories can modify some of the outcomes obtained. In particular, the author gives less importance to differences in monetary theory while placing more weight on those of a pre-analytic and general theoretical nature. This distinction is of use when it comes to a question which drives a deep gulf between modern monetarists and Keynesians - that of the choice between fixed rules and discretionary policies.

  9. Cold-start emissions of modern passenger cars at different low ambient temperatures and their evolution over vehicle legislation categories

    Science.gov (United States)

    Weilenmann, Martin; Favez, Jean-Yves; Alvarez, Robert

    The emissions of modern gasoline and diesel passenger cars are reduced by catalysts except in cold-starting. Since catalysts require a certain temperature (typically above 300 °C) to work to full efficiency, emissions are significantly higher during the warm-up phase of the car. The duration of this period and the emissions produced depend on the ambient temperature as well as on the initial temperature of the car's propulsion systems. The additional emissions during a warm-up phase, known as "cold-start extra emissions" (CSEEs) for emission inventory modelling, are mostly assessed by emission measurements at an ambient temperature of 23 °C. However, in many European countries average ambient temperatures are below 23 °C. This necessitates emission measurements at lower temperatures in order to model and assess cold-start emissions for real-world temperature conditions. This paper investigates the influence of regulated pollutants and CO 2 emissions of recent gasoline and diesel car models (Euro-4 legislation) at different ambient temperatures, 23, -7 and -20 °C. We present a survey and model of the evolution of cold-start emissions as a function of different car generations (pre-Euro-1 to Euro-4 legislations). In addition the contribution of CSEEs to total fleet running emissions is shown to highlight their increasing importance. For gasoline cars, it turns out that in average real-world driving the majority of the CO (carbon monoxide) and HC (hydrocarbon) total emissions are due to cold-start extra emissions. Moreover, the cold-start emissions increase considerably at lower ambient temperatures. In contrast, cold-start emissions of diesel cars are significantly lower than those of gasoline cars. Furthermore, the transition from Euro-3 to Euro-4 gasoline vehicles shows a trend for a smaller decline for cold-start extra emissions than for legislative limits. Particle and NO x emission of cold-starts are less significant.

  10. Varroa destructor changes its cuticular hydrocarbons to mimic new hosts.

    Science.gov (United States)

    Le Conte, Y; Huang, Z Y; Roux, M; Zeng, Z J; Christidès, J-P; Bagnères, A-G

    2015-06-01

    Varroa destructor (Vd) is a honeybee ectoparasite. Its original host is the Asian honeybee, Apis cerana, but it has also become a severe, global threat to the European honeybee, Apis mellifera. Previous studies have shown that Varroa can mimic a host's cuticular hydrocarbons (HC), enabling the parasite to escape the hygienic behaviour of the host honeybees. By transferring mites between the two honeybee species, we further demonstrate that Vd is able to mimic the cuticular HC of a novel host species when artificially transferred to this new host. Mites originally from A. cerana are more efficient than mites from A. mellifera in mimicking HC of both A. cerana and A. mellifera. This remarkable adaptability may explain their relatively recent host-shift from A. cerana to A. mellifera.

  11. On-board measurements of gaseous pollutant emission characteristics under real driving conditions from light-duty diesel vehicles in Chinese cities.

    Science.gov (United States)

    Wang, Gang; Cheng, Shuiyuan; Lang, Jianlei; Li, Song; Tian, Liang

    2016-08-01

    A total of 15 light-duty diesel vehicles (LDDVs) were tested with the goal of understanding the emission factors of real-world vehicles by conducting on-board emission measurements. The emission characteristics of hydrocarbons (HC) and nitrogen oxides (NOx) at different speeds, chemical species profiles and ozone formation potential (OFP) of volatile organic compounds (VOCs) emitted from diesel vehicles with different emission standards were analyzed. The results demonstrated that emission reductions of HC and NOx had been achieved as the control technology became more rigorous from Stage I to Stage IV. It was also found that the HC and NOx emissions and percentage of O2 dropped with the increase of speed, while the percentage of CO2 increased. The abundance of alkanes was significantly higher in diesel vehicle emissions, approximately accounting for 41.1%-45.2%, followed by aromatics and alkenes. The most abundant species were propene, ethane, n-decane, n-undecane, and n-dodecane. The maximum incremental reactivity (MIR) method was adopted to evaluate the contributions of individual VOCs to OFP. The results indicated that the largest contributors to O3 production were alkenes and aromatics, which accounted for 87.7%-91.5%. Propene, ethene, 1,2,4-trimethylbenzene, 1-butene, and 1,2,3-trimethylbenzene were the top five VOC species based on their OFP, and accounted for 54.0%-64.8% of the total OFP. The threshold dilution factor was applied to analyze the possibility of VOC stench pollution. The majority of stench components emitted from vehicle exhaust were aromatics, especially p-diethylbenzene, propylbenzene, m-ethyltoluene, and p-ethyltoluene.

  12. Relative contribution of oxygenated hydrocarbons to the total biogenic VOC emissions of selected mid-European agricultural and natural plant species

    Science.gov (United States)

    König, Georg; Brunda, Monika; Puxbaum, Hans; Hewitt, C. Nicholas; Duckham, S. Craig; Rudolph, Jochen

    Emission rates of more than 50 individual VOCs were determined for eight plant species and three different types of grass land typical for natural deciduous and agricultural vegetation in Austria. In addition to the emissions of isoprene and monoterpenes, 33 biogenic oxygenated volatile organic compounds (BOVOCs) were detected. Of these, 2-methyl-l-propanol, 1-butanal, 2-butanal, 1-pentanol, 3-pentanol, 1-hexanol, 6-methyl-5-hepten-2-one, butanal and ethylhexylacetate were observed for the first time as plant emissions. In terms of prevalence of one of the groups of emitted VOCs (isoprene, terpenes, BOVOCs) the grain plants wheat and rye, grape, oilseed rape and the decidous trees hombeam and birch could be classified as "BOVOC"-emitters. For the grass plots examined, BOVOCs and terpenes appear to be of equal importance. The emission rates of the total assigned organic plant emissions ranged from 0.01 μ g -1 h -1 for wheat to 0.8 μg g -1 h -1 for oak (based on dry leaf weight). Intercomparison with available data from other studies show that our emission rates are rather at the lower end of reported ranges. The influence of the stage of growth was examined for rye, rape (comparing emissions of blossoming and nonblossoming plants) and for grape (with and without fruit). Emission rate differences for different stages of growth varied from nondetectable for blossoming and nonblossoming rye to a factor of six for the grape with fruits vs grape without fruits (emission rate based on dry leaf weight). The major decidous tree in Austria (beech) is a terpene emitter, with the contribution of BOVOCs below 5% of the total assigned emissions of 0.2 μg g -1 h -1 for the investigations of 20°C.

  13. A Commercial Aircraft Fuel Burn and Emissions Inventory for 2005–2011

    Directory of Open Access Journals (Sweden)

    Donata K. Wasiuk

    2016-06-01

    Full Text Available The commercial aircraft fuel burn and emission estimates of CO2, CO, H2O, hydrocarbons, NOx and SOx for 2005–2011 are given as the 4-D Aircraft Fuel Burn and Emissions Inventory. On average, the annual fuel burn and emissions of CO2, H2O, NOx, and SOx increased by 2%–3% for 2005–2011, however, annual CO and HC emissions decreased by 1.6% and 8.7%, respectively because of improving combustion efficiency in recent aircraft. Approximately 90% of the global annual aircraft NOx emissions were emitted in the NH between 2005 and 2011. Air traffic within the three main industrialised regions of the NH (Asia, Europe, and North America alone accounted for 80% of the global number of departures, resulting in 50% and 45% of the global aircraft CO2 and NOx emissions, respectively, during 2005–2011. The current Asian fleet appears to impact our climate strongly (in terms of CO2 and NOx when compared with the European and North American fleet. The changes in the geographical distribution and a gradual shift of the global aircraft NOx emissions as well as a subtle but steady change in regional emissions trends are shown in particular comparatively rising growth rates between 0 and 30°N and decreasing levels between 30 and 60°N.

  14. The discovery of a new infrared emission feature at 1905 wavenumbers (5.25 microns) in the spectrum of BD +30 degrees 3639 and its relation to the polycyclic aromatic hydrocarbon model

    Science.gov (United States)

    Allamandola, L. J.; Bregman, J. D.; Sandford, S. A.; Tielens, A. G.; Witteborn, F. C.; Wooden, D. H.; Rank, D.

    1989-01-01

    We have discovered a new IR emission feature at 1905 cm-1 (5.25 microns) in the spectrum of BD +30 degrees 3639. This feature joins the family of well-known IR emission features at 3040, 2940, 1750, 1610, "1310," 1160, and 890 cm-1 (3.3, 3.4, 5.7, 6.2, "7.7," 8.6, and 11.2 microns). The origin of this new feature is discussed and it is assigned to an overtone or combination band involving C-H bending modes of polycyclic aromatic hydrocarbons (PAHs). Laboratory work suggests that spectral studies of the 2000-1650 cm-1 (5.0-6.1 microns) region may be very useful in elucidating the molecular structure of interstellar PAHs. The new feature, in conjunction with other recently discovered spectral structure, suggests that the narrow IR emission features originate in PAH molecules rather than large carbon grains. Larger species are likely to be the source of the broad underlying "plateaus" seen in many of the spectra.

  15. Heuristic Scheme for Home Circuit Grouping andWavelength Assignment in LOBS-HC Networks

    Science.gov (United States)

    Yang, Ximin; Yi, Bo; Tang, Wan; Li, Jingcong

    2014-09-01

    Grouping the Home Circuits (HCs) with the same source is a critical issue of Labeled Optical Burst Switching with Home Circuit (LOBS-HC). To maximize the wavelength utilization in LOBS-HC ring networks, an HC grouping and wavelength assignment scheme, called Longest Path Matching and Graph Coloring (LPMGC), is proposed. LPMGC consists of two phases: grouping and wavelength assignment. First, a heuristic algorithm, named Longest Path Matching (LPM), is proposed to group the HCs according to the longest common path matching between HCs and to make each group as large as possible. And then, Graph Coloring (GC) is introduced to assign wavelengths for HC groups. The numerical results show that the proposed scheme performances better than Complementary HC Assignment (CHA) and some other heuristics in both unidirectional and bidirectional LOBS-HC ring networks in terms of wavelength utilization.

  16. Bimolecular reactions of activated species: An analysis of problematic HC(O)C(O) chemistry

    Science.gov (United States)

    Shannon, Robin J.; Robertson, Struan H.; Blitz, Mark A.; Seakins, Paul W.

    2016-09-01

    Experimental studies have demonstrated the importance of non-thermal bimolecular association chemistry. Recently a fully reversible method for incorporating any number of such non-thermal reactions into a single master equation has been developed (Green and Robertson, 2014) [10]. Using this methodology experimental results for the system: (1) (CHO)2 + OH → HC(O)C(O) + H2O, (2) HC(O)C(O) → HCO + CO, (3) HC(O)C(O) + O2 → OH + CO + CO2, are modeled, reproducing the temperature and pressure dependence of the OH yield. An issue remains as to how to model energy partition into HC(O)C(O).

  17. Measurements of emission rates of hydrocarbons from sunflower as a function of temperature, light intensity and stress (ozone levels); Bestimmung von Emissionsraten pflanzlicher Kohlenwasserstoffe bei Sonnenblumen in Abhaengigkeit von Temperatur, Lichtintensitaet und Stress, insbesondere von der Belastung mit Ozon

    Energy Technology Data Exchange (ETDEWEB)

    Schuh, G.; Wildt, J.; Kley, D.

    1996-08-01

    The emission rates of isoprene, mono- and sesquiterpenes from sunflower (Helianthus annuus L. cv. giganteus) were determined in an environmental chamber, a continuously stirred tank reactor. {alpha}-pinene, {beta}-caryophyllene and two oxygenated compounds were emitted. The emission rates of all terpenes increased exponentially with temperature. Substance specific differences of the rate of increase of the emission rates were observed. For all substances the dependence of their emission rates on temperature increased with increasing light intensity. Increasing lightflux resulted in an increase of the emission rates for all substances. The raise of emission rates with lightflux was dependent on temperature and increased with increasing temperature. During periods without plant stress the emission rates exhibited a good correlation with the rate of transpiration as well as with the rate of net photosynthesis. Sunflowers emitted higher amounts of terpenes when they were stressed by mechanical, wounding and ozone treatment as well as nutrient- or water deficiency. The emission rates increased by a factor of 5-300. Exposure with ozone had an effect on hydrocarbon emission rates with a delay-time. 3-4 h after exposure with 25-120 ppb ozone the emission rates increased by factor of 5-100. This increase was only observed on the first day of exposure. Nutrient deficiency resulted in an increase of emission rates by a factor of 10-300. In situations of mechanical, wounding and ozone stress, substance specific changes in the emission spectrum were observed. A model was developed to explain the observed phenomena. The main pathway of ozone loss in the chamber is caused by the uptake through the stomata of the plants. However, up to 50% of the ozone loss must be explained by other processes indirectly caused by the plants. (orig./MG) [Deutsch] In Laborversuchen wurden Emissionsraten biogener Kohlenwasserstoffe von Sonnenblumen gemessen. Die groessten Emissionsraten wiesen die

  18. Bioethanol-gasoline fuel blends: exhaust emissions and morphological characterization of particulate from a moped engine.

    Science.gov (United States)

    Seggiani, Maurizia; Prati, M Vittoria; Costagliola, M Antonietta; Puccini, Monica; Vitolo, Sandra

    2012-08-01

    This study was aimed at evaluating the effects of gasoline-ethanol blends on the exhaust emissions in a catalyst-equipped four-stroke moped engine. The ethanol was blended with unleaded gasoline in at percentages (10, 15, and 20% v/v). The regulated pollutants and the particulate matter emissions were evaluated over the European ECE R47 driving cycle on the chassis dynamometer bench. Particulate matter was characterized in terms of total mass collected on filters and total number ofparticles in the range 7 nm-10 microm measured by electrical low-pressure impactor (ELPI). In addition, particle-phase polycyclic aromatic hydrocarbons (PAHs) emissions were evaluated to assess the health impact of the emitted particulate. Finally, an accurate morphological analysis was performed on the particulate by high-resolution transmission electron microscope (TEM) equipped with a digital image-processing/data-acquisition system. In general, CO emission reductions of 60-70% were obtained with 15 and 20% v/v ethanol blends, while the ethanol use did not reduce hydrocarbon (HC) and NOx emissions. No evident effect of ethanol on the particulate mass emissions and associated PAHs emissions was observed. Twenty-one PAHs were quantified in the particulate phase with emissions ranging from 26 to 35 microg/km and benzo[a]pyrene equivalent (BaPeq) emission factors from 2.2 to 4.1 microg/km. Both particulate matter and associated PAHs with higher carcinogenic risk were mainly emitted in the submicrometer size range (<0.1 microm). On the basis of the TEM observations, no relevant effect of the ethanol use on the particulate morphology was evidenced, showing aggregates composed ofprimary particles with mean diameters in the range 17.5-32.5 nm.

  19. The HC-LAC: a Platform for Modeling Hydrology and Climate Change in Latin America and the Caribbean

    Science.gov (United States)

    Moreda, F.; Wyatt, A.; Bruhn, M.; Wheaton, W.; Miralles-Wilhelm, F.; Muñoz-Castillo, R.; Rineer, J.

    2013-05-01

    emissions scenario with two general circulation models: the UKMO Hadley CM3 (used frequently in Argentina) and the CSIRO Mk3 (the "dry" scenario used by World Bank) for the period 2012-2060. The three stream flow time series were used to calculate unmet water demand for urban water supply and irrigation, taking into account various measures to adopt to climate change. The HC-LAC was also used to generate a complete surface flow database for the Rio Grande basin, which is proving useful for analysis of a variety of current and future water resource management issues by the local governmental agencies.

  20. THE INFRARED SPECTRA OF POLYCYCLIC AROMATIC HYDROCARBONS WITH EXCESS PERIPHERAL H ATOMS (H {sub n} -PAHs) AND THEIR RELATION TO THE 3.4 AND 6.9 {mu}m PAH EMISSION FEATURES

    Energy Technology Data Exchange (ETDEWEB)

    Sandford, Scott A.; Bernstein, Max P. [NASA-Ames Research Center, Mail Stop 245-6, Moffett Field, CA 94035-1000 (United States); Materese, Christopher K., E-mail: Scott.A.Sandford@nasa.gov [SETI Institute, 189 Bernardo Avenue, Suite 100, Mountain View, CA 94043 (United States)

    2013-03-01

    Polycyclic aromatic hydrocarbons (PAHs) are likely responsible for the family of infrared emission features seen in a wide variety of astrophysical environments. A potentially important subclass of these materials are PAHs whose edges contain excess H atoms (H {sub n} -PAHs). This type of compound may be present in space, but it has been difficult to assess this possibility because of a lack of suitable laboratory spectra to assist with analysis of astronomical data. We present 4000-500 cm{sup -1} (2.5-20 {mu}m) infrared spectra of 23 H {sub n} -PAHs and related molecules isolated in argon matrices under conditions suitable for interpretation of astronomical data. Spectra of molecules with mixed aromatic and aliphatic domains show characteristics that distinguish them from fully aromatic PAH equivalents. Two major changes occur as PAHs become more hydrogenated: (1) aromatic C-H stretching bands near 3.3 {mu}m weaken and are replaced with stronger aliphatic bands near 3.4 {mu}m, and (2) aromatic C-H out-of-plane bending mode bands in the 11-15 {mu}m region shift and weaken concurrent with growth of a strong aliphatic -CH{sub 2}- deformation mode near 6.9 {mu}m. Implications for interpreting astronomical spectra are discussed with emphasis on the 3.4 and 6.9 {mu}m features. Laboratory data is compared with emission spectra from IRAS 21282+5050, an object with normal PAH emission features, and IRAS 22272+5435 and IRAS 0496+3429, two protoplanetary nebulae with abnormally large 3.4 {mu}m features. We show that 'normal' PAH emission objects contain relatively few H {sub n} -PAHs in their emitter populations, but less evolved protoplanetary nebulae may contain significant abundances of these molecules.

  1. The hydrocarbon sphere

    Energy Technology Data Exchange (ETDEWEB)

    Mandev, P.

    1984-01-01

    The hydrocarbon sphere is understood to be the area in which hydrocarbon compounds are available. It is believed that the lower boundary on the hydrocarbon sphere is most probably located at a depth where the predominant temperatures aid in the destruction of hydrocarbons (300 to 400 degrees centigrade). The upper limit on the hydrocarbon sphere obviously occurs at the earth's surface, where hydrocarbons oxidize to H20 and CO2. Within these ranges, the occurrence of the hydrocarbon sphere may vary from the first few hundred meters to 15 kilometers or more. The hydrocarbon sphere is divided into the external (mantle) sphere in which the primary gas, oil and solid hydrocarbon fields are located, and the internal (metamorphic) sphere containing primarily noncommercial accumulations of hydrocarbon gases and solid carbon containing compounds (anthraxilite, shungite, graphite, etc.) based on the nature and scale of hydrocarbon compound concentrations (natural gas, oil, maltha, asphalt, asphaltite, etc.).

  2. Comparison of Practical Investigations for CO Emissions Emitted From Single Cylinder S. I. Engine Fueled With Different Kinds of Hydrocarbon Fuels and Hydrogen

    Directory of Open Access Journals (Sweden)

    Khalil Ibrahim Abaas

    2011-01-01

    Full Text Available Liquefied petroleum gas (LPG, Natural gas (NG and hydrogen were all used to operate spark ignition internal combustion engine Ricardo E6. A comparison of CO emissions emitted from each case, with emissions emitted from engine fueled with gasoline as a fuel is conducted.The study was accomplished when engine operated at HUCR for gasoline n(8:1, was compared with its operation at HUCR for each fuel. Compression ratio, equivalence ratio and spark timing were studied at constant speed 1500 rpm.CO concentrations were little at lean ratios; it appeared to be effected a little with equivalence ratio in this side, at rich side its values became higher, and it appeared to be effected by equivalence ratio highly, the results showed that CO emissions resulted from gasoline engine were higher than that resulted from using LPG and NG all the time; while hydrogen engine emitted extremely low CO concentrations.

  3. Real-world operation conditions and on-road emissions of Beijing diesel buses measured by using portable emission measurement system and electric low-pressure impactor.

    Science.gov (United States)

    Liu, Zhihua; Ge, Yunshan; Johnson, Kent C; Shah, Asad Naeem; Tan, Jianwei; Wang, Chu; Yu, Linxiao

    2011-03-15

    On-road measurement is an effective method to investigate real-world emissions generated from vehicles and estimate the difference between engine certification cycles and real-world operating conditions. This study presents the results of on-road measurements collected from urban buses which propelled by diesel engine in Beijing city. Two widely used Euro III emission level buses and two Euro IV emission level buses were chosen to perform on-road emission measurements using portable emission measurement system (PEMS) for gaseous pollutant and Electric Low Pressure Impactor (ELPI) for particulate matter (PM) number emissions. The results indicate that considerable discrepancies of engine operating conditions between real-world driving cycles and engine certification cycles have been observed. Under real-world operating conditions, carbon monoxide (CO) and hydrocarbon (HC) emissions can easily meet their respective regulations limits, while brake specification nitrogen oxide (bsNO(x)) emissions present a significant deviation from its corresponding limit. Compared with standard limits, the real-world bsNO(x) emission of the two Euro III emission level buses approximately increased by 60% and 120% respectively, and bsNO(x) of two Euro IV buses nearly twice standard limits because Selective Catalytic Reduction (SCR) system not active under low exhaust temperature. Particle mass were estimated via particle size distribution with the assumption that particle density and diameter is liner. The results demonstrate that nanometer size particulate matter make significant contribution to total particle number but play a minor role to total particle mass. It is suggested that specific certified cycle should be developed to regulate bus engines emissions on the test bench or use PEMS to control the bus emissions under real-world operating conditions.

  4. Loss/gain on ignition testing for HC-21C

    Energy Technology Data Exchange (ETDEWEB)

    De Vries, M.L.

    1994-12-12

    The HC-21C thermal stabilization process stabilizes reactive plutonium bearing material for long term storage. A Loss On Ignition (LOI) analysis is performed on all materials that are stabilized in the muffle furnaces prior to being stored in the vaults to ensure suitability for vault storage. The material is required to have a LOI of less than 1% (OSD-184-00013 Limit). The LOI analysis is performed to assure that all volatiles that could potentially pressurize the sealed containers over long periods of time, like water, have been removed. It is possible, while performing LOI analysis to see a Gain On Ignition (GOI) due to additional oxidation of materials. In the current stabilization campaign, two items processed have had a positive LOI or GOI result. One concern with a GOI is that the weight gain may actually be masking a weight loss. (Reference 15530-94-WSL-156). Other concerns with a GOI result are that the removal of the oxygen could create a vacuum in the product can causing it to collapse during long term storage or the oxidation of material would increase the volume of the solids potentially bulging or rupturing the product container. In the past, GOIs have been seen on items that were processed through Hoskin`s pot furnaces located in glovebox HA-21I. This test plan provides instruction to test causes of a GOI and to ensure the processed material with a GOI result will not cause a problem during long term storage. Product cans that are sampled for LOI and have results showing a gain of weight will be the test items.

  5. Control and reduction of NOx emissions on light hydrocarbons combustion in fluidized bed combustors: a technological prospection surveys; Controle e reducao de emissoes de NOx durante queima de hidrocarbonetos leves em combustores a leito fluidizado: um estudo de prospeccao tecnologica

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Douglas Alves; Winter, Eduardo [Instituto Nacional da Propriedade Industrial (INPI), Rio de Janeiro, RJ (Brazil)

    2008-07-01

    The present paper aims a technological prospecting study of the main technological agents involved in industrial light hydrocarbons combustion process. More specifically, the work approaches technologies applied to nitrogen oxides emissions control and reduction. Nitrogen oxides are typically known as 'NOx' (NO, N{sub 2}O, NO{sub 2}). 'NOx' are byproducts from fuel burning in combustion systems, including also in fluidized bed combustion systems. The technological prospecting study employed 'technology foresight' as tool for evaluating the technological perspectives of the thermal generation, basis on environment protection. Such technological perspectives of the thermal generation were evaluated through invention patent documents. The query methodology for obtaining of patent documents employed a free patent base, known as ESPACENET. Additionally, the documents obtained were evaluated, considering beyond the countries and the publication dates, technological perspectives employed to 'NOx' emissions control and reduction. It is very important to highlight around 70% of the industrial technological information are just found in invention patent documents. (author)

  6. Emission inventory for mobile sources in a local level into the Metropolitan Zone of the Mexican Valley (MZMV), with atmospheric modeling purposes

    Energy Technology Data Exchange (ETDEWEB)

    Tejeda, D.; Montufar, P.; Aguilar, A.; Velazquez, A. [Centro de Investigacion en Calidad Ambiental, Tec de Monterrey, Campus Estado de Mexico (Mexico)

    2004-07-01

    A common weakness into the implementation and application of the regional air quality models is the truthfulness of the data that are the inputs on that tools, the reason is that the diagnostic and prognostic can be obtained when we apply air quality models is directly proportional to the quality of input data. Due to previous, this work has been focused specifically to develop the emissions inventory to the atmosphere for mobile sources, due to this type of emission source is the most difficult to distribute spatially and temporally. At present, the emissions inventory that has been estimated in the region of Mexico Valley are global and with methodology that are different to the zone of study. In fact, these emissions inventory had been used to apply and implement photochemical models into the Mexican Valley. The methodology that is used in this paper is the typical to estimate the emission inventory for mobile sources, using activity data and emission factors. This methodology is different because it was couple to be used at local level, which allow diminish the uncertainty of the emission inventory. On the other hand, the emission inventory was distributed hourly and spaced by each route whit greater certainty. The pollutants than we estimated are: total hydrocarbons (HC), oxide nitrogen (NO{sub x}), and monoxide carbon (CO) at local level for primary and secondary road. This emission inventory is distinguish from others, because it include vehicle profile for each category and the emissions were distribute, percently, by each day of the week. (orig.)

  7. Precise observations of the 12C/13C ratios of HC3N in the low-mass star-forming region L1527

    CERN Document Server

    Araki, Mitsunori; Sakai, Nami; Yamamoto, Satoshi; Oyama, Takahiro; Kuze, Nobuhiko; Tsukiyama, Koichi

    2016-01-01

    Using the Green Bank 100 m telescope and the Nobeyama 45 m telescope, we have observed the rotational emission lines of the three 13C isotopic species of HC3N in the 3 and 7 mm bands toward the low-mass star-forming region L1527 in order to explore their anomalous 12C/13C ratios. The column densities of the 13C isotopic species are derived from the intensities of the J = 5-4 lines observed at high signal-to-noise ratios. The abundance ratios are determined to be 1.00:1.01 +- 0.02:1.35 +- 0.03:86.4 +- 1.6 for [H13CCCN]:[HC13CCN]:[HCC13CN]:[HCCCN], where the errors represent one standard deviation. The ratios are very similar to those reported for the starless cloud, Taurus Molecular Cloud-1 Cyanopolyyne Peak (TMC-1 CP). These ratios cannot be explained by thermal equilibrium, but likely reflect the production pathways of this molecule. We have shown the equality of the abundances of H13CCCN and HC13CCN at a high-confidence level, which supports the production pathways of HC3N via C2H2 and C2H2+. The average 12...

  8. Differentiation of migrainous positional vertigo (MPV) from horizontal canal benign paroxysmal positional vertigo (HC-BPPV).

    Science.gov (United States)

    Roberts, Richard A; Gans, Richard E; Kastner, Allison H

    2006-04-01

    This article presents an approach to differentiation of migrainous positional vertigo (MPV) from horizontal canal benign paroxysmal positional vertigo (HC-BPPV). Such an approach is essential because of the difference in intervention between the two disorders in question. Results from evaluation of the case study presented here revealed a persistent ageotropic positional nystagmus consistent with MPV or a cupulolithiasis variant of HC-BPPV. The patient was treated with liberatory maneuvers to remove possible otoconial debris from the horizontal canal in an attempt, in turn, to provide further diagnostic information. There was no change in symptoms following treatment for HC-BPPV. This case was diagnosed subsequently as MPV, and the patient was referred for medical intervention. Treatment has been successful for 22 months. Incorporation of HC-BPPV treatment, therefore, may provide useful information in the differential diagnosis of MPV and the cupulolithiasis variant of HC-BPPV.

  9. CID: Chemistry In Disks VII. First detection of HC3N in protoplanetary disks

    CERN Document Server

    Chapillon, E; Guilloteau, S; Pietu, V; Wakelam, V; Hersant, F; Gueth, F; Henning, T; Launhardt, R; Schreyer, K; Semenov, D

    2012-01-01

    Molecular line emission from protoplanetary disks is a powerful tool to constrain their physical and chemical structure. Nevertheless, only a few molecules have been detected in disks so far. We take advantage of the enhanced capabilities of the IRAM 30m telescope by using the new broad band correlator (FTS) to search for so far undetected molecules in the protoplanetary disks surrounding the TTauri stars DM Tau, GO Tau, LkCa 15 and the Herbig Ae star MWC 480. We report the first detection of HC3N at 5 sigma in the GO Tau and MWC 480 disks with the IRAM 30-m, and in the LkCa 15 disk (5 sigma), using the IRAM array, with derived column densities of the order of 10^{12}cm^{-2}. We also obtain stringent upper limits on CCS (N < 1.5 x 10^{12} cm^{-3}). We discuss the observational results by comparing them to column densities derived from existing chemical disk models (computed using the chemical code Nautilus) and based on previous nitrogen and sulfur-bearing molecule observations. The observed column densiti...

  10. Organic geochemistry of the Vindhyan sediments: Implications for hydrocarbons

    Science.gov (United States)

    Dayal, A. M.; Mani, Devleena; Madhavi, T.; Kavitha, S.; Kalpana, M. S.; Patil, D. J.; Sharma, Mukund

    2014-09-01

    The organic geochemical methods of hydrocarbon prospecting involve the characterization of sedimentary organic matter in terms of its abundance, source and thermal maturity, which are essential prerequisites for a hydrocarbon source rock. In the present study, evaluation of organic matter in the outcrop shale samples from the Semri and Kaimur Groups of Vindhyan basin was carried out using Rock Eval pyrolysis. Also, the adsorbed low molecular weight hydrocarbons, methane, ethane, propane and butane, were investigated in the near surface soils to infer the generation of hydrocarbons in the Vindhyan basin. The Total Organic Carbon (TOC) content in shales ranges between 0.04% and 1.43%. The S1 (thermally liberated free hydrocarbons) values range between 0.01-0.09 mgHC/gRock (milligram hydrocarbon per gram of rock sample), whereas the S2 (hydrocarbons from cracking of kerogen) show the values between 0.01 and 0.14 mgHC/gRock. Based on the Tmax (temperature at highest yield of S2) and the hydrogen index (HI) correlations, the organic matter is characterized by Type III kerogen. The adsorbed soil gas, CH4 (C1), C2H6 (C2), C3H8 (C3) and nC4H10, (nC4), concentrations measured in the soil samples from the eastern part of Vindhyan basin (Son Valley) vary from 0 to 186 ppb, 0 to 4 ppb, 0 to 5 ppb, and 0 to 1 ppb, respectively. The stable carbon isotope values for the desorbed methane (δ13C1) and ethane (δ13C2) range between -45.7‰ to -25.2‰ and -35.3‰ to -20.19‰ (VPDB), respectively suggesting a thermogenic source for these hydrocarbons. High concentrations of thermogenic hydrocarbons are characteristic of areas around Sagar, Narsinghpur, Katni and Satna in the Son Valley. The light hydrocarbon concentrations (C1-C4) in near surface soils of the western Vindhyan basin around Chambal Valley have been reported to vary between 1-2547 ppb, 1-558 ppb, 1-181 ppb, 1-37 ppb and 1-32 ppb, respectively with high concentrations around Baran-Jhalawar-Bhanpur-Garot regions (Kumar

  11. Real-world emissions from model year 1993, 2000, and 2010 passenger cars

    Energy Technology Data Exchange (ETDEWEB)

    Ross, M.; Goodwin, R.; Watkins, R. [and others

    1995-11-01

    Air pollution by cars and light trucks is a major problem in metropolitan areas in the United States and around the world. Much of the discussion of this issue is based on the emissions per vehicle mile as determined under somewhat artificial testing conditions. The pollutants actually emitted vary considerably with the particular vehicle and the way it is driven, but the average emissions per mile are much higher than the test values. This report concerns the sources and levels of excess emissions, and the potential for reducing them. The history of automotive emissions regulation reveals remarkable success in reducing the emissions of carbon monoxide (CO), hydrocarbons (HC) and oxides of nitrogen (NO{sub x}) from new automobiles - as measured in certification tests. The grams-per-mile (g/mile) standards for these tests are stringent, with 96% reductions mandated in comparison to the estimated pre-control (mid-1960s) levels for CO and HC; and 75% reductions mandated for NO{sub x}. Powerful new technologies have been developed and incorporated into every new vehicle in order to accomplish these reductions. Most noteworthy are the catalytic converter and closed-loop engine controls; the latter includes sensors before and after the engine proper, and computer analysis of the information leading to real-time control of fuel injection, with the principal objective of maintaining just the right chemical balance of fuel and air. The average lifetime real-world g/mile emissions associated with conventional gasoline fueled cars for model years 1993, 2000, and 2010 have been projected. Results are discussed.

  12. 针对访问驱动cache攻击HC-256算法的改进%Improved algorithm for HC-256 to access-driven cache attack

    Institute of Scientific and Technical Information of China (English)

    郑继森; 谭晓青; 莫庆平; 贺婵

    2011-01-01

    In order to defense against the access-driven cache attack, this paper improved the stream cipher HC-256.Added full random sort algorithm to the HC-256, which disrupted the order of the tables P and Q.This paper used variable tables instead of ( fixed content) S-boxes, and it gave the adversary insecurity both about the input and the output of the tables.It defenses against the access-driven cache attack effectively.%为了使HC-256可以防御访问驱动cache攻击,对HC-256算法进行了改进.在HC-256中加入完全随机排序算法,对表P和表Q进行扰乱,这样使用变化的表代替固定的S盒,使得攻击者获得的输入和输出都是不安全的,有效地防御了此访问驱动cache攻击.

  13. Hydrogenated Polycyclic Aromatic Hydrocarbons and the 2940 and 2850 Wavenumber (3.40 and 3.51 micron) Infrared Emission Features

    Science.gov (United States)

    Bernstein, Max P.; Sandford, Scott A.; Allamadola, Louis J.

    1996-01-01

    The 3150-2700/cm (3.17-3.70 micron) range of the spectra of a number of Ar-matrix-isolated PAHs containing excess H atoms (H(sub n)-PAHS) are presented. This region covers features produced by aromatic and aliphatic C-H stretching vibrations as well as overtone and combination bands involving lower lying fundamentals. The aliphatic C-H stretches in molecules of this type having low to modest excess H coverage provide excellent fits to a number of the weak emission features superposed on the plateau between 3080 and 2700/cm (3.25 and 3.7 micron) in the spectra of many planetary nebulae, reflection nebulae, and H II regions. Higher H coverage is implied for a few objects. We compare these results in context with the other suggested identifications of the emission features in the 2950-2700/cm (3.39-3.70 micron) region and briefly discuss their astrophysical implications.

  14. Analysis of Emission from Petrol Vehicles in the Koforidua Municipality, Ghana

    Directory of Open Access Journals (Sweden)

    Gyamfi Bright George

    2017-03-01

    Full Text Available Koforidua has seen its fair share in the increase in the number of cars on its roads over the past decade. This has resulted in progressive increase in traffic congestion on the roads and could lead to deterioration in the air quality. Exhaust gas emissions from a total of 104 vehicles were tested with an exhaust gas analyzer. Hydrocarbons (HC, Carbon dioxide (CO2 and Carbon monoxide (CO were measured and compared with EU standards for gasoline vehicles and Auto Data Technical information. A series of algorithms developed using Microsoft Excel Spread Sheet were used to analyze the data collected. Out of the total number of cars tested, 74 and 80 cars passed the HC and CO tests respectively. 10 cars out of the total were rated as good under CO2 test. In total, 69.5% of the cars tested passed the various tests conducted and about 73 cars representing 70.2% of the cars tested were over 10 years and the emission standards for those years were flexible.

  15. Raman characteristics of hydrocarbon and hydrocarbon inclusions

    Institute of Scientific and Technical Information of China (English)

    ZHANG Nai; TIAN ZuoJi; LENG YingYing; WANG HuiTong; SONG FuQing; MENG JianHua

    2007-01-01

    The Raman spectrograms of hydrocarbon standard samples show that: (1) the Raman spectrogram of normal paraffin has very strong peaks of methyl and methylene (from 2700 cm-1 to 2970 cm-1); (2)branch methyl has the particular peak of 748 cm-1±; (3) six cyclic has the particular peak of 804 cm-1±; (4)phenyl has two particular peaks of 988 cm-1± and 3058 cm-1± and the 988 cm-1± peak is stronger than the 3058 cm-1± peak; and (5) hexene has three alkenyl spectrum peaks of 1294 cm-1±, 1635 cm-1± and 2996 cm-1±, with the 1635 cm-1± peak being the strongest, showing that the number of carbon in hydrocarbon does not affect its Raman spectrogram, and the hydrocarbon molecular structure and base groups affect its Raman spectrogram, the same hydrocarbons (such as normal paraffin) have the same Raman spectrogram; the types (such as CH4, C2H6, C3H8) and the content of hydrocarbon in oil inclusions are not estimated by their characteristic Raman peaks. According to the Raman spectrograms of hydrocarbon compositions, the Raman spectrogram of hydrocarbon inclusion can be divided into five types: saturated hydrocarbon Raman spectrogram, fluoresce Raman spectrogram, saturated hydrocarbon bitumen Raman spectrogram, bitumen Raman spectrogram, and ethane Raman spectrogram.And according to the characteristics of Raman spectrogram, hydrocarbon inclusions can be divided into five types: saturated hydrocarbon inclusion, less saturated hydrocarbon (oil or gas) inclusion,saturated hydrocarbon bitumen inclusion, bitumen inclusion, and methane water inclusion.

  16. Raman characteristics of hydrocarbon and hydrocarbon inclusions

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The Raman spectrograms of hydrocarbon standard samples show that: (1) the Raman spectrogram of normal paraffin has very strong peaks of methyl and methylene (from 2700 cm-1 to 2970 cm-1); (2) branch methyl has the particular peak of 748 cm-1±; (3) six cyclic has the particular peak of 804 cm-1±; (4) phenyl has two particular peaks of 988 cm-1± and 3058 cm-1± and the 988 cm-1± peak is stronger than the 3058 cm-1± peak; and (5) hexene has three alkenyl spectrum peaks of 1294 cm-1±, 1635 cm-1± and 2996 cm-1±, with the 1635 cm-1± peak being the strongest, showing that the number of carbon in hy-drocarbon does not affect its Raman spectrogram, and the hydrocarbon molecular structure and base groups affect its Raman spectrogram, the same hydrocarbons (such as normal paraffin) have the same Raman spectrogram; the types (such as CH4, C2H6, C3H8) and the content of hydrocarbon in oil inclu-sions are not estimated by their characteristic Raman peaks. According to the Raman spectrograms of hydrocarbon compositions, the Raman spectrogram of hydrocarbon inclusion can be divided into five types: saturated hydrocarbon Raman spectrogram, fluoresce Raman spectrogram, saturated hydro-carbon bitumen Raman spectrogram, bitumen Raman spectrogram, and ethane Raman spectrogram. And according to the characteristics of Raman spectrogram, hydrocarbon inclusions can be divided into five types: saturated hydrocarbon inclusion, less saturated hydrocarbon (oil or gas) inclusion, saturated hydrocarbon bitumen inclusion, bitumen inclusion, and methane water inclusion.

  17. Automobile emissions in Mexico City

    Energy Technology Data Exchange (ETDEWEB)

    Beaton, S.; Bishop, G.; Stedman, D.

    1996-09-01

    In order to determine the exhaust characteristics of the Mexico City vehicle fleet, a Fuel Efficiency Automotive Test (FEAT) unit was placed at 5 different sites over a 10 day period from 11 February 1991 through 21 February 1991. Valid data for the percent of carbon Monoxide (CO), hydrocarbons (HC), and carbon dioxide (CO{sub 2}) were obtained on 31 838 vehicles. This represents approximately 1 % of the entire Mexico City fleet.

  18. Sequence stratigraphic control on prolific HC reservoir development, Southwest Iran

    Science.gov (United States)

    Lasemi, Y.; Kondroud, K.N.

    2008-01-01

    An important carbonate formation in the Persian Gulf and the onshore oil fields of Southwest Iran is the Lowermost Cretaceous Fahliyan formation. The formation in Darkhowain field consists of unconformity-bounded depositional sequences containing prolific hydrocarbon reservoirs of contrasting origin. Located in the high stand systems tract (HST) of the lower sequence encompassing over 200m of oil column are the most prolific reservoir. Another reservoir is over 80m thick consisting of shallowing-upward cycles that are best developed within the transgressive systems tract of the upper sequence. Vertical facies distribution and their paleobathymetry and geophysical log signatures of the Fahliyan formation in the Darkhowain platform reveal the presence of two unconformity-bounded depositional sequences in Vail et al., Van Wagoner et al., and Sarg. The Fahliyan formation mainly consists of platform carbonates composed of restricted bioclastic lime mudstone to packstone of the platform interior, Lithocodium boundstone or ooid-intraclast-bioclast grainstone of the high energy platform margin and the bioclast packstone to lime mudstone related to the off-platform setting.

  19. Emissions of particulate matter and associated polycyclic aromatic hydrocarbons from agricultural diesel engine fueled with degummed,deacidified mixed crude palm oil blends

    Institute of Scientific and Technical Information of China (English)

    Khamphe Phoungthong; Surajit Tekasakul; Perapong Tekasakul; Gumpon Prateepchaikul; Naret Jindapetch; Masami Furuuchi; Mitsuhiko Hata

    2013-01-01

    Mixed crude palm oil (MCPO),the mixture of palm fiber oil and palm kernel oil,has become of great interest as a renewable energy source.It can be easily extracted from whole dried palm fruits.In the present work,the degummed,deacidified MCPO was blended in petroleum diesel at portions of 30% and 40% by volume and then tested in agricultural diesel engines for long term usage.The particulates from the exhaust of the engines were collected every 500 hr using a four-stage cascade air sampler.The 50% cut-off aerodynamic diameters for the first three stages were 10,2.5 and 1 μm,while the last stage collected all particles smaller than 1 μm.Sixteen particle bounded polycyclic aromatic hydrocarbons (PAHs) were analyzed using a high performance liquid chromatography.The results indicated that the size distribution of particulate matter was in the accumulation mode and the pattern of total PAHs associated with fine-particles (< 1 μm) showed a dominance of larger molecular weight PAHs (4-6 aromatic rings),especially pyrene.The mass median diameter,PM and total PAH concentrations decreased when increasing the palm oil content,but increased when the running hours of the engine were increased.In addition,Commercial petroleum diesel (PB0) gave the highest value of carcinogenic potency equivalent (BaPeq) for all particle size ranges.As the palm oil was increased,the BaPeq decreased gradually.Therefore the degummed-deacidified MCPO blends are recommended for diesel substitute.

  20. Global Assessment of Hydrogen Technologies - Task 2 Report Comparison of Performance and Emissions from Near-Term Hydrogen Fueled Light Duty Vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Fouad, Fouad H.; Peters, Robert W.; Sisiopiku, Virginia P.; Sullivan Andrew J.; Ng, Henry K.; Waller, Thomas

    2007-12-01

    An investigation was conducted on the emissions and efficiency from hydrogen blended compressed natural gas (CNG) in light duty vehicles. The different blends used in this investigation were 0%, 15%, 30%, 50%, 80%, 95%, and ~100% hydrogen, the remainder being compressed natural gas. The blends were tested using a Ford F-150 and a Chevrolet Silverado truck supplied by Arizona Public Services. Tests on emissions were performed using four different driving condition tests. Previous investigation by Don Karner and James Frankfort on a similar Ford F-150 using a 30% hydrogen blend showed that there was substantial reduction when compared to gasoline in carbon monoxide (CO), nitrogen oxide (NOx), and carbon dioxide (CO2) emissions while the reduction in hydrocarbon (HC) emissions was minimal. This investigation was performed using different blends of CNG and hydrogen to evaluate the emissions reducing capabilities associated with the use of the different fuel blends. The results were then tested statistically to confirm or reject the hypotheses on the emission reduction capabilities. Statistically analysis was performed on the test results to determine whether hydrogen concentration in the HCNG had any effect on the emissions and the fuel efficiency. It was found that emissions from hydrogen blended compressed natural gas were a function of driving condition employed. Emissions were found to be dependent on the concentration of hydrogen in the compressed natural gas fuel blend.

  1. 40 CFR 91.104 - Exhaust emission standards for outboard and personal watercraft engines.

    Science.gov (United States)

    2010-07-01

    ... procedure in § 91.207 to determine compliance with the corporate average HC+NOX exhaust emission standard... PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM MARINE SPARK-IGNITION..., for their useful life. (d) A manufacturer must comply with a corporate average HC+NOX...

  2. 太原市多环芳烃(PAHs)排放清单与分布特征分析%Estimation of annual emission and distribution characteristics of polycyclic aromatic hydrocarbons (PAHs) in Taiyuan

    Institute of Scientific and Technical Information of China (English)

    蒋秋静; 李跃宇; 胡新新; 卢彬; 陶澍; 王戎

    2013-01-01

    根据太原市11种主要排放源的排放因子和活动量数据,估算了美国国家环境保护局(US EPA)优先控制污染物清单中16种多环芳烃(PAHs)的年排放量.结果表明2010年太原市16种PAHs的排放量约为332.10t,其中7种致癌性PAHs排放总量为35.11t.从排放源看,生活燃煤和炼焦煤是太原市排放PAHs的主要来源,占总排放量的65%以上.从各地区的PAHs排放情况看,排放量最大的地区是清徐县(87t/a),占总排放的27%.其次为古交市(54t/a)、晋源区(44t/a)、尖草坪区(40t/a).各地区人均收入与单位GDP排放量之间呈负相关(R2=0.727);各地区PAHs排放量与农村人口之间呈正相关(R2=0.813),从排放谱看,排放以低环PAHs为主(81%),致癌性PAHs占总排放量的10.6%.结果表明,太原市PAHs的排放与太原市特殊的能源结构和人群结构有关.%Sixteen types of polycyclic aromatic hydrocarbons (PAHs) were included in the priority control pollutants listed by the U.S. Environmental Protection Agency (US EPA). Herein, the emission rates and emission sources of these 16 PAHs in Taiyuan city were investigated. Results showed that the overall emission amount of the 16 PAHs in the year of 2010 in Taiyuan was 332.10t, in which 35.11t was identified as carcinogenic PAHs. Most of the PAHs were generated from the combustion of household coal and coke-production coal, accounting for 65% of the total emission amount. Among the emissions of 16 PAHs, less-ring PAHs were the majority (81%) while the carcinogenic PAHs only accounted for 10.6%. For the different districts (10 in total) in Taiyuan, the PAHs emitted from Qingxu were 87t/a, greatly more than that from Gujiao (54t/a), Jinyuan (44t/a), and Jiancaoping (40t/a). In general, there were a negative correlation between per capita income and per GDP emissions of PAHs (R2=0.727), and a positive correlation between the rural population and total PAHs emissions (R2=0.813). It was concluded that the heavy

  3. Methane Conversion to C2 Hydrocarbons Using Glow Discharge Plasma

    Institute of Scientific and Technical Information of China (English)

    HU Miao; CHEN Jierong

    2007-01-01

    The infrared emission spectra of methane, H', CH and C2 hydrocarbons in natural gas were measured. The process of methane decomposition and C2 hydrocarbons formation was investigated. The experiment showed that the time and conditions of methane decomposition and C2 hydrocarbons formation were different. Methane conversion rate increased with the increase in the current and decrease in the amount of methane. Furthermore, an examination of the reaction mechanisms revealed that free radicals played an important role in the chain reaction.

  4. Emission factors of air pollutants from CNG-gasoline bi-fuel vehicles: Part I. Black carbon.

    Science.gov (United States)

    Wang, Yang; Xing, Zhenyu; Xu, Hui; Du, Ke

    2016-12-01

    Compressed natural gas (CNG) is considered to be a "cleaner" fuel compared to other fossil fuels. Therefore, it is used as an alternative fuel in motor vehicles to reduce emissions of air pollutants in transportation. To quantify "how clean" burning CNG is compared to burning gasoline, quantification of pollutant emissions under the same driving conditions for motor vehicles with different fuels is needed. In this study, a fleet of bi-fuel vehicles was selected to measure the emissions of black carbon (BC), carbon monoxide (CO), hydrocarbon (HC) and nitrogen oxide (NOx) for driving in CNG mode and gasoline mode respectively under the same set of constant speeds and accelerations. Comparison of emission factors (EFs) for the vehicles burning CNG and gasoline are discussed. This part of the paper series reports BC EFs for bi-fuel vehicles driving on the real road, which were measured using an in situ method. Our results show that burning CNG will lead to 54%-83% reduction in BC emissions per kilometer, depending on actual driving conditions. These comparisons show that CNG is a cleaner fuel than gasoline for motor vehicles in terms of BC emissions and provide a viable option for reducing BC emissions cause by transportation. Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Emission of polycyclic aromatic hydrocarbons (PAHs and benzene, toluene, ethylbenzene and xylene (BTEX from the furan moulding sands with addition of the reclaim

    Directory of Open Access Journals (Sweden)

    M. Holtzer

    2014-10-01

    Full Text Available In this paper, the results of decomposition of a moulding sand with furfuryl resin also on a quartz matrix and with additions of a reclaimed material, under industrial conditions, are presented. Investigations of the gases emission in the test foundry plant were performed according to the original method developed in the Faculty of Foundry Engineering, AGH UST. The dependence of the emitted PAHs and BTEX group substances and ignition losses on the reclaim fraction in a moulding sand are of a linear character of a very high correlation coefficient R2. On the bases of the derived equations, it is possible to determine the amount of the emitted hazardous substances from the moulding sand containing the known fraction of the reclaim.

  6. Observation of the h_c(1P) using e^+e^- collisions above DDbar threshold

    CERN Document Server

    Pedlar, T K; Hietala, J; Dobbs, S; Metreveli, Z; Seth, K K; Tomaradze, A; Xiao, T; Martin, L; Powell, A; Wilkinson, G; Mendez, H; Ge, J Y; Miller, D H; Shipsey, I P J; Xin, B; Adams, G S; Hu, D; Moziak, B; Napolitano, J; Ecklund, K M; Insler, J; Muramatsu, H; Park, C S; Pearson, L J; Thorndike, E H; Ricciardi, S; Thomas, C; Artuso, M; Blusk, S; Mountain, R; Skwarnicki, T; Stone, S; Zhang, L M; Bonvicini, G; Cinabro, D; Lincoln, A; Smith, M J; Zhou, P; Zhu, J; Naik, P; Rademacker, J; Asner, D M; Edwards, K W; Randrianarivony, K; Tatishvili, G; Briere, R A; Vogel, H; Onyisi, P U E; Rosner, J L; Alexander, J P; Cassel, D G; Das, S; Ehrlich, R; Gibbons, L; Gray, S W; Hartill, D L; Heltsley, B K; Kreinick, D L; Kuznetsov, V E; Patterson, J R; Peterson, D; Riley, D; Ryd, A; Sadoff, A J; Shi, X; Sun, W M; Yelton, J; Rubin, P; Lowrey, N; Mehrabyan, S; Selen, M; Wiss, J; Libby, J; Kornicer, M; Mitchell, R E; Shepherd, M R; Tarbert, C M; Besson, D

    2011-01-01

    Using 586pb^-1 of e^+e^- collision data at Ecm = 4170MeV, produced at the CESR collider and collected with the CLEO-c detector, we observe the process e^+e^- --> pi^+ pi^- h_c(1P) with a significance of greater than 10 sigma. We measure its cross section to be 15.6+-2.3+-1.9+-3.0pb, where the third error is due to the external uncertainty on the branching fraction of psi(2S) --> pi^0 h_c(1P), which we use for normalization. We also find evidence for e^+e^- --> eta h_c(1P) at 4170MeV at the 3 sigma level, and see hints of a rise in the e^+e^- --> pi^+ pi^- h_c(1P) cross section at 4260MeV.

  7. Caracterizacion del desarrollo y absorcion de nutrimentos del hibrido de maiz HC-57

    National Research Council Canada - National Science Library

    Fallas, Roger; Bertsch, Floria; Echandi, Carlos; Henriquez, Carlos

    2011-01-01

    En la Estacion Experimental Agricola Fabio Baudrit Moreno, Alajuela, Costa Rica se realizo un ensayo con el objetivo de determinar la absorcion de nutrimentos por parte del hibrido comercial de maiz HC-57...

  8. Oxidation of gaseous hydrocarbons by alkene-utilizing bacteria

    NARCIS (Netherlands)

    Ginkel, van C.G.

    1987-01-01

    Gaseous alkenes are widespread in the environment due to the emission of these hydrocarbons by industry and due to their production from natural sources as for instance ethene by plants, fungi and bacteria. Micro-organisms have developed the potential to oxidize these hydrocarbons. Alkenes

  9. Oxidation of gaseous hydrocarbons by alkene-utilizing bacteria.

    NARCIS (Netherlands)

    Ginkel, van C.G.

    1987-01-01

    Gaseous alkenes are widespread in the environment due to the emission of these hydrocarbons by industry and due to their production from natural sources as for instance ethene by plants, fungi and bacteria. Micro-organisms have developed the potential to oxidize these hydrocarbons. Alkenes can eithe

  10. Condiciones físicas de la envoltura de baja velocidad de CRL618 derivadas de modos vibracionalmente excitados de HC3N

    Science.gov (United States)

    Pardo, J. R.; Cernicharo, J.; Goicoechea, J. R.

    The complete sequence of HC3N rotational lines from J=9-8 to J=30-29 has been observed with the IRAM 30m telescope toward the protoplanetary nebula CRL618. A total of 15 different vibrational states (including the fundamental) with energies up to 1100 cm-1 have been detected. The CSO telescope has been used to complement this study in the range Jup 31 to 39, with detections in five of these vibrational states, all of them below 700 cm-1. The lines from HC3N, its isotopic substituted species, and from HC5N, produce crowded millimeter and submillimeter wave spectra in CRL618. Only the rotational lines of HC3N in its ground vibrational state display evidence of the high velocity outflow first detected by Cernicharo et al. 1989. Vibrationally excited HC3N rotational lines exhibit P-Cygni profiles at 3 mm, known also in many other species in this object, evolving to pure emission at shorter wavelengths in a way slightly dependent on the vibrational state. The absorption features are formed against a continuum that averages ˜ 0.3 K in the TA* scale across the entire frequency range covered by the IRAM 30m telescope and is about 0.06 K in the frequency range scanned with the CSO (same scale). These results translate into integrated fluxes ranging from 1.75 Jy to 3.4 Jy in the frequency range 90 to 240 GHz, which subsequently translates into effective temperatures of the continuum source at 90 GHz ranging from 8700 to 15000 K for sizes between 0.18'' and 0.15'', with spectral indexes between -1.15 and -1.12. We have made an effort to simultaneously fit all observed HC3N ladders through a LTE radiative transfer model for HC3N in an expanding shell around the central and ultracompact HII region. We have explored both the spherical and the elongated shell cases. The simulations show evidence that the inner slowly expanding envelope has temperatures around 300 K, expansion and turbulence velocities of ˜ 5-13 and around 2.5 kms-1 respectively, and is possibly inclined respect

  11. 蚊香燃烧过程中多环芳烃的排放特征%EMISSION CHARACTERISTICS OF POLYCYCLIC AROMATIC HYDROCARBONS FROM MOSQUITO COIL BURNING

    Institute of Scientific and Technical Information of China (English)

    周宏仓; 宋园园; 陆建刚; 李红双; 蔡华侠; 赵晓莉

    2009-01-01

    对3种类型蚊香(有烟蚊香、微烟蚊香和无烟蚊香)原料、灰烬及烟气样品经索式提取、K-D浓缩和硅胶层析纯化后,采用GC-MS分析其US EPA推荐的16种优控多环芳烃的含量.结果表明,有烟蚊香和微烟蚊香烟气中多环劳烃总含量高于原料中的含量,无烟蚊香则相反.有烟蚊香和微烟蚊香原料以3环和4环多环芳烃为主,无烟蚊香原料以2环和3环多环芳烃为主,3种类型蚊香灰烬和烟气中多环芳烃均以2环、3环和4环化合物为主.通过对比蚊香燃烧前、后样品中多环芳烃的毒性,发现同原料相比,有烟蚊香燃烧后烟气中多环芳烃的毒性显著增加,而微烟蚊香和无烟蚊香则明显减少.%For the determination of 16 priority-controlled polycyclic aromatic hydrocarbons(PAHs) recommended by US EPA in raw material, ash and smoke of three types of mosquito coils (smoke mosquito coil, micro-smoke mosquito coil and smokeless mosquito coil) by GC-MS, the samples were extracted in a Soxhlet extractor, concentrated in a K-D apparatus, and separated in a silica gel clean-up column. The results show that the total PAHs contents in the smoke are higher than those in the raw material for smoke and micro-smoke mosquito coils, while the status reverse for smokeless mosquito coil PAHs in the raw material of smoke and micro-smoke mosquito coils are dominated by 3-ring and 4-ring PAHs, while 2-ring and 3-ring PAHs are predominant in the raw material of smokeless mosquito coil. Both the ash samples and smoke samples of three mosquito coils are dominated by 2-ring, 3-ring and 4-ring PAHs. By comparison of toxic parameters between smoke and raw material of mosquito coils, the toxic equivalent of PAHs in the smoke increases obviously for smoke mosquito coil, while the status reverse for micro-smoke and smokeless mosquito coils.

  12. In vitro production and antifungal activity of peptide ABP-dHC-cecropin A.

    Science.gov (United States)

    Zhang, Jiaxin; Movahedi, Ali; Xu, Junjie; Wang, Mengyang; Wu, Xiaolong; Xu, Chen; Yin, Tongming; Zhuge, Qiang

    2015-04-10

    The antimicrobial peptide ABP-dHC-cecropin A is a small cationic peptide with potent activity against a wide range of bacterial species. Evidence of antifungal activity has also been suggested; however, testing of this peptide has been limited due to the low expression of cecropin proteins in Escherichia coli. To improve expression of this peptide in E. coli, ABP-dHC-cecropin A was cloned into a pSUMO vector and transformed into E. coli, resulting in the production of a pSUMO-ABP-dHC-cecropin A fusion protein. The soluble form of this protein was then purified by Ni-IDA chromatography, yielding a total of 496-mg protein per liter of fermentation culture. The SUMO-ABP-dHC-cecropin A fusion protein was then cleaved using a SUMO protease and re-purified by Ni-IDA chromatography, yielding a total of 158-mg recombinant ABP-dHC-cecropin A per liter of fermentation culture at a purity of ≥94%, the highest yield reported to date. Antifungal activity assays performed using this purified recombinant peptide revealed strong antifungal activity against both Candida albicans and Neurospora crassa, as well as Rhizopus, Fusarium, Alternaria, and Mucor species. Combined with previous analyses demonstrating strong antibacterial activity against a number of important bacterial pathogens, these results confirm the use of ABP-dHC-cecropin A as a broad-spectrum antimicrobial peptide, with significant therapeutic potential.

  13. Microbiological aspects of the removal of chlorinated hydrocarbons from air

    NARCIS (Netherlands)

    Dolfing, Jan; Wijngaard, Arjan J. van den; Janssen, Dick B.

    1993-01-01

    Chlorinated hydrocarbons are widely used synthetic chemicals that are frequently present in industrial emissions. Bacterial degradation has been demonstrated for several components of this class of compounds. Structural features that affect the degradability include the number of chlorine atoms and

  14. Microbiological aspects of the removal of chlorinated hydrocarbons from air

    NARCIS (Netherlands)

    Dolfing, Jan; Wijngaard, Arjan J. van den; Janssen, Dick B.

    1993-01-01

    Chlorinated hydrocarbons are widely used synthetic chemicals that are frequently present in industrial emissions. Bacterial degradation has been demonstrated for several components of this class of compounds. Structural features that affect the degradability include the number of chlorine atoms and

  15. Polycyclic Aromatic Hydrocarbons

    Science.gov (United States)

    Salama, Farid

    2010-01-01

    Carbonaceous materials play an important role in space. Polycyclic Aromatic Hydrocarbons (PAHs) are a ubiquitous component of the carbonaceous materials. PAHs are the best-known candidates to account for the IR emission bands. They are also thought to be among the carriers of the diffuse interstellar absorption bands (DIBs). PAH ionization states reflect the ionization balance of the medium while PAH size, composition, and structure reflect the energetic and chemical history of the medium. A major challenge is to reproduce in the laboratory the physical conditions that exist in the emission and absorption interstellar zones. The harsh physical conditions of the ISM -low temperature, collisionless, strong UV radiation fields- are simulated in the laboratory by associating a molecular beam with an ionizing discharge to generate a cold plasma expansion. PAH ions and radicals are formed from the neutral precursors in an isolated environment at low temperature and probed with high-sensitivity cavity ringdown spectroscopy in the NUV-NIR range. Carbon nanoparticles are also formed during the short residence time of the precursors in the plasma and are characterized with time-offlight mass spectrometry. These experiments provide unique information on the spectra of large carbonaceous molecules and ions in the gas phase that can now be directly compared to interstellar and circumstellar observations (IR emission bands, DIBs, extinction curve). These findings also hold great potential for understanding the formation process of interstellar carbonaceous grains. We will review recent progress in the experimental and theoretical studies of PAHs, compare the laboratory data with astronomical observations and discuss the global implications.

  16. Experimental Investigation of 2nd Generation Bioethanol Derived from Empty-fruit-bunch (EFB of Oil-palm on Performance and Exhaust Emission of SI Engine

    Directory of Open Access Journals (Sweden)

    Yanuandri Putrasari

    2014-07-01

    Full Text Available The experimental investigation of 2nd generation bioethanol derived from EFB of oil-palm blended with gasoline for 10, 20, 25% by volume and pure gasoline were conducted on performance and exhaust emission tests of SI engine. A four stroke, four cylinders, programmed fuel injection (PGMFI, 16 valves variable valve timing and electronic lift control (VTEC, single overhead camshaft (SOHC, and 1,497 cm3 SI engine (Honda/L15A was used in this investigation. Engine performance test was carried out for brake torque, power, and fuel consumption. The exhaust emission was analyzed for carbon monoxide (CO and hydrocarbon (HC. The engine was operated on speed range from1,500 until 4,500 rev/min with 85% throttle opening position. The results showed that the highest brake torque of bioethanol blends achieved by 10% bioethanol content at 3,000 to 4,500 rpm, the brake power was greater than pure gasoline at 3,500 to 4,500 rpm for 10% bioethanol, and bioethanol-gasoline blends of 10 and 20% resulted greater bsfc than pure gasoline at low speed from 1,500 to 3,500 rpm. The trend of CO and HC emissions tended to decrease when the engine speed increased.

  17. Additives for rapeseed oil fuel. Influence on the exhaust gas emissions

    Energy Technology Data Exchange (ETDEWEB)

    Kastl, Johannes; Remmele, Edgar; Thuneke, Klaus [Technologie- und Foerderzentrum, Straubing (Germany)

    2013-06-01

    In contrast to fossil diesel fuel, the use of additives is not common in rapeseed oil fuel. In a preceding research project the efficacy of several additives, that are commercially available for the use in fossil diesel or FAME, has been investigated for rapeseed oil fuel in the lab. Four additives could be identified, which have a significant influence on the ignition delay or the low temperature flow behaviour of rapeseed oil fuel. To investigate whether there are negative effects of the additives on other fuel-related properties in practical use, a test series on an agricultural tractor capable of running on vegetable oils has been conducted. Attention is focused on the operating parameters like power, torque or fuel consumption as well as on regulated emissions (CO, HC, particulate matter or NOx) and non-regulated emissions like polycyclic aromatic hydrocarbons. Additionally, the influence of the additives on the storage stability of rapeseed oil fuel is investigated in long term studies. No negative influence of the additives on the regulated emissions could be seen in the experiments, the data of the non-regulated emissions is still being analysed. This paper will focus on the emissions testing; results of the long term studies will be given in the presentation. (orig.)

  18. A comprehensive study on the emission characteristics of E-diesel dual-fuel engine

    Directory of Open Access Journals (Sweden)

    A. Avinash

    2016-03-01

    Full Text Available Each year, the ultimate goal of emission legislation is to force technology to the point where a practically viable zero emission vehicle becomes a reality. Albeit the direction to reach this target is a formidable challenge, homogeneous charge compression ignition (HCCI is a new combustion concept to produce ultra low nitrogen oxides (NOx and smoke emissions. By the way, an endeavor has been made in this work to achieve a simultaneous reduction in both NOx and smoke levels in a direct injection compression ignition engine converted to operate on premixed charge compression ignition mode. Indeed, these promises were made possible in this work by preparing premixed fuel–air mixture outside the engine cylinder. For this purpose, ethanol was injected in the intake port at various premixed ratios (5%, 10%, 15%, 20%, 25% and 30% and conventional diesel was injected as usual. It was extrapolated from the experimental results that e-diesel operation can significantly reduce NOx and smoke levels. In addition, NOx and smoke levels reduced in this experimental study with increase in premixed fraction. Nevertheless, unburned hydrocarbons (UBHC and carbon monoxide (CO emissions exhibited reverse trend with increase in premixed fraction and the maximum value of HC and CO emission levels was noted with 30% premixed fraction.

  19. New detections of HC$_{5}$N toward hot cores associated with 6.7 GHz methanol masers

    CERN Document Server

    Green, Claire-Elise; Burton, Michael G; Horiuchi, Shinji; Tothill, Nicholas F H; Walsh, Andrew J; Purcell, Cormac R; Lovell, James E J; Millar, Thomas J

    2014-01-01

    We present new detections of cyanodiacetylene (HC$_{5}$N) toward hot molecular cores, observed with the Tidbinbilla 34 m radio telescope (DSS-34). In a sample of 79 hot molecular cores, HC$_{5}$N was detected towards 35. These results are counter to the expectation that long chain cyanopolyynes, such as HC$_{5}$N, are not typically found in hot molecular cores, unlike their shorter chain counterpart HC$_{3}$N. However it is consistent with recent models which suggest HC$_{5}$N may exist for a limited period during the evolution of hot molecular cores.

  20. Hc-fau, a novel gene regulating diapause in the nematode parasite Haemonchus contortus.

    Science.gov (United States)

    Yan, Baolong; Guo, Xiaolu; Zhou, Qianjin; Yang, Yi; Chen, Xueqiu; Sun, Weiwei; Du, Aifang

    2014-10-01

    Diapause induced in the early fourth stage of Haemonchus contortus is a strategy to adapt this nematode to hostile environmental conditions. In this study, we identified a new gene, Hc-fau, a homologue of human fau and Caenorhabditis elegans Ce-rps30. Hc-fau encodes two proteins through alternative RNA splicing, Hc-FAUA and Hc-FAUB, consisting of 130 and 107 amino acids, respectively. Hc-FAU possesses a diverged ubiquitin-like (UBiL) protein domain and a conserved ribosome protein S30 domain. The protein is ubiquitously expressed, except in the gonad. However Hc-fau transcripts decrease significantly in diapausing L4s of H. contortus. In C. elegans, knockdown of Ce-rps30 confers an extended lifespan, increased lipid storage in the intestine and shortened body length. These morphological characteristics are comparable with dauer larvae of C. elegans, in which the gonad is condensed considerably. In contrast, a shortened lifespan is observed in C. elegans over-expressing Hc-faua, and especially Hc-faub, with hatching failure detected. The genes of insulin/IGF-1 signalling (IIS), TGF-β, cGMP, dafachronic acid (DA), apoptosis (AP) and fatty acids (FA) metabolism are all down-regulated in Ce-rps30RNAi (RNA interference) worms, except for akt-1 and daf-16. However, daf-16 up-regulation is inconsistent with its target gene down-regulation and the result from a heat stress assay in these worms. Daf-16 RNAi conducted in Ce-rps30 (tm6034/nt1) mutants failed to rescue the worms. The S30 domain stays in the nucleus, while UBiL accumulates in the cytoplasm. Compared with Hc-FAUA, results of UBiL domain and S30 domain over-expression indicate synergism between UBiL and S30 in regulating lifespan and reproduction. These results suggest the potential functions of Hc-fau in regulating larval diapause in H.contortus.

  1. Comparison of the mutagenicity of exhaust emissions from motor vehicles using leaded and unleaded gasoline as fuel.

    Science.gov (United States)

    Yuan, D; Zhou, W; Ye, S H

    1999-06-01

    While unleaded gasoline has the advantage of eliminating lead from automobile exhaust, its potential to reduce the exhaust gas and particles, merits further examination. In the present studies, the concentrations of hydrocarbons (HC) and carbon mono-oxides (CO) in emissions were analyzed on Santana engine Dynamometer under a standard test cycle, and total exhaust particles were collected from engines using leaded and unleaded gasoline. It was found that unleaded gasoline reduced the emissions of CO and HC, and decreased the quantity of vehicle exhaust particulate matters by 60%. With the unleaded gasoline, only 23 kinds of organic substances, adsorbed in the particles, were identified by gas chromatography/mass spectrometer (GC/MS) while 32 components were detected using the leaded gasoline. The results of in vitro Salmonella/microsomal test and micronucleus induction assay in CHL cells indicated that both types of gasoline increased the number of histidine-independent colonies and the frequencies of micronucleus induction; no significant difference was found in their mutagenicity.

  2. Study of the origin of polycyclic aromatic hydrocarbons in water of Lake Baikal

    Science.gov (United States)

    Semenova, M. Yu.; Snytko, V. A.; Marinaite, I. I.

    2017-06-01

    The concentration of polycyclic aromatic hydrocarbons in the water of Lake Baikal is estimated. The published data on the composition of polycyclic aromatic hydrocarbons in industrial and communal emissions and in crude oils are analyzed. Anthropogenic sources of lake water contamination are revealed. It is concluded that polycyclic aromatic hydrocarbons enter the lake as a result of natural oil release.

  3. Survey of cotton (Gossypium sp.) for non-polar, extractable hydrocarbons for use as petrochemicals and liquid fuels

    Science.gov (United States)

    An ontogenetic study of a commercial cotton cultivar (FiberMax 1320), grown dryland, revealed that the dry weight (DW) of leaves reached a maximum at the 1st flower stage, and then declined as bolls opened. However, % pentane soluble hydrocarbon (HC) yield continued to increase throughout the growi...

  4. Optimization of Fuel Consumption and Emissions for Auxiliary Power Unit Based on Multi-Objective Optimization Model

    Directory of Open Access Journals (Sweden)

    Yongpeng Shen

    2016-02-01

    Full Text Available Auxiliary power units (APUs are widely used for electric power generation in various types of electric vehicles, improvements in fuel economy and emissions of these vehicles directly depend on the operating point of the APUs. In order to balance the conflicting goals of fuel consumption and emissions reduction in the process of operating point choice, the APU operating point optimization problem is formulated as a constrained multi-objective optimization problem (CMOP firstly. The four competing objectives of this CMOP are fuel-electricity conversion cost, hydrocarbon (HC emissions, carbon monoxide (CO emissions and nitric oxide (NO x emissions. Then, the multi-objective particle swarm optimization (MOPSO algorithm and weighted metric decision making method are employed to solve the APU operating point multi-objective optimization model. Finally, bench experiments under New European driving cycle (NEDC, Federal test procedure (FTP and high way fuel economy test (HWFET driving cycles show that, compared with the results of the traditional fuel consumption single-objective optimization approach, the proposed multi-objective optimization approach shows significant improvements in emissions performance, at the expense of a slight drop in fuel efficiency.

  5. Influences of Fuel Additive, Crude Palm and Waste Cooking Oil on Emission Characteristics of Small Diesel Engine

    Science.gov (United States)

    Khalid, Amir; Jaat, Norrizam; Manshoor, Bukhari; Zaman, Izzuddin; Sapit, Azwan; Razali, Azahari; Basharie, Mariam

    2017-08-01

    Major research has been conducted on the use of input products, such as rapeseed, canola, soybean, sunflower oil, waste cooking oil (WCO), crude palm oil (CPO) and crude jatropha oil as alternative fuels. Biodiesel is renewable, biodegradable and oxygenated, where it can be easily adopted by current existing conventional diesel engine without any major modification of the engine. To meet the future performance and emission regulations, is urged to improve the performance and exhaust emissions from biodiesel fuels. Hence, further investigation have been carried out on the emission characteristics of small diesel engine that fuelled by variant blending ratio of WCO and CPO with booster additive. For each of the biodiesel blends ratio from 5 to 15 percent volume which are WCO5, WCO10 and WCO15 for WCO biodiesel and CPO5, CPO10 and CPO15 for CPO biodiesel. The exhaust emissions were measured at engine speeds varied at 2000 rpm and 2500 rpm with different booster additive volume DRA (biodiesel without additive), DRB (0.2 ml) and DRC (0.4 ml). Emissions characteristics that had been measured were Hydrocarbon (HC), Carbon Monoxide (CO), Carbon Dioxide (CO2), Nitrogen Oxide (NOx), and smoke opacity. The results showed that increased of blending ratio with booster additive volume significantly decreased the CO emission, while increased in NOx and CO2 due to changes of fuel characteristics in biodiesel fuel blends.

  6. Improving the performance and emission characteristics of a single cylinder diesel engine having reentrant combustion chamber using diesel and Jatropha methyl esters.

    Science.gov (United States)

    Premnath, S; Devaradjane, G

    2015-11-01

    The emissions from the Compression ignition (CI) engines introduce toxicity to the atmosphere. The undesirable carbon deposits from these engines are realized in the nearby static or dynamic systems such as vehicles, inhabitants, etc. The objective of this research work is to improve the performance and emission characteristics of a diesel engine in the modified re-entrant combustion chamber using a diesel and Jatropha methyl ester blend (J20) at three different injection pressures. From the literature, it is revealed that the shape of the combustion chamber and the fuel injection pressure have an impact on the performance and emission parameters of the CI engine. In this work, a re-entrant combustion chamber with three different fuel injection pressures (200, 220 and 240bars) has been used in the place of the conventional hemispherical combustion chamber for diesel and J20. From the experimental results, it is found that the re-entrant chamber improves the brake thermal efficiency of diesel and J20 in all the tested conditions. It is also found that the 20% blend of Jatropha methyl ester showed 4% improvement in the brake thermal efficiency in the re-entrant chamber at the maximum injection pressure. Environmental safety directly relates to the reduction in the undesirable effects on both living and non-living things. Currently environmental pollution is of major concern. Even with the stringent emission norms new methods are required to reduce the harmful effects from automobiles. The toxicity of carbon monoxide (CO) is well known. In the re-entrant combustion chamber, the amount of CO emission is reduced by 26% when compared with the conventional fuel operation of the engine. Moreover, the amount of smoke is reduced by 24% and hydrocarbons (HC) emission by 24%. Thus, the modified re-entrant combustion chamber reduces harmful pollutants such as unburned HC and CO as well as toxic smoke emissions.

  7. Hydrocarbons in coastal sediments from the Mediterranean sea (Gulf of Fos area, France).

    Science.gov (United States)

    Mille, Gilbert; Asia, Laurence; Guiliano, Michel; Malleret, Laure; Doumenq, Pierre

    2007-05-01

    Sedimentary hydrocarbons have been studied quantitatively and qualitatively in 11 coastal stations located in the Gulf of Fos (French Mediterranean coast). Hydrocarbon levels ranged from 10 to 260 mg kg(-1) sed. dry weight. A new parameter "NAR" (Natural n-alkane ratio) is proposed to evaluate the contribution of terrestrial inputs of hydrocarbons in the sediments. The origins of hydrocarbons are multiple: terrestrial inputs, biogenic, pyrolytic (industry emissions mainly steel and iron industries, ship and road traffic). Generally, the main source of contamination is not petroleum. Several ratios between parent polycyclic aromatic hydrocarbons show that the sources of hydrocarbons in the sediments are generally much more pyrolytic than petrogenic.

  8. 北京市机动车尾气排放因子研究%Emission Factors of Vehicle Exhaust in Beijing

    Institute of Scientific and Technical Information of China (English)

    樊守彬; 田灵娣; 张东旭; 曲松

    2015-01-01

    通过调研北京市机动车车型构成﹑车辆行驶工况﹑环境温度﹑油品品质等基础数据,利用 COPERT Ⅳ模型计算了机动车尾气中 CO﹑ NOx﹑ HC 和 PM 的排放因子.应用车载测试系统对典型轻型汽油客车和柴油货车的实际道路排放因子进行测量,并将测量结果与模型计算结果对比,结果发现国Ⅳ标准下,轻型汽油客车的 CO 排放因子的实测数据是模型数据的0.96倍,NOx 的实测数据是模型数据的0.64倍,HC 的实测数据是模型数据的4.89倍.对于国Ⅲ排放标准的柴油货车,轻型﹑中型和重型货车的 CO 排放因子,实测数据分别是模型数据的1.61﹑1.07和1.76倍,NOx 排放因子的实测数据是模型数据的1.04﹑1.21和1.18倍,HC 排放因子的实测数据是模型数据的3.75﹑1.84和1.47倍,PM 排放因子则为模型数据是实测数据的1.31﹑3.42和6.42倍.%Based on the investigation of basic data such as vehicle type composition, driving conditions, ambient temperature and oil quality, etc. , emission factors of vehicle exhaust pollutants including carbon monoxide(CO), nitrogen oxides(NOx ), hydrocarbons (HC) and particulate matter(PM) were calculated using COPERT Ⅳ model. Emission factors of typical gasoline passenger cars and diesel trucks were measured using on-board measurement system on actual road. The measured and modeled emission factors were compared and the results showed that: the measured emission factors of CO, NOx and HC were 0. 96, 0. 64 and 4. 89 times of the modeled data for passenger cars conforming to the national Ⅳ emission standard. For the light, medium and heavy diesel trucks conforming to the national Ⅲ emission standard, the measured data of CO emission factors were 1. 61, 1. 07 and 1. 76 times of the modeled data, respectively, the measured data of NOx emission factors were 1. 04, 1. 21 and 1. 18 times of the modeled data, and the measured data of HC emission factors were 3. 75, 1. 84 and 1. 47

  9. Effect of HC/NOx ratio on the real refractive indices of secondary organic aerosol generated from photooxidation of limonene and α-pinene

    Science.gov (United States)

    Kim, H.; Barkey, B.; Paulson, S. E.

    2011-12-01

    The refractive index is the fundamental property controlling aerosol optical properties. The real refractive indices (mr) of secondary organic aerosols (SOA) generated from the photooxidation of limonene and α-pinene using different HC/NOx ratios are presented. Limonene and α-pinene are estimated to account for about 16 % and 25 % of global monoterpene emissions. Although the limonene emission rate is lower than of α-pinene, it has much higher SOA yields presumabely because it is doubly unsaturated. Refractive indices were retrieved from polar nephelometer measurements using parallel and perpendicular polarized 532 nm light. Retrievals were performed with a genetic algorithm method using Mie-Lorenz scattering theory and measured particle size distributions. The absolute error associated with the mr retrieval is ± 0.03, and the instrument has sufficient sensitivity to achieve reliable retrievals for aerosol mass concentrations of about 20 μg/m3 with particles larger than about 100 nm in diameter. Examination of the limonene SOA data suggests the most important factor controlling the refractive indexes the particle size, which in turn is influenced by the HC/NOx ratio; the refractive index is much less sensitive to the aerosol mass concentration or aerosol aging. The refractive index ranges from1.38 to 1.56 for limonene and from 1.37 to 1.51 for α-pinene, and generally decreases as the HC/NOx ratio increases (6.3 - 33 and 8.1 - 33 for limonene and α-pinene). Our data show that particle diameter is related to the aerosol refractive index; for limonene, as the HC/NOx ratio decreases, the size of particles increases (150 - 310 nm) and mrs increase from about 1.38 to a maximum of about 1.56. α-Pinene has the same trend for mrs; as the HC/NOx ratio decreases, the maximum size of particles increases (100 - 270 nm) and mrs increases from about 1.37 to a maximum of about 1.52. These results give suggest that chemical components controlling the size of SOA are a

  10. Nucleate pool boiling heat transfer coefficients of pure HFC134a, H&c, HC600a and their binary and ternary mixtures

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Zhaohu; Gong, Maoqiong; Li, Zhijian; Wu, Jianfeng [Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing (China)

    2007-01-15

    An experimental test rig for study on the pooling-boiling heat transfer performance of pure and mixed refrigerants were designed and established. With this test system, the heat transfer coefficients (HTCs) of the nucleate boiling on a smooth flat surface were measured for pure fluids of HFC134a, HC290, HC600a and their binary and ternary mixtures. Extensive experimental measures were made for those pure and mixed refrigerants at different heat fluxes from 10kWm{sup -2} to 300kWm{sup -2} and different pressures from 0.2 to 0.6MPa. Comprehensive measured data are presented in this paper. From experimental results, these binary mixtures and ternary mixtures show different heat transfer features according to their vapor-liquid phase equilibria behaviors. New heat transfer correlations were regressed from the measured data with average deviations within +/-15% for pure refrigerants and within +/-20% for mixtures. (author)

  11. Distribution of CCS and HC3N in L1147, an Early Phase Dark Cloud

    CERN Document Server

    Suzuki, Taiki; Hirota, Tomoya

    2014-01-01

    We used the Nobeyama 45 m radio telescope to reveal spatial distributions of CCS and HC$_3$N in L1147, one of carbon-chain producing regions (CCPRs) candidates, where carbon-chain molecules are dominant rather than NH$_3$. We found that three cores (two CCS cores and one HC$_3$N core) exist along the NE-SW filament traced by the 850 micron dust continuum, which are away from a Very Low Luminosity Object (VeLLO - a source that may turn into sub-stellar mass brown dwarf). The column densities of CCS are 3-7x10$^{12}$ cm$^{-2}$ and those of HC$_3$N are 2-6x10$^{12}$ cm$^{-2}$, respectively, much lower than those previously reported towards other CCPRs. We also found that two CCS peaks are displaced from that of HC$_3$N. In order to interpret such interleaved distributions, we conducted chemical reaction network simulations, and found that slightly different gas densities could lead to large variation of CCS-to-HC$_3$N ratio in the early phase of dark cloud evolution. Such a chemical "variation" may be seen in ot...

  12. Initial analysis of the hemocyanin subunit type 1 (Hc1 gene) from Locusta migratoria manilensis.

    Science.gov (United States)

    Yin, Hong; Guan, Ni; Dong, Lijun; Yue, Qiaoyun; Yin, Xiangchu; Zhang, Daochuan

    2012-03-01

    Hemocyanins are copper-containing (Cu(+)) proteins that transport oxygen in many arthropods hemolymph. We characterized Hc1 gene from the grasshopper species Locusta migratoria manilensis. In particular, we cloned and sequenced the corresponding cDNAs and studied their expression at different developmental stages. The cDNA of Hc1 gene (GenBank accession no.:HQ213937) is 2271 bp in length and the open reading frame is 2016 bp, which encodes a 672 amino acids protein with a calculated molecular mass of 77.9 kD and the isoelectric point of 6.06. Sequence alignment analysis result showed that this gene shares 94.7% identity with Schistocerca americana EHP. In addition, analysis of quantitative RT-PCR indicated that, LmiHc1 was expressed in the embyro (24, 39, 62, 86, 144, and 193 h after hatch), nymphs (1st instar, 2nd instar, 3rd instar, 4th instar and 5th instar) and in adult. These results showed that Hc1 plays an important role in grasshopper, which may be related to an enhanced oxygen supply. Phylogenetic analysis of insecta based on Hc1 are basically consistent with the morphology.

  13. Structural basis of TRPA1 inhibition by HC-030031 utilizing species-specific differences.

    Science.gov (United States)

    Gupta, Rupali; Saito, Shigeru; Mori, Yoshiharu; Itoh, Satoru G; Okumura, Hisashi; Tominaga, Makoto

    2016-11-22

    Pain is a harmful sensation that arises from noxious stimuli. Transient receptor potential ankyrin 1 (TRPA1) is one target for studying pain mechanisms. TRPA1 is activated by various stimuli such as noxious cold, pungent natural products and environmental irritants. Since TRPA1 is an attractive target for pain therapy, a few TRPA1 antagonists have been developed and some function as analgesic agents. The responses of TRPA1 to agonists and antagonists vary among species and these species differences have been utilized to identify the structural basis of activation and inhibition mechanisms. The TRPA1 antagonist HC-030031 (HC) failed to inhibit frog TRPA1 (fTRPA1) and zebrafish TRPA1 activity induced by cinnamaldehyde (CA), but did inhibit human TRPA1 (hTRPA1) in a heterologous expression system. Chimeric studies between fTRPA1 and hTRPA1, as well as analyses using point mutants, revealed that a single amino acid residue (N855 in hTRPA1) significantly contributes to the inhibitory action of HC. Moreover, the N855 residue and the C-terminus region exhibited synergistic effects on the inhibition by HC. Molecular dynamics simulation suggested that HC stably binds to hTRPA1-N855. These findings provide novel insights into the structure-function relationship of TRPA1 and could lead to the development of more effective analgesics targeted to TRPA1.

  14. Novel Photocatalytic Reactor Development for Removal of Hydrocarbons from Water

    Directory of Open Access Journals (Sweden)

    Morgan Adams

    2008-01-01

    Full Text Available Hydrocarbons contamination of the marine environment generated by the offshore oil and gas industry is generated from a number of sources including oil contaminated drill cuttings and produced waters. The removal of hydrocarbons from both these sources is one of the most significant challenges facing this sector as it moves towards zero emissions. The application of a number of techniques which have been used to successfully destroy hydrocarbons in produced water and waste water effluents has previously been reported. This paper reports the application of semiconductor photocatalysis as a final polishing step for the removal of hydrocarbons from two waste effluent sources. Two reactor concepts were considered: a simple flat plate immobilised film unit, and a new rotating drum photocatalytic reactor. Both units proved to be effective in removing residual hydrocarbons from the effluent with the drum reactor reducing the hydrocarbon content by 90% under 10 minutes.

  15. Potential benefits of solar reflective car shells: cooler cabins, fuel savings and emission reductions

    Energy Technology Data Exchange (ETDEWEB)

    Levinson, Ronnen; Pan, Heng; Ban-Weiss, George; Rosado, Pablo; Paolini, Riccardo; Akbari, Hashem

    2011-05-11

    Abstract: Vehicle thermal loads and air conditioning ancillary loads are strongly influenced by the absorption of solar energy. The adoption of solar reflective coatings for opaque surfaces of the vehicle shell can decrease the ?soak? temperature of the air in the cabin of a vehicle parked in the sun, potentially reducing the vehicle?s ancillary load and improving its fuel economy by permitting the use of a smaller air conditioner. An experimental comparison of otherwise identical black and silver compact sedans indicated that increasing the solar reflectance (?) of the car?s shell by about 0.5 lowered the soak temperature of breath-level air by about 5?6?C. Thermal analysis predicts that the air conditioning capacity required to cool the cabin air in the silver car to 25?C within 30min is 13percent less than that required in the black car. Assuming that potential reductions in AC capacity and engine ancillary load scale linearly with increase in shell solar reflectance, ADVISOR simulations of the SC03 driving cycle indicate that substituting a typical cool-colored shell (?=0.35) for a black shell (?=0.05) would reduce fuel consumption by 0.12L per 100km (1.1percent), increasing fuel economy by 0.10kmL?1 [0.24mpg] (1.1percent). It would also decrease carbon dioxide (CO2) emissions by 2.7gkm?1 (1.1percent), nitrogen oxide (NOx) emissions by 5.4mgkm?1 (0.44percent), carbon monoxide (CO) emissions by 17mgkm?1 (0.43percent), and hydrocarbon (HC) emissions by 4.1mgkm?1 (0.37percent). Selecting a typical white or silver shell (?=0.60) instead of a black shell would lower fuel consumption by 0.21L per 100km (1.9percent), raising fuel economy by 0.19kmL?1 [0.44mpg] (2.0percent). It would also decrease CO2 emissions by 4.9gkm?1 (1.9percent), NOx emissions by 9.9mgkm?1 (0.80percent), CO emissions by 31mgkm?1 (0.79percent), and HC emissions by 7.4mgkm?1 (0.67percent). Our simulations may underestimate emission reductions because emissions in standardized driving cycles are

  16. Attempts to minimize nitrogen oxide emission from diesel engine by using antioxidant-treated diesel-biodiesel blend.

    Science.gov (United States)

    Rashedul, Hasan Khondakar; Kalam, Md Abdul; Masjuki, Haji Hassan; Teoh, Yew Heng; How, Heoy Geok; Monirul, Islam Mohammad; Imdadul, Hassan Kazi

    2017-02-23

    The study represents a comprehensive analysis of engine exhaust emission variation from a compression ignition (CI) diesel engine fueled with diesel-biodiesel blends. Biodiesel used in this investigation was produced through transesterification procedure from Moringa oleifera oil. A single cylinder, four-stroke, water-cooled, naturally aspirated diesel engine was used for this purpose. The pollutants from the exhaust of the engine that are monitored in this study are nitrogen oxide (NO), carbon monoxide (CO), hydrocarbon (HC), and smoke opacity. Engine combustion and performance parameters are also measured together with exhaust emission data. Some researchers have reported that the reason for higher NO emission of biodiesel is higher prompt NO formation. The use of antioxidant-treated biodiesel in a diesel engine is a promising approach because antioxidants reduce the formation of free radicals, which are responsible for the formation of prompt NO during combustion. Two different antioxidant additives namely 2,6-di-tert-butyl-4-methylphenol (BHT) and 2,2'-methylenebis(4-methyl-6-tert-butylphenol) (MBEBP) were individually dissolved at a concentration of 1% by volume in MB30 (30% moringa biodiesel with 70% diesel) fuel blend to investigate and compare NO as well as other emissions. The result shows that both antioxidants reduced NO emission significantly; however, HC, CO, and smoke were found slightly higher compared to pure biodiesel blends, but not more than the baseline fuel diesel. The result also shows that both antioxidants were quite effective in reducing peak heat release rate (HRR) and brake-specific fuel consumption (BSFC) as well as improving brake thermal efficiency (BTE) and oxidation stability. Based on this study, antioxidant-treated M. oleifera biodiesel blend (MB30) can be used as a very promising alternative source of fuel in diesel engine without any modifications.

  17. 我国8种市售蚊香燃烧烟气中多环芳烃的排放特征%Emission Characteristics of Polycyclic Aromatic Hydrocarbons in the Smoke from Eight Mosquito Coils in Chinese Market

    Institute of Scientific and Technical Information of China (English)

    周宏仓; 宋园园; 陆建刚; 李红双; 马嫣; 蔡华侠; 赵晓莉

    2009-01-01

    利用GC-MS对8种具有代表性的市售蚊香燃烧烟气中16种列入美国环境保护署(US EPA)优先控制的多环芳烃(PAHs)进行分析. 结果表明:有烟蚊香烟气中16种优先控制的PAHs均有检出(6号蚊香除外),排放因子较大的化合物主要有萘、苊、二氢苊、菲和荧蒽;无烟蚊香烟气中仅检出10~11种,排放因子最大的化合物是菲,其次为萘;各种蚊香烟气中PAHs均以2~3环化合物为主,约占排放量的83.3%~98.0%. 同无烟蚊香相比,有烟蚊香烟气中PAHs的排放量较大,毒性也较高. 根据烟气中PAHs排放因子估算出一盘蚊香燃烧后烟气中苯并[a]芘排放量相当于燃烧4支香烟,PAHs排放量相当于燃烧8支香烟;蚊香燃烧后室内空气中ρ(PAHs)高达 1 486.60ng/m~3,其中ρ(苯并[a]芘)为8.07ng/m~3,超过其 (GB/T18883─2002)中的日均限值.%The GC-MS technique was applied to analyze 16 US EPA-recommend priority-controlled polycyclic aromatic hydrocarbons (PAHs) from the smoke of eight mosquito coils in Chinese market. The results showed that all 16 priority-controlled PAHs were detected in the smoke of all smoking mosquito coils with the exception of coil No.6. The emissions were characterized by the predominance of Nap, AcPy, AcP, Phe and FluA. Only 10-11 PAHs were detected in the smoke from smokeless mosquito coils, with the main contributors including Phe and NaP. Among all the coils, the concentration distribution of PAHs was dominated by 2-ringed and 3-ringed PAHs, accounting for about 83.3%-98.0%. It can be seen that the amount of total PAHs emission and total toxic equivalent of PAHs in the smoke from smoking mosquito coils is much higher than that from smokeless mosquito coils. Based on emission factors in the smoke, burning one mosquito coil would release the same amount of BaP as burning 4 cigarettes, and the total amount of PAHs emission from burning one mosquito coil would be as high as that released from burning 8 cigarettes

  18. Collisional excitation of HC3N by para- and ortho-H2

    CERN Document Server

    Faure, A; Wiesenfeld, L

    2016-01-01

    New calculations for rotational excitation of cyanoacetylene by collisions with hydrogen molecules are performed to include the lowest 38 rotational levels of HC3N and kinetic temperatures to 300 K. Calculations are based on the interaction potential of Wernli et al. A&A, 464, 1147 (2007) whose accuracy is checked against spectroscopic measurements of the HC3N-H2 complex. The quantum coupled-channel approach is employed and complemented by quasi-classical trajectory calculations. Rate coefficients for ortho-H2 are provided for the first time. Hyperfine resolved rate coefficients are also deduced. Collisional propensity rules are discussed and comparisons between quantum and classical rate coefficients are presented. This collisional data should prove useful in interpreting HC3N observations in the cold and warm ISM, as well as in protoplanetary disks.

  19. Finite element analysis of hypervelocity impact behaviour of CFRP-Al/HC sandwich panel

    Science.gov (United States)

    Phadnis, Vaibhav A.; Silberschmidt, Vadim V.

    2015-09-01

    The mechanical response of CFRP-Al/HC (carbon fibre-reinforced/epoxy composite face sheets with Al honeycomb core) sandwich panels to hyper-velocity impact (up to 1 km/s) is studied using a finite-element model developed in ABAQUS/Explicit. The intraply damage of CFRP face sheets is analysed by mean of a user-defined material model (VUMAT) employing a combination of Hashin and Puck criteria, delamination modelled using cohesive-zone elements. The damaged Al/HC core is assessed on the basis of a Johnson Cook dynamic failure model while its hydrodynamic response is captured using the Mie-Gruneisen equation of state. The results obtained with the developed finite-element model showed a reasonable correlation to experimental damage patterns. The surface peeling of both face sheets was evident, with a significant delamination around the impact location accompanied by crushing HC core.

  20. Hypervelocity Impact Behaviour of CFRP-A1/HC Sandwich Panel: Finite-Element Studies

    Science.gov (United States)

    Phadnis, Vaibhav A.; Roy, Anish; Silberschmidt, Vadim V.

    2014-06-01

    The mechanical response of CFRP-Al/HC (carbon fibre- reinforced/epoxy composite face sheets with Al honeycomb core) sandwich panels to hyper-velocity impact ( 1 km/s) is studied using a finite-element model developed in ABAQUS/Explicit. The intraply damage of CFRP face sheets is analysed by the means of a user-defined material model (VUMAT) employing a combination of Hashin and Puck criteria and delamination is modelled using cohesive-zone elements. The damage of Al/HC core is assessed on the basis of a Johnson-Cook dynamic failure model while its hydrodynamic response is captured using the Mie- Gruneisen equation of state. The results obtained with the developed finite-element model showed a reasonable correlation to experimental damage patterns. The surface peeling of both face sheets was evident, with a significant delamination around the impact location accompanied by crushing of HC core.

  1. Finite element analysis of hypervelocity impact behaviour of CFRP-Al/HC sandwich panel

    Directory of Open Access Journals (Sweden)

    Phadnis Vaibhav A.

    2015-01-01

    Full Text Available The mechanical response of CFRP-Al/HC (carbon fibre-reinforced/epoxy composite face sheets with Al honeycomb core sandwich panels to hyper-velocity impact (up to 1 km/s is studied using a finite-element model developed in ABAQUS/Explicit. The intraply damage of CFRP face sheets is analysed by mean of a user-defined material model (VUMAT employing a combination of Hashin and Puck criteria, delamination modelled using cohesive-zone elements. The damaged Al/HC core is assessed on the basis of a Johnson Cook dynamic failure model while its hydrodynamic response is captured using the Mie-Gruneisen equation of state. The results obtained with the developed finite-element model showed a reasonable correlation to experimental damage patterns. The surface peeling of both face sheets was evident, with a significant delamination around the impact location accompanied by crushing HC core.

  2. EFFECT OF COPPER ON THE HOT PLASTICITY OF 304HC STAINLESS STEEL

    Institute of Scientific and Technical Information of China (English)

    G.Z. Cui; H.S. Di; G.D. Wang; X.H. Liu

    2005-01-01

    The plasticity map of 304HC stainless steel was determined by using tensile and compressive test. The effect of Cu on the hot plasticity of 304HC stainless steel was analyzed. The microstructure, inclusion and fracture surface were studied by using the method of optical microscopy, SEM,EDS and EPMA. The results showed that Cu has effect on the hot plasticity and the hotplasticity of 304HC stainless steel decrease with the increase of Cu content. The deformation temperature also hasmuch effect on the hot plasticity, the suitable deformation temperature are 1100-1200℃.The reason is that the brittle compounds were precipitated from austenite during cooling. These brittle compounds are Cu2S, Cu2O and PbCl etc.

  3. 玉米矮花叶病毒HC-Pro的纯化及抗血清制备%PURIFICATION AND ANTISERUM PREPARATION OF MAIZE DWARF MOSAIC VIRUS HC-Pro

    Institute of Scientific and Technical Information of China (English)

    李向东; 范在丰; 李怀方; 裘维蕃

    2001-01-01

    本实验提纯了玉米矮花叶病毒(MDMV)的辅助成份-蛋白酶(HC-Pro),并制备了其抗血清.MDMV HC-Pro的分子量约为57 kD,提纯产量为0.3 mg/100g病叶.琼脂免疫双扩散测定证明MDMV HC-Pro抗血清的效价为1:16;微量免疫沉淀法测定时其效价为1:1024.该抗血清只与MDMV HC-Pro有明显的反应,与健康玉米汁液和MDMV无反应.MDMV HC-Pro抗血清可以专化性地抑制HC-Pro的蚜传活性.

  4. Organic metamorphism in the California petroleum basins; Chapter B, Insights from extractable bitumen and saturated hydrocarbons

    Science.gov (United States)

    Price, Leigh C.

    2000-01-01

    Seventy-five shales from the Los Angeles, Ventura, and Southern San Joaquin Valley Basins were extracted and analyzed. Samples were chosen on the basis of ROCK-EVAL analyses of a much larger sample base. The samples ranged in burial temperatures from 40 ? to 220 ? C, and contained hydrogen-poor to hydrogen-rich organic matter (OM), based on OM visual typing and a correlation of elemental kerogen hydrogen to carbon ratios with ROCK-EVAL hydrogen indices. By extractable bitumen measurements, rocks with hydrogen- poor OM in the Los Angeles Basin began mainstage hydrocarbon (HC) generation by 90 ? C. The HC concentrations maximized by 165 ? C, and beyond 165 ? C, HC and bitumen concentrations and ROCK-EVAL hydrogen indices all began decreasing to low values reached by 220 ? C, where HC generation was largely complete. Rocks with hydrogen-poor OM in the Southern San Joaquin Valley Basin commenced mainstage HC generation at 135 ? C and HC concentrations maximized by 180 ? C. Above 180 ? C, HC and bitumen concentrations and ROCK-EVAL hydrogen indices all decreased to low values reached by 214 ? C, again the process of HC generation being largely complete. In both cases, bell-shaped HC-generation curves were present versus depth (burial temperature). Mainstage HC generation had not yet begun in Ventura Basin rocks with hydrogen-poor OM by 140 ? C. The apparent lower temperature for initiation of mainstage generation in the Los Angeles Basin is attributed to very recent cooling in that basin from meteoric-water flow. Thus, HC generation there most probably occurred at higher burial temperatures. In contrast, mainstage HC generation, and all aspects of organic metamorphism, were strongly suppressed in rocks with hydrogen-rich OM at temperatures as high as 198 ? C. For example, shales from the Wilmington field (Los Angeles Basin) from 180 ? to 198 ? C retained ROCK-EVAL hydrogen indices of 550- 700 and had saturated-HC coefficients of only 4-15 mg/g organic carbon. The rocks

  5. THE STRUCTURE, ORIGIN, AND EVOLUTION OF INTERSTELLAR HYDROCARBON GRAINS

    Energy Technology Data Exchange (ETDEWEB)

    Chiar, J. E.; Ricca, A. [SETI Institute, Carl Sagan Center, 189 Bernardo Avenue, Mountain View, CA 94043 (United States); Tielens, A. G. G. M. [Leiden Observatory, P.O. Box 9513, NL-2300 RA Leiden (Netherlands); Adamson, A. J., E-mail: jchiar@seti.org, E-mail: Alessandra.Ricca@1.nasa.gov, E-mail: tielens@strw.leidenuniv.nl, E-mail: aadamson@gemini.edu [Gemini Observatory, Northern Operations Center, 670 North A' ohoku Place, Hilo, HI 96729 (United States)

    2013-06-10

    Many materials have been considered for the carrier of the hydrocarbon absorption bands observed in the diffuse interstellar medium (ISM). In order to refine the model for ISM hydrocarbon grains, we analyze the observed aromatic (3.28, 6.2 {mu}m) and aliphatic (3.4 {mu}m) hydrocarbon absorption features in the diffuse ISM along the line of sight toward the Galactic center Quintuplet Cluster. Observationally, sp {sup 2} bonds can be measured in astronomical spectra using the 6.2 {mu}m CC aromatic stretch feature, whereas the 3.4 {mu}m aliphatic feature can be used to quantify the fraction of sp {sup 3} bonds. The fractional abundance of these components allows us to place the Galactic diffuse ISM hydrocarbons on a ternary phase diagram. We conclude that the Galactic hydrocarbon dust has, on average, a low H/C ratio and sp {sup 3} content and is highly aromatic. We have placed the results of our analysis within the context of the evolution of carbon dust in the ISM. We argue that interstellar carbon dust consists of a large core of aromatic carbon surrounded by a thin mantle of hydrogenated amorphous carbon (a-C:H), a structure that is a natural consequence of the processing of stardust grains in the ISM.

  6. Nonmethane hydrocarbon composition of urban and rural atmospheres

    Science.gov (United States)

    Sexton, Ken; Westberg, Hal

    Nonmethane hydrocarbons (NMHC) are not measured routinely at most ambient monitoring stations. Yet this type of information is required to evaluate existing control strategies aimed at achieving the National Ambient Air Quality Standard for O 3. This paper summarizes data from ambient air monitoring programs in seven urban centers (Houston, Philadelphia, Baltimore, Washington, D.C., Newark, Boston, Milwaukee,) and six rural areas in California, Wisconsin, Texas, Illinois, Maine and Florida. Gas Chromatographie analysis was used to identify individual C 2-C 10 HCs in more than 990 ambient air samples. Measurements in urban and rural areas are compared based on total and individual HC concentrations.

  7. EXPERIMENTAL INVESTIGATION OF COLD START EMISSIONS USING ELECTRICALLY HEATED CATALYSTS IN A SPARK IGNITION ENGINE

    Directory of Open Access Journals (Sweden)

    K. Bhaskar

    2010-12-01

    Full Text Available The population of spark-ignition vehicles in urban areas is very high and is increasing rapidly due to their convenience for short distance transportation. These vehicles are major sources of urban air pollution compared to vehicles with diesel engines. Catalytic converters are used to control their emissions but they attain their maximum conversion rates of about 80%¬–90% under optimum operating conditions and are not effective during cold start conditions. The objective of the present work is to demonstrate that an electrically heated catalyst (EHC in combination with a traditional converter can achieve the Low and Ultra Low Emission Vehicle (LEV, ULEV standards. Experiments were conducted to investigate the impact of various metal oxides in EHC and design parameters to reduce cold-start emissions of a multi-cylinder SI engine. It is observed that EHC reduces cold-start hydrocarbon and carbon monoxide emissions when used with an existing catalytic converter. The maximum CO and HC reductions were achieved with copper oxide as the catalyst in EHC with air injection of 80 lpm for 40 sec after cold start of the engine.

  8. Electronic spectra of linear HC$_5$H and cumulene carbene H$_2$C$_5$

    CERN Document Server

    Steglich, M; Maity, S; Nagy, A; Maier, J P

    2015-01-01

    The $1 ^3\\Sigma_u^- \\leftarrow X^3\\Sigma_g^-$ transition of linear HC$_5$H (A) has been observed in a neon matrix and gas phase. The assignment is based on mass-selective experiments, extrapolation of previous results of the longer HC$_{2n+1}$H homologues, and density functional and multi-state CASPT2 theoretical methods. Another band system starting at 303 nm in neon is assigned as the $1 ^1 A_1 \\leftarrow X ^1 A_1$ transition of the cumulene carbene pentatetraenylidene H$_2$C$_5$ (B).

  9. Aircraft gas turbine low-power emissions reduction technology program

    Science.gov (United States)

    Dodds, W. J.; Gleason, C. C.; Bahr, D. W.

    1978-01-01

    Advanced aircraft turbine engine combustor technology was used to reduce low-power emissions of carbon monoxide and unburned hydrocarbons to levels significantly lower than those which were achieved with current technology. Three combustor design concepts, which were designated as the hot-wall liner concept, the recuperative-cooled liner concept, and the catalyst converter concept, were evaluated in a series of CF6-50 engine size 40 degree-sector combustor rig tests. Twenty-one configurations were tested at operating conditions spanning the design condition which was an inlet temperature and pressure of 422 K and 304 kPa, a reference velocity of 23 m/s and a fuel-air-ration of 10.5 g/kg. At the design condition typical of aircraft turbine engine ground idle operation, the best configurations of all three concepts met the stringent emission goals which were 10, 1, and 4 g/kg for CO, HC, and Nox, respectively.

  10. An experimental investigation of exhaust emission from agricultural tractors

    Directory of Open Access Journals (Sweden)

    Rashid Gholami, Hekmat Rabbani, Ali Nejat Lorestani, Payam Javadikia, Farzad Jaliliantabar

    2013-01-01

    Full Text Available Agricultural machinery is an important source of emission of air pollutant in rural locations. Emissions of a specific tractor engine mainly depend on engine speed. Various driving methods and use of implements with different work capacities can affect the engine load. This study deals with the effects of types of tractors and operation conditions on engine emission. In this study two types of agricultural tractors (MF285 and U650 and some tillage implements such as centrifugal type spreader, boom type sprayer and rotary tiller were employed. Some of the exhausted gases from both tractors in each condition were measured such as, hydrocarbon (HC, carbon monoxide (CO, carbon dioxide (CO2, oxygen (O2 and nitrogen oxide (NO. Engine oil temperature was measured at every step for both types of tractors. Difference between steady-state condition and operation conditions was evaluated. The results showed all exhaust gases that measured and engine oil temperature at every operation conditions are higher than steady-state condition. A general conclusion of the work was that, using various implements and employing different types of tractors effect on engine emissions. The results of variance analysis showed all exhausted gases had a significant relationship with types of implements used at 1%. Also, all exhausted gases except CO had a significant relationship with types of tractors. A further conclusion was that NO emission increased as engine oil temperature increased. The final conclusion was about the difference between MF285 and U650; using U650 at operation conditions is better than MF285 in terms of pollution.

  11. An experimental investigation of exhaust emission from agricultural tractors

    Energy Technology Data Exchange (ETDEWEB)

    Gholami, Rashid; Rabbani, Hekmat; Lorestani, Ali Nejat; Javadikia, Payam; Jaliliantabar, Farzad [Mechanics of Agricultural Machinery Department, Razi University of Kermanshah (Iran, Islamic Republic of)

    2013-07-01

    Agricultural machinery is an important source of emission of air pollutant in rural locations. Emissions of a specific tractor engine mainly depend on engine speed. Various driving methods and use of implements with different work capacities can affect the engine load. This study deals with the effects of types of tractors and operation conditions on engine emission. In this study two types of agricultural tractors (MF285 and U650) and some tillage implements such as centrifugal type spreader, boom type sprayer and rotary tiller were employed. Some of the exhausted gases from both tractors in each condition were measured such as, hydrocarbon (HC), carbon monoxide (CO), carbon dioxide (CO2), oxygen (O2) and nitrogen oxide (NO). Engine oil temperature was measured at every step for both types of tractors. Difference between steady-state condition and operation conditions was evaluated. The results showed all exhaust gases that measured and engine oil temperature at every operation conditions are higher than steady-state condition. A general conclusion of the work was that, using various implements and employing different types of tractors effect on engine emissions. The results of variance analysis showed all exhausted gases had a significant relationship with types of implements used at 1%. Also, all exhausted gases except CO had a significant relationship with types of tractors. A further conclusion was that NO emission increased as engine oil temperature increased. The final conclusion was about the difference between MF285 and U650; using U650 at operation conditions is better than MF285 in terms of pollution.

  12. Integrating a macro emission model with a macroscopic traffic model

    NARCIS (Netherlands)

    Klunder, G.A.; Stelwagen, U.; Taale, H.

    2013-01-01

    This paper presents a macro emission module for macroscopic traffic models to be used for assessment of ITS and traffic management. It especially focuses on emission estimates for different intersection types. It provides emission values for CO, CO2, HC, NOx, and PM10. It is applied and validated fo

  13. Progress towards atomic vapor photonic microcells: Coherence and polarization relaxation measurements in coated and uncoated HC-PCF

    Science.gov (United States)

    Bradley, T. D.; McFerran, J. J.; Jouin, J.; Ilinova, E.; Thomas, P.; Benabid, F.

    2013-03-01

    We report a comparative study on dephasing mechanisms between inner core coated and uncoated sections of the same Kagome hypocycloid-shaped core hollow core photonic crystal fibers (HC-PCF) filled with rubidium vapor. The comparison is performed by measuring the atomic polarization relaxation and electromagnetically induced transparency (EIT) linewidth in Rb loaded polydimethylsiloxane (PDMS) inner wall coated and bare silica core Kagome HC-PCF. The measurements show a polarization relaxation time of 32μs in a PDMS coated Kagome HC-PCF and 24μs in uncoated Kagome HC-PCF. A minimum EIT linewidth of 6.2±0.8MHz is achieved in PDMS coated Kagome HC-PCF, and 8.3±0.9 MHz for the uncoated Kagome HC-PCF.

  14. Influence of ethanol-gasoline blended fuel on emission characteristics from a four-stroke motorcycle engine.

    Science.gov (United States)

    Jia, Li-Wei; Shen, Mei-Qing; Wang, Jun; Lin, Man-Qun

    2005-08-31

    Emission characteristics from a four-stroke motorcycle engine using 10% (v/v) ethanol-gasoline blended fuel (E10) were investigated at different driving modes on the chassis dynamometers. The results indicate that CO and HC emissions in the engine exhaust are lower with the operation of E10 as compared to the use of unleaded gasoline, whereas the effect of ethanol on NO(X) emission is not significant. Furthermore, species of both unburned hydrocarbons and their ramifications were analyzed by the combination of gas chromatography/mass spectrometry (GC/MS) and gas chromatography/flame ionization detection (GC/FID). This analysis shows that aromatic compounds (benzene, toluene, xylene isomers (o-xylene, m-xylene and p-xylene), ethyltoluene isomers (o-ethyltoluene, m-ethyltoluene and p-ethyltoluene) and trimethylbenzene isomers (1,2,3-trimethylbenzene, 1,2,4-trimethylbenzene and 1,3,5-trimethylbenzene)) and fatty group ones (ethylene, methane, acetaldehyde, ethanol, butene, pentane and hexane) are major compounds in motorcycle engine exhaust. It is found that the E10-fueled motorcycle engine produces more ethylene, acetaldehyde and ethanol emissions than unleaded gasoline engine does. The no significant reduction of aromatics is observed in the case of ethanol-gasoline blended fuel. The ethanol-gasoline blended fuel can somewhat improve emissions of the rest species.

  15. The emission analysis of an IDI diesel engine fueled with methyl ester of waste frying palm oil and its blends

    Energy Technology Data Exchange (ETDEWEB)

    Ozsezen, Ahmet Necati; Canakci, Mustafa [Department of Automotive Engineering Technology, Kocaeli University, 41380, Izmit (Turkey); Alternative Fuels R and D Center, Kocaeli University, 41275, Izmit (Turkey)

    2010-12-15

    In this study, the exhaust emissions of an unmodified diesel engine fueled with methyl ester of waste frying palm-oil (biodiesel) and its blends with petroleum based diesel fuel (PBDF) were investigated at the full load-variable speed condition. The relationships between the fuel properties and the air-fuel equivalence ratio, fuel line pressure, start of injection (SOI) timing, and ignition delay were also discussed to explain their effects on the emissions. The obtained test results were compared with the reference values which were determined by using PBDF. The results showed that when biodiesel was used in the test engine, the fuel line pressure increased while air-fuel equivalence ratio and ignition delay decreased. These behaviors affected the combustion phenomena of biodiesel which caused to reduction 57% in carbon monoxide (CO) emission, about 40% in unburned hydrocarbon (HC) emission and about 23% in smoke opacity when compared with PBDF. However, NO{sub x} and CO{sub 2} emissions of the biodiesel have showed different behaviors in terms of the engine speed. (author)

  16. LIKE IT ACID AND POOR: A STUDY OF ABIOTIC FACTORS INFLUENCING Streptococcus bovis HC5 GROWTH AND BACTERIOCIN PRODUCTION

    Directory of Open Access Journals (Sweden)

    Ana Andréa Teixeira Barbosa

    2015-04-01

    Full Text Available This study aimed to investigate the effect of pH, temperature, growth atmosphere and nutrient availability on bovicin HC5 production by Streptococcus bovis HC5. S. bovis HC5 grew well in complex and basal media under aerobic and anaerobic conditions, but greater bacteriocin yields were recovered from anaerobic cultures. Lactate production and glucose consumption increased if S. bovis HC5 cells were cultivated at pH 7.0 and at 45 ºC, but higher bovicin HC5 activity was recovered from cells grown in acidic conditions and at lower temperatures (39 ºC. Cultures maintained under continuous CO2 flow showed faster growth rates in basal media, but bacteriocin production was always higher if S. bovis was cultivated in anaerobic sealed tubes. These results suggest that acidic pH and anoxic conditions favor bovicin HC5 production by S. bovis HC5. S. bovis HC5 is a unique lactic acid bacterium in its ability to grow and produce high amounts of a potentially useful bacteriocin in simple media. Considering the constrains for bacteriocin production at commercial scale, it appears that bovicin HC5 production could be achieved at lower costs compared to other bacteriocins from lactic acid bacteria.

  17. Hydrocarbon occurrence in NW Africa's MSGBC area

    Energy Technology Data Exchange (ETDEWEB)

    Reymond, A.; Negroni, P.

    1989-06-01

    The MSGBC (Mauritania, Senegal, The Gambia, Guinea-Bissau, Guinea Conakry) coastal basin has evolved as a passive margin from Jurassic time up to the present following a period of poorly known rifting of Permian to Middle Jurassic age. Structural configuration of the Paleozoic series is documented by large outcrops and a good number of seismic sections. Based on previous exploration efforts that found significant hydrocarbon shows, a comprehensive study of this African basin's source rocks, maturation evolution and petroleum generation potential was undertaken. About 1,000 geochemical analyses of the Paleozoic, Cretaceous and Tertiary series identified good source rocks in the Cenomano-Turonian, Silurian, Senonian and Paleocene ages. The parameters used to identify and characterize source rock are: Total organic carbon content (TOC) in percent and source potential (in kg HC/t), representing the amount of hydrocarbon generated per ton of rock and determined by Rock-Eval pyrolysis.

  18. Oxygenated Derivatives of Hydrocarbons

    Science.gov (United States)

    For the book entitled “Insect Hydrocarbons: Biology, Biochemistry and Chemical Ecology”, this chapter presents a comprehensive review of the occurrence, structure and function of oxygenated derivatives of hydrocarbons. The book chapter focuses on the occurrence, structural identification and functi...

  19. Hydrocarbon Spectral Database

    Science.gov (United States)

    SRD 115 Hydrocarbon Spectral Database (Web, free access)   All of the rotational spectral lines observed and reported in the open literature for 91 hydrocarbon molecules have been tabulated. The isotopic molecular species, assigned quantum numbers, observed frequency, estimated measurement uncertainty and reference are given for each transition reported.

  20. Comparative study of regulated and unregulated gaseous emissions during NEDC in a light-duty diesel engine fuelled with Fischer Tropsch and biodiesel fuels

    Energy Technology Data Exchange (ETDEWEB)

    Bermudez, Vicente; Lujan, Jose M.; Pla, Benjamin; Linares, Waldemar G. [CMT-Motores Termicos, Universidad Politecnica de Valencia, Camino de Vera s/n, 46022 Valencia (Spain)

    2011-02-15

    In this study, regulated and unregulated gaseous emissions and fuel consumption with five different fuels were tested in a 4-cylinder, light-duty diesel EURO IV typically used for the automotive vehicles in Europe. Three different biodiesel fuels obtained from soybean oil, rapeseed oil and palm oil, a Fischer Tropsch fuel and an ultra low sulphur diesel were studied. The test used was the New European Driving Cycle (NEDC), this allowed tests to be carried out on an engine warmed up beforehand to avoid the effect of cold starts and several tests a day. Regulated emissions of NO{sub X}, CO, HC and CO{sub 2} were measured for each fuel. Unburned Hydrocarbon Speciation and formaldehyde were also measured in order to determine the maximum incremental reactivity (MIR) of the gaseous emissions. Pollutants were measured without the diesel oxidation catalyst (DOC) to gather data about raw emissions. When biodiesel was used, increases in regulated and unregulated emissions were observed and also significant increases in engine fuel consumption. The use of Fischer Tropsch fuel, however, caused lower regulated and unregulated emissions and fuel consumption than diesel. (author)

  1. HC-Pro silencing suppressor significantly alters the gene expression profile in tobacco leaves and flowers

    Directory of Open Access Journals (Sweden)

    Lehto Kirsi

    2011-04-01

    Full Text Available Abstract Background RNA silencing is used in plants as a major defence mechanism against invasive nucleic acids, such as viruses. Accordingly, plant viruses have evolved to produce counter defensive RNA-silencing suppressors (RSSs. These factors interfere in various ways with the RNA silencing machinery in cells, and thereby disturb the microRNA (miRNA mediated endogene regulation and induce developmental and morphological changes in plants. In this study we have explored these effects using previously characterized transgenic tobacco plants which constitutively express (under CaMV 35S promoter the helper component-proteinase (HC-Pro derived from a potyviral genome. The transcript levels of leaves and flowers of these plants were analysed using microarray techniques (Tobacco 4 × 44 k, Agilent. Results Over expression of HC-Pro RSS induced clear phenotypic changes both in growth rate and in leaf and flower morphology of the tobacco plants. The expression of 748 and 332 genes was significantly changed in the leaves and flowers, respectively, in the HC-Pro expressing transgenic plants. Interestingly, these transcriptome alterations in the HC-Pro expressing tobacco plants were similar as those previously detected in plants infected with ssRNA-viruses. Particularly, many defense-related and hormone-responsive genes (e.g. ethylene responsive transcription factor 1, ERF1 were differentially regulated in these plants. Also the expression of several stress-related genes, and genes related to cell wall modifications, protein processing, transcriptional regulation and photosynthesis were strongly altered. Moreover, genes regulating circadian cycle and flowering time were significantly altered, which may have induced a late flowering phenotype in HC-Pro expressing plants. The results also suggest that photosynthetic oxygen evolution, sugar metabolism and energy levels were significantly changed in these transgenic plants. Transcript levels of S

  2. HC-Pro silencing suppressor significantly alters the gene expression profile in tobacco leaves and flowers.

    Science.gov (United States)

    Soitamo, Arto J; Jada, Balaji; Lehto, Kirsi

    2011-04-20

    RNA silencing is used in plants as a major defence mechanism against invasive nucleic acids, such as viruses. Accordingly, plant viruses have evolved to produce counter defensive RNA-silencing suppressors (RSSs). These factors interfere in various ways with the RNA silencing machinery in cells, and thereby disturb the microRNA (miRNA) mediated endogene regulation and induce developmental and morphological changes in plants. In this study we have explored these effects using previously characterized transgenic tobacco plants which constitutively express (under CaMV 35S promoter) the helper component-proteinase (HC-Pro) derived from a potyviral genome. The transcript levels of leaves and flowers of these plants were analysed using microarray techniques (Tobacco 4 × 44 k, Agilent). Over expression of HC-Pro RSS induced clear phenotypic changes both in growth rate and in leaf and flower morphology of the tobacco plants. The expression of 748 and 332 genes was significantly changed in the leaves and flowers, respectively, in the HC-Pro expressing transgenic plants. Interestingly, these transcriptome alterations in the HC-Pro expressing tobacco plants were similar as those previously detected in plants infected with ssRNA-viruses. Particularly, many defense-related and hormone-responsive genes (e.g. ethylene responsive transcription factor 1, ERF1) were differentially regulated in these plants. Also the expression of several stress-related genes, and genes related to cell wall modifications, protein processing, transcriptional regulation and photosynthesis were strongly altered. Moreover, genes regulating circadian cycle and flowering time were significantly altered, which may have induced a late flowering phenotype in HC-Pro expressing plants. The results also suggest that photosynthetic oxygen evolution, sugar metabolism and energy levels were significantly changed in these transgenic plants. Transcript levels of S-adenosyl-L-methionine (SAM) were also decreased in

  3. Plasma devices for hydrocarbon reformation

    KAUST Repository

    Cha, Min Suk

    2017-02-16

    Plasma devices for hydrocarbon reformation are provided. Methods of using the devices for hydrocarbon reformation are also provided. The devices can include a liquid container to receive a hydrocarbon source, and a plasma torch configured to be submerged in the liquid. The plasma plume from the plasma torch can cause reformation of the hydrocarbon. The device can use a variety of plasma torches that can be arranged in a variety of positions in the liquid container. The devices can be used for the reformation of gaseous hydrocarbons and/or liquid hydrocarbons. The reformation can produce methane, lower hydrocarbons, higher hydrocarbons, hydrogen gas, water, carbon dioxide, carbon monoxide, or a combination thereof.

  4. Plant hydrocarbon recovery process

    Energy Technology Data Exchange (ETDEWEB)

    Dzadzic, P.M.; Price, M.C.; Shih, C.J.; Weil, T.A.

    1982-01-26

    A process for production and recovery of hydrocarbons from hydrocarbon-containing whole plants in a form suitable for use as chemical feedstocks or as hydrocarbon energy sources which process comprises: (A) pulverizing by grinding or chopping hydrocarbon-containing whole plants selected from the group consisting of euphorbiaceae, apocynaceae, asclepiadaceae, compositae, cactaceae and pinaceae families to a suitable particle size, (B) drying and preheating said particles in a reducing atmosphere under positive pressure (C) passing said particles through a thermal conversion zone containing a reducing atmosphere and with a residence time of 1 second to about 30 minutes at a temperature within the range of from about 200* C. To about 1000* C., (D) separately recovering the condensable vapors as liquids and the noncondensable gases in a condition suitable for use as chemical feedstocks or as hydrocarbon fuels.

  5. Effect of hydrocarbons and crude oil contamination on the sensitivity of French bean to alfalfa mosaic virus.

    Science.gov (United States)

    Jurík, M; Gallo, J; Subr, Z

    1995-12-01

    Determination of local necrotic lesions on primary leaves infected by alfalfa mosaic virus (AMV) revealed that hydrocarbons (HC) contamination of the substrate used for cultivation of French bean (Phaseolus vulgaris L., cv. Black Turtle Soup) caused a reduction of bean leaf area and an increase of plant sensitivity to AMV infection. On the other hand, superficial contamination of the leaves by crude oil caused an inhibition of lesion formation. Changes of SDS-polyacrylamide gel electrophoresis (SDS-PAGE) patterns of extractable bean leaf proteins related to the cultivation substrate contamination by HC were also detected.

  6. DEG系统和HC VWS系统的差异性分析%On difference analysis of DEG system and HC VWS system

    Institute of Scientific and Technical Information of China (English)

    刘倩平; 汪鹏; 刘占盛; 张凤阁

    2016-01-01

    The paper introduces the components for"M310 Second Generation Plus"DEG system and"AP1000 reactor type"HC VWS system, indicates their differences from the allocation of water chilling unit,return water temperature differences of chilled water,end loading adjustment, and services of water chilling system,and sums up the design experience for the advanced design ideas referring to the two aspects,so as to ac-complish the design for the Hualong No. 1(ACP1000)nuclear island water chilling system.%介绍了"M310二代加"DEG系统和"AP1000堆型"HC VWS系统的组成要素,从冷水机组配置、冷冻水供回水温差、末端负荷调节方式、冷冻水系统服务范围等方面,论述了两者的差异性,在总结及借鉴二者的先进设计理念和设计经验的基础上,完成了华龙一号( ACP1000)的核岛冷冻水系统设计工作.

  7. Exhaust emissions reduction from diesel engine using combined Annona-Eucalyptus oil blends and antioxidant additive

    Science.gov (United States)

    Senthil, R.; Silambarasan, R.; Pranesh, G.

    2017-03-01

    The limited resources, rising petroleum prices and depletion of fossil fuel have now become a matter of great concern. Hence, there is an urgent need for researchers to find some alternate fuels which are capable of substituting partly or wholly the higher demanded conventional diesel fuel. Lot of research work has been conducted on diesel engine using biodiesel and its blends with diesel as an alternate fuel. Very few works have been done with combination of biodiesel-Eucalypts oil without neat diesel and this leads to lots of scope in this area. The aim of the present study is to analyze the performance and emission characteristics of a single cylinder, direct injection, compression ignition engine using eucalyptus oil-biodiesel as fuel. The presence of eucalyptus oil in the blend reduces the viscosity and improves the volatility of the blends. The methyl ester of Annona oil is blended with eucalypts oil in 10, 20, 30, 40 and 50 %. The performance and emission characteristics are evaluated by operating the engine at different loads. The performance characteristics such as brake thermal efficiency, brake specific fuel consumption and exhaust gas temperature are evaluated. The emission constituents measured are Carbon monoxide (CO), unburned hydrocarbons (HC), Oxides of nitrogen (NOx) and Smoke. It is found that A50-Eu50 (50 Annona + 50 % Eucalyptus oil) blend showed better performance and reduction in exhaust emissions. But, it showed a very marginal increase in NOx emission when compared to that of diesel. Therefore, in order to reduce the NOx emission, antioxidant additive (A-tocopherol acetate) is mixed with Annona-Eucalyptus oil blends in various proportions by which NOx emission is reduced. Hence, A50-Eu50 blend can be used as an alternate fuel for diesel engine without any modifications.

  8. Exhaust emissions reduction from diesel engine using combined Annona-Eucalyptus oil blends and antioxidant additive

    Science.gov (United States)

    Senthil, R.; Silambarasan, R.; Pranesh, G.

    2016-07-01

    The limited resources, rising petroleum prices and depletion of fossil fuel have now become a matter of great concern. Hence, there is an urgent need for researchers to find some alternate fuels which are capable of substituting partly or wholly the higher demanded conventional diesel fuel. Lot of research work has been conducted on diesel engine using biodiesel and its blends with diesel as an alternate fuel. Very few works have been done with combination of biodiesel-Eucalypts oil without neat diesel and this leads to lots of scope in this area. The aim of the present study is to analyze the performance and emission characteristics of a single cylinder, direct injection, compression ignition engine using eucalyptus oil-biodiesel as fuel. The presence of eucalyptus oil in the blend reduces the viscosity and improves the volatility of the blends. The methyl ester of Annona oil is blended with eucalypts oil in 10, 20, 30, 40 and 50 %. The performance and emission characteristics are evaluated by operating the engine at different loads. The performance characteristics such as brake thermal efficiency, brake specific fuel consumption and exhaust gas temperature are evaluated. The emission constituents measured are Carbon monoxide (CO), unburned hydrocarbons (HC), Oxides of nitrogen (NOx) and Smoke. It is found that A50-Eu50 (50 Annona + 50 % Eucalyptus oil) blend showed better performance and reduction in exhaust emissions. But, it showed a very marginal increase in NOx emission when compared to that of diesel. Therefore, in order to reduce the NOx emission, antioxidant additive (A-tocopherol acetate) is mixed with Annona-Eucalyptus oil blends in various proportions by which NOx emission is reduced. Hence, A50-Eu50 blend can be used as an alternate fuel for diesel engine without any modifications.

  9. Assessment of Hydrocarbon Generation Potential of Permian Gondwana Coals, Bangladesh

    Directory of Open Access Journals (Sweden)

    H. M. Zakir Hossain

    2013-06-01

    Full Text Available This paper represents the geochemical characteristics of Gondwana coals from the Barapukuria coal mine, Bangladesh in order to investigate the potential for hydrocarbon generation. A total number of twenty three coal samples were analyzed Rock-Eval pyrolysis, CHNS elemental analyses, maceral analysis and vitrinite reflectance. The samples were collected from drill hole GDH-40 of the Barapukuria coal mine encountered within Gondwana succession of Permian age. The TOC contents of the coal samples range between ~50 and 76 wt.% and the organic matter consists predominantly of type III and type IV kerogen with respect to hydrocarbon generation. The GP, HI, PI and Tmax values range between 7 and 35 mg HC/g rock, 20 and 62 mg HC/g TOC, 0.02 and 0.04, and 430 and 437oC, respectively. The organic matter is mainly gas prone and thermally immature to early mature level. The potential coal bed methane (CBM generation of the Barapukuria basin is estimated to be 11 Gm3. Thus, underground coal gasification (UCG is helpful for better development of subsurface coals at the Barapukuria basin, Bangladesh.

  10. Three millimeter molecular line observations in Sagittarius B2. 1: Full synthesis mapping study of HNO, CCS, and HC(13)CCN

    Science.gov (United States)

    Kuan, Yi-Jehng; Snyder, Lewis E.

    1994-01-01

    We present the first full synthesis maps of the small molecules HNO, CCS, and HC(13)CCN in Sgr B2. We have observed the 3.8 mm continuum, the HNO J(sub K(sub -1)K(sub 1)) = 1(sub O1)-0(sub OO), the CCS J(sub N) = 7(sub 6)-6(sub 5), and the HC(13)CCN J = 9-8 transitions in the core of the Sgr B2 molecular cloud, using the Berkeley Illinois Maryland Association (BIMA) millimeter array and the NRAO 12 m telescope. We have found that HNO exists in five major gas clumps in the Sgr B2 region, which we have labeled HNO(N), HNO(NW), HNO(E), HNO(M), and HNO(S). Of particular interest is HNO(M), a major molecular gas concentration approximately 15 sec west of Sgr B2(M) in a region of young star formation. HNO is found to be closely associated with the ionized gas and might be depleted around bright H II complexes. In general, the peak intensity of the HNO emission is found to be offset from the peak of the continuum emission. We found evidence for some chemical differentiation among the three species, HNO, CCS, and HC(13)CCN, but the abundance ratios are in fair agreement with theoretical models. Two unidentified lines, U81420 and U81518, were observed, and a previously unknown compact dust source was detected. Our HNO data indicate the presence of a rotating approximately (2.2-4.4) x 10(exp 3)solar mass gas envelope surrounding Sgr B2(N), a possible bipolar gas outflow in HNO(M), and possibly a large (approximately 4.2 x 10(exp 4)solar mass) extended rotating disk associated with HNO(S). In addition, the CCS and HC(13)CCN data approximately outline the extended component of Sgr B2 and clearly show that the southern continuum source Sgr B2(S) is actually a major molecular source as well. Consequently, the kinematics of the Sgr B2 molecular cloud is quite complex, but in moving from the northwest to south, the LSR velocity generally changes from 79 to 46 km/s.

  11. Transgenic plants expressing HC-Pro show enhanced virus sensitivity while silencing of the transgene results in resistance

    NARCIS (Netherlands)

    Mlotshwa, S.; Verver, J.; Sithole-Niang, I.; Prins, M.; Kammen, van A.; Wellink, J.

    2002-01-01

    Nicotiana benthamiana plants were engineered to express sequences of the helper component-proteinase (HC-Pro) of Cowpea aphid-borne mosaic potyvirus (CABMV). The sensitivity of the transgenic plants to infection with parental and heterologous viruses was studied. The lines expressing HC-Pro showed

  12. Relationship between interRAI HC and the ICF: opportunity for operationalizing the ICF

    Directory of Open Access Journals (Sweden)

    Ljunggren Gunnar

    2009-03-01

    Full Text Available Abstract Background The International Classification of Functioning, Disability and Health (ICF is embraced as a framework to conceptualize human functioning and disability. Health professionals choose measures to represent the domains of the framework. The ICF coding classification is an administrative system but multiple studies have linked diverse clinical assessments to ICF codes. InterRAI-HC (home care is an assessment designed to assist planning of care for patients receiving home care. Examining the relationship between the ICF and the interRAI HC is of particular interest because the interRAI assessments are widely used in clinical practice and research, are computerized, and uploaded to databases that serve multiple purposes including public reporting of quality in Canada and internationally. The objective of this study was to examine the relationship between the interRAI HC (home care assessment and the ICF. Specifically, the goal was to determine the proportion of interRAI HC items that can be linked to each of the major domains of the ICF (Body Function, Body Structure, Activities and Participation, and the Environmental Factors, the chapters and the specific ICF codes. Methods Three coders who were familiar with both the home care assessment and the ICF independently assigned ICF codes to inter-RAI HC items. Subsequently, a series of teleconference meetings were held to reach consensus on the primary code and much later consensus was used to finalize codes for additional items added to the interRAI HC. Results Following exclusion of administrative and diagnostic sections, 175 interRAI items were examined for potential assignment of codes. Of these 52 were assigned codes related to body function, 43 to activities and participation, 34 to environment, 1 to body structure, 17 to not coded, and 26 to not defined. Considering all 3-digit ICF codes, interRAI items addressed 43.2% of Body Function and 50.6% of Activities and Participation

  13. Regulated and unregulated emissions from a diesel engine fueled with diesel fuel blended with diethyl adipate

    Science.gov (United States)

    Zhu, Ruijun; Cheung, C. S.; Huang, Zuohua; Wang, Xibin

    2011-04-01

    Experiments were carried out on a four-cylinder direct-injection diesel engine operating on Euro V diesel fuel blended with diethyl adipate (DEA). The blended fuels contain 8.1%, 16.4%, 25% and 33.8% by volume fraction of DEA, corresponding to 3%, 6%, 9% and 12% by mass of oxygen in the blends. The engine performance and exhaust gas emissions of the different fuels were investigated at five engine loads at a steady speed of 1800 rev/min. The results indicated an increase of brake specific fuel consumption and brake thermal efficiency when the engine was fueled with the blended fuels. In comparison with diesel fuel, the blended fuels resulted in an increase in hydrocarbon (HC) and carbon monoxide (CO), but a decrease in particulate mass concentrations. The nitrogen oxides (NO x) emission experienced a slight variation among the test fuels. In regard to the unregulated gaseous emissions, formaldehyde and acetaldehyde increased, while 1,3-butadiene, ethene, ethyne, propylene and BTX (benzene, toluene and xylene) in general decreased. A diesel oxidation catalyst (DOC) was found to reduce significantly most of the investigated unregulated pollutants when the exhaust gas temperature was sufficiently high.

  14. Bioethanol/gasoline blends for fuelling conventional and hybrid scooter. Regulated and unregulated exhaust emissions

    Science.gov (United States)

    Costagliola, Maria Antonietta; Prati, Maria Vittoria; Murena, Fabio

    2016-05-01

    The aim of this experimental activity was to evaluate the influence of ethanol fuel on the pollutant emissions measured at the exhaust of a conventional and a hybrid scooter. Both scooters are 4-stroke, 125 cm3 of engine capacity and Euro 3 compliant. They were tested on chassis dynamometer for measuring gaseous emissions of CO, HC, NOx, CO2 and some toxic micro organic pollutants, such as benzene, 1,3-butadiene, formaldehyde and acetaldehyde. The fuel consumption was estimated throughout a carbon balance on the exhaust species. Moreover, total particles number with diameter between 20 nm up to 1 μm was measured. Worldwide and European test cycles were carried out with both scooters fuelled with gasoline and ethanol/gasoline blends (10/90, 20/80 and 30/70% vol). According to the experimental results relative to both scooter technologies, the addiction of ethanol in gasoline reduces CO and particles number emissions. The combustion of conventional scooter becomes unstable when a percentage of 30%v of bioethanol is fed; as consequence a strong increasing of hydrocarbon is monitored, including carcinogenic species. The negative effects of ethanol fuel are related to the increasing of fuel consumption due to the less carbon content for volume unit and to the increasing of formaldehyde and acetaldehyde due to the higher oxygen availability. Almost 70% of Ozone Formation Potential is covered by alkenes and aromatics.

  15. A study on emission performance of a diesel engine fueled with five typical methyl ester biodiesels

    Science.gov (United States)

    Wu, Fujia; Wang, Jianxin; Chen, Wenmiao; Shuai, Shijin

    As an alternative and renewable fuel, biodiesel can effectively reduce diesel engine emissions, especially particulate matter and dry soot. However, the biodiesel effects on emissions may vary as the source fuel changes. In this paper, the performance of five methyl esters with different sources was studied: cottonseed methyl ester (CME), soybean methyl ester (SME), rapeseed methyl ester (RME), palm oil methyl ester (PME) and waste cooking oil methyl ester (WME). Total particulate matter (PM), dry soot (DS), non-soot fraction (NSF), nitrogen oxide (NO x), unburned hydrocarbon (HC), and carbon monoxide (CO) were investigated on a Cummins ISBe6 Euro III diesel engine and compared with a baseline diesel fuel. Results show that using different methyl esters results in large PM reductions ranging from 53% to 69%, which include the DS reduction ranging from 79% to 83%. Both oxygen content and viscosity could influence the DS emission. Higher oxygen content leads to less DS at high load while lower viscosity results in less DS at low load. NSF decreases consistently as cetane number increases except for PME. The cetane number could be responsible for the large NSF difference between different methyl esters.

  16. Determining gaseous emission factors and driver's particle exposures during traffic congestion by vehicle-following measurement techniques.

    Science.gov (United States)

    Tang, U Wa; Wang, Zhishi

    2006-11-01

    Vehicle gaseous emissions (NO, CO, CO2, and hydrocarbon [HC]) and driver's particle exposures (particulate matter traffic congestion in Macao, Special Administrative Region, People's Republic of China, an urban area having one of the highest population densities in the world. The measurements were taken with high time resolution so that fluctuations in the emissions can be seen readily during vehicle acceleration, cruising, deceleration, and idling. The tests were conducted in close proximity to the vehicles, with the inlet of a five-gas analyzer mounted on the front bumper of the mobile laboratory, and the distance between the vehicles was usually within several meters. To measure the driver's particle exposures, the inlets of the particle analyzers were mounted at the height of the driver's breathing position in the mobile laboratory, with the driver's window open. A total of 178 and 113 vehicles were followed individually to determine the gaseous emission factor and the driver's particle exposures, respectively, for motorcycle, passenger car, taxi, truck, and bus. The gaseous emission factors were used to model the roadside air quality, and good correlations between the modeled and monitored CO, NO2, and nitrogen oxide (NO(x)) verified the reliability of the experiments. Compared with petrol passenger cars and petrol trucks, diesel taxies and diesel trucks emitted less CO but more NO(x). The impact of urban canyons is shown to cause a significant increase in the PM1 peak. The background concentrations contributed a significant amount of the driver's particle exposures.

  17. Biological control of wheat root diseases by the CLP-producing strain Pseudomonas fluorescens HC1-07.

    Science.gov (United States)

    Yang, Ming-Ming; Wen, Shan-Shan; Mavrodi, Dmitri V; Mavrodi, Olga V; von Wettstein, Diter; Thomashow, Linda S; Guo, Jian-Hua; Weller, David M

    2014-03-01

    Pseudomonas fluorescens HC1-07, previously isolated from the phyllosphere of wheat grown in Hebei province, China, suppresses the soilborne disease of wheat take-all, caused by Gaeumannomyces graminis var. tritici. We report here that strain HC1-07 also suppresses Rhizoctonia root rot of wheat caused by Rhizoctonia solani AG-8. Strain HC1-07 produced a cyclic lipopeptide (CLP) with a molecular weight of 1,126.42 based on analysis by electrospray ionization mass spectrometry. Extracted CLP inhibited the growth of G. graminis var. tritici and R. solani in vitro. To determine the role of this CLP in biological control, plasposon mutagenesis was used to generate two nonproducing mutants, HC1-07viscB and HC1-07prtR2. Analysis of regions flanking plasposon insertions in HC1-07prtR2 and HC1-07viscB revealed that the inactivated genes were similar to prtR and viscB, respectively, of the well-described biocontrol strain P. fluorescens SBW25 that produces the CLP viscosin. Both genes in HC1-07 were required for the production of the viscosin-like CLP. The two mutants were less inhibitory to G. graminis var. tritici and R. solani in vitro and reduced in ability to suppress take-all. HC1-07viscB but not HC-07prtR2 was reduced in ability to suppress Rhizoctonia root rot. In addition to CLP production, prtR also played a role in protease production.

  18. Interaction between the Chlamydia trachomatis histone H1-like protein (Hc1) and DNA

    DEFF Research Database (Denmark)

    Christiansen, Gunna; Pedersen, LB; Koehler, JF;

    1993-01-01

    The gene encoding the Chlamydia trachomatis histone H1-like protein (Hc1) from serovar L2 was cloned into Escherichia coli by use of expression vector pET11d. In this vector, transcription of the gene is under the control of a bacteriophage T7 promoter, and T7 RNA polymerase is inducible in the h......The gene encoding the Chlamydia trachomatis histone H1-like protein (Hc1) from serovar L2 was cloned into Escherichia coli by use of expression vector pET11d. In this vector, transcription of the gene is under the control of a bacteriophage T7 promoter, and T7 RNA polymerase is inducible...

  19. Med H.C. Andersen i Portugal år 1866

    DEFF Research Database (Denmark)

    Skousbøll, Karin

    2004-01-01

    Bogen er et genoptryk af en udgivelse fra 1975 i anledning af 150 året for H.C. Andersens død. Udgangspunktet var H.C. Andersens beskrivelse af rejse til Portugal i 1866, hvor han bl.a. besøgte familien O'Neill på deres landsted (Quinta) nær ved Lissabon. Vi er med den rejsende digter fra hans...... ankomst med diligence fra Spanien ind over fastlandet til Lissabon, men også rundt i byen, i omegnen og til havnebyen Setubal. Det indsamlede billedstof som underbygger teksten er dels historisk stof indhentet fra Det kg. Bibliotek o.a. kilder og dels fremskaffet fra Portugals arkiver og de respektive...

  20. Observation of h_c(^1P_1) State of Charmonium

    CERN Document Server

    Rosner, J L; Lee, J; Miller, D H; Pavlunin, V; Rangarajan, R; Sanghi, B; Shibata, E I; Shipsey, I P J; Cronin-Hennessy, D; Park, C S; Park, W; Thayer, J B; Thorndike, E H; Coan, T E; Gao, Y S; Liu, F; Stroynowski, R; Artuso, M; Boulahouache, C; Blusk, S; Dambasuren, E; Dorjkhaidav, O; Mountain, R; Muramatsu, H; Nandakumar, R; Skwarnicki, T; Stone, S; Wang, J C; Csorna, S E; Danko, I; Bonvicini, G; Cinabro, D; Dubrovin, M; McGee, S; Bornheim, A; Lipeles, E; Pappas, S P; Shapiro, A; Sun, W M; Weinstein, A J; Briere, R A; Chen, G P; Ferguson, T; Tatishvili, G T; Vogel, H; Watkins, M E; Adam, N E; Alexander, J P; Berkelman, K; Boisvert, V; Cassel, D G; Duboscq, J E; Ecklund, K M; Ehrlich, R; Galik, R S; Gibbons, L; Gittelman, B; Gray, S W; Hartill, D L; Heltsley, B K; Hsu, L; Jones, C D; Kandaswamy, J; Kreinick, D L; Magerkurth, A; Mahlke-Krüger, H; Meyer, T O; Mistry, N B; Patterson, J R; Peterson, D; Pivarski, J; Richichi, S J; Riley, D; Sadoff, A J; Schwarthoff, H; Shepherd, M R; Thayer, J G; Urner, D; Wilksen, T; Warburton, A; Weinberger, M; Athar, S B; Avery, P; Breva-Newell, L; Potlia, V; Stöck, H; Yelton, J; Benslama, K; Cawlfield, C; Eisenstein, B I; Gollin, G D; Karliner, I; Lowrey, N; Plager, C; Sedlack, C; Selen, M; Thaler, J J; Williams, J; Edwards, K W; Besson, D; Anderson, S; Frolov, V V; Gong, D T; Kubota, Y; Li, S Z; Poling, R A; Smith, A; Stepaniak, C J; Urheim, J; Metreveli, Z V; Seth, K K; Tomaradze, A G; Zweber, P; Ahmed, S; Alam, M S; Ernst, J; Jian, L; Saleem, M; Wappler, F; Arms, K; Eckhart, E; Gan, K K; Gwon, C; Honscheid, K; Kagan, H; Kass, R; Pedlar, T K; Von Törne, E; Severini, H; Skubic, P L; Dytman, S A; Müller, J A; Nam, S; Savinov, V; Hinson, J W

    2005-01-01

    The h_c(1P1) state of charmonium has been observed in the reaction \\psi(2S) -> \\pi0 h_c -> (\\gamma\\gamma)(\\gamma\\eta_c) using 3.08 million \\psi(2S) decays recorded in the CLEO detector. Data have been analyzed both for the inclusive reaction, where the decay products of the \\eta_c are not identified, and for exclusive reactions, in which \\eta_c decays are reconstructed in seven hadronic decay channels. We find M(h_c)=3524.4 +/- 0.6 +/- 0.4 MeV which corresponds to a hyperfine splitting \\Delta M_{hf}(1P) \\equiv -M(1P1)=+1.0+/-0.6+/-0.4 MeV, and B(\\psi(2S)->\\pi0 h_c)xB(h_c->\\gamma\\eta_c)=(4. +/-0.8+/-0.7)x10^{-4}.

  1. Semileptonic Decays of Bc Meson to a P-Wave Charmonium State Xc or hc

    Institute of Scientific and Technical Information of China (English)

    CHANG Chao-Hsi; CHEN Yu-Qi; WANG Guo-Li; ZONG Hong-Shi

    2001-01-01

    The semileptonic decays of meson Bc to a P-wave charmonium state χc(3PJ) or hc(1P1) are computed. The results show that the decays are sizable so they are accessible in Tevatron and LHC, especially, with the detectors LHCB and BTeV in the foreseeable future, and of them, the one to the 1P1 charmonium state potentially offers us a novel window to see the unconfirmed hc particle. In addition, it is pointed out that since the two charmonium radiative decays χc(3P1,2) → J/ψ + γ have sizable branching ratios, the cascade decays of the concerned decays and the charmonium radiative decays may affect the result of observing Bc meson through the semileptonic decays Bc→J/ψ+l + vi substantially.

  2. Thraustochytrid protists degrade hydrocarbons

    Digital Repository Service at National Institute of Oceanography (India)

    Raikar, M.T.; Raghukumar, S.; Vani, V.; David, J.J.; Chandramohan, D.

    Although thraustochytrid protists are known to be of widespread occurrence in the sea, their hydrocarbon-degrading abilities have never been investigated. We isolated thraustochytrids from coastal waters and sediments of Goa coast by enriching MPN...

  3. Combination of biodiesel-ethanol-diesel fuel blend and SCR catalyst assembly to reduce emissions from a heavy-duty diesel engine.

    Science.gov (United States)

    Shi, Xiaoyan; Yu, Yunbo; He, Hong; Shuai, Shijin; Dong, Hongyi; Li, Rulong

    2008-01-01

    In this study, the efforts to reduce NOx and particulate matter (PM) emissions from a diesel engine using both ethanol-selective catalytic reduction (SCR) of NOx over an Ag/Al2O3 catalyst and a biodiesel-ethanol-diesel fuel blend (BE-diesel) on an engine bench test are discussed. Compared with diesel fuel, use of BE-diesel increased PM emissions by 14% due to the increase in the soluble organic fraction (SOF) of PM, but it greatly reduced the Bosch smoke number by 60%-80% according to the results from 13-mode test of European Stationary Cycle (ESC) test. The SCR catalyst was effective in NOx reduction by ethanol, and the NOx conversion was approximately 73%. Total hydrocarbons (THC) and CO emissions increased significantly during the SCR of NOx process. Two diesel oxidation catalyst (DOC) assemblies were used after Ag/Al2O3 converter to remove CO and HC. Different oxidation catalyst showed opposite effect on PM emission. The PM composition analysis revealed that the net effect of oxidation catalyst on total PM was an integrative effect on SOF reduction and sulfate formation of PM. The engine bench test results indicated that the combination of BE-diesel and a SCR catalyst assembly could provide benefits for NOx and PM emissions control even without using diesel particle filters (DPFs).

  4. Enhancement of H_c2 in MgB2 Wires through Carbon Substitution

    Science.gov (United States)

    Finnemore, D. K.; Wilke, R. H. T.; Straszheim, W. E.; Sailsbury, H.; Bud'Ko, S. L.; Canfield, P. C.; Suplinskas, R. J.; Hannahs, S. T.

    2004-03-01

    A series of carbon substituted Mg(B_1-xC_x)2 wires were fabricated in a two step process by co-depositing carbon and boron on a tungsten filament using a CVD reaction. These starting fibers had nominal carbon concentrations of 0.5,1, and 2 percent as determined from the C to B ratio in the CVD gas stream. The conversion to Mg(B_1-xC_x)2 was carried out by heating the C-doped B fiber in a Mg vapor.[1] The temperature dependence of H_c2 was measured resistively in fields up to 33 T. Carbon doping results in relatively minor decrease in Tc from 39.2 to 36.2 K, while simultaneously increasing H_c2(0) from 16 to 33 T. We have shown carbon is an effective dopant for increasing H_c2 and our data suggest even higher critical fields can be achieved with nominal concentrations around 4-5 [1] P.C. Canfield, D. K. Finnemore, S.L. Bud'ko, J.E. Ostenson, G. Lapertot, C.E. Cunnigham, and C. Petrovic, Phys. Rev. Lett. 86, 2423 (2001).

  5. Precision Measurement of the Mass of the h_c(1P1) State of Charmonium

    CERN Document Server

    Dobbs, S; Seth, K K; Tomaradze, A G; Libby, J; Powell, A; Wilkinson, G; Ecklund, K M; Love, W; Savinov, V; López, A; Méndez, H; Ramírez, J; Ge, J Y; Miller, D H; Shipsey, I P J; Xin, B; Adams, G S; Anderson, M; Cummings, J P; Danko, I; Hu, D; Moziak, B; Napolitano, J; He, Q; Insler, J; Muramatsu, H; Park, C S; Thorndike, E H; Yang, F; Artuso, M; Blusk, S; Khalil, S; Li, J; Mountain, R; Nisar, S; Randrianarivony, K; Sultana, N; Skwarnicki, T; Stone, S; Wang, J C; Zhang, L M; Bonvicini, G; Cinabro, D; Dubrovin, M; Lincoln, A; Naik, P; Rademacker, J; Asner, D M; Edwards, K W; Reed, J; Briere, R A; Ferguson, T; Tatishvili, G; Vogel, H; Watkins, M E; Rosner, J L; Alexander, J P; Cassel, D G; Duboscq, J E; Ehrlich, R; Fields, L; Galik, R S; Gibbons, L; Gray, R; Gray, S W; Hartill, D L; Heltsley, B K; Hertz, D; Hunt, J M; Kandaswamy, J; Kreinick, D L; Kuznetsov, V E; Ledoux, J; Mahlke-Krüger, H; Mohapatra, D; Onyisi, P U E; Patterson, J R; Peterson, D; Riley, D; Ryd, A; Sadoff, A J; Shi, X; Stroiney, S; Sun, W M; Wilksen, T; Athar, S B; Patel, R; Yelton, J; Rubin, P; Eisenstein, B I; Karliner, I; Mehrabyan, S; Lowrey, N; Selen, M; White, E J; Wiss, J; Mitchell, R E; Shepherd, M R; Besson, D; Pedlar, T K; Cronin-Hennessy, D; Gao, K Y; Hietala, J; Kubota, Y; Klein, T; Lang, B W; Poling, R; Scott, A W; Zweber, P

    2008-01-01

    A precision measurement of the mass of the h_c(1P1) state of charmonium has been made using a sample of 24.5 million psi(2S) events produced in e+e- annihilation at CESR. The reaction used was psi(2S) -> pi0 h_c, pi0 -> gamma gamma, h_c -> gamma eta_c, and the reaction products were detected in the CLEO-c detector. Data have been analyzed both for the inclusive reaction and for the exclusive reactions in which eta_c decays are reconstructed in fifteen hadronic decay channels. Consistent results are obtained in the two analyses. The averaged results of the present measurements are M(h_c)=3525.28+-0.19 (stat)+-0.12(syst) MeV, and B(psi(2S) -> pi0 h_c)xB(h_c -> gamma eta_c)= (4.19+-0.32+-0.45)x10^-4. Using the 3PJ centroid mass, Delta M_hf(1P)= - M(h_c) = +0.02+-0.19+-0.13 MeV.

  6. Millimetre-wave spectroscopy of HC{sub 4}Cl in ground and excited vibrational states

    Energy Technology Data Exchange (ETDEWEB)

    Bizzocchi, Luca [Dipartimento di Chimica ' G. Ciamician' , Universita di Bologna, via F. Selmi 2, 40126 Bologna (Italy)], E-mail: luca.bizzocchi@unibo.it; Degli Esposti, Claudio [Dipartimento di Chimica ' G. Ciamician' , Universita di Bologna, via F. Selmi 2, 40126 Bologna (Italy)], E-mail: claudio.degliesposti@unibo.it

    2008-05-04

    The semi-stable HC{sub 4}Cl molecule has been detected in the pyrolysis products of propyne and carbon tetrachloride mixtures. The rotational spectrum of the most abundant isotopologue HC{sub 4}{sup 35}Cl has been investigated in the millimetre- and sub-millimetre-wave regions for the ground and 12 vibrationally excited states which approximately lie below 630 cm{sup -1}, namely ({nu}{sub 5}{nu}{sub 6}{nu}{sub 7}{nu}{sub 8}{nu}{sub 9})=(10000), (01000), (00100), (00010), (00001), (00020), (00002), (00003), (00004), (00101), (00011) and (00012). Transitions up to J=151 <- 150 were measured for the ground state, allowing for a precise evaluation of the quartic and sextic centrifugal distortion constants D and H. The l-type resonances between the different sublevels of the bending states and the anharmonic resonance which couples the states {nu}{sub 5}=1, {nu}{sub 8}=2 and {nu}{sub 9}=4 have been taken into account in the analysis of the spectra, which yielded precise determinations of the x{sub L(99)}, x{sub L(88)}, x{sub L(89)} and x{sub L(79)} anharmonicity constants and of the {phi}{sub 588} normal coordinate cubic force constant. Extensive measurements have also been performed for the HC{sub 4}{sup 37}Cl isotopologue.

  7. Characterization of Bacillus subtilis HC8, a novel plant-beneficial endophytic strain from giant hogweed.

    Science.gov (United States)

    Malfanova, Natalia; Kamilova, Faina; Validov, Shamil; Shcherbakov, Andrey; Chebotar, Vladimir; Tikhonovich, Igor; Lugtenberg, Ben

    2011-07-01

    Thirty endophytic bacteria were isolated from various plant species growing near Saint-Petersburg, Russia. Based on a screening for various traits, including plant-beneficial properties and DNA fragment patterns, potential siblings were removed. The remaining isolates were taxonomically identified using 16S rDNA sequences and potential human and plant pathogens were removed. The remaining strains were tested for their ability to promote radish root growth and to protect tomato plants against tomato foot and root rot. One strain, Bacillus subtilis HC8, isolated from the giant hogweed Heracleum sosnowskyi Manden, significantly promoted plant growth and protected tomato against tomato foot and root rot. Metabolites possibly responsible for these plant-beneficial properties were identified as the hormone gibberellin and (lipo)peptide antibiotics respectively. The antibiotic properties of strain HC8 are similar to those of the commercially available plant-beneficial strain Bacillus amyloliquefaciens FZB42. However, thin layer chromatography profiles of the two strains differ. It is speculated that endophytes such as B. subtilis HC8 contribute to the fast growth of giant hogweed. © 2011 Leiden University, Institute of Biology. Journal compilation © 2011 Society for Applied Microbiology and Blackwell Publishing Ltd.

  8. Characterization of Bacillus subtilis HC8, a novel plant‐beneficial endophytic strain from giant hogweed

    Science.gov (United States)

    Malfanova, Natalia; Kamilova, Faina; Validov, Shamil; Shcherbakov, Andrey; Chebotar, Vladimir; Tikhonovich, Igor; Lugtenberg, Ben

    2011-01-01

    Summary Thirty endophytic bacteria were isolated from various plant species growing near Saint‐Petersburg, Russia. Based on a screening for various traits, including plant‐beneficial properties and DNA fragment patterns, potential siblings were removed. The remaining isolates were taxonomically identified using 16S rDNA sequences and potential human and plant pathogens were removed. The remaining strains were tested for their ability to promote radish root growth and to protect tomato plants against tomato foot and root rot. One strain, Bacillus subtilis HC8, isolated from the giant hogweed Heracleum sosnowskyi Manden, significantly promoted plant growth and protected tomato against tomato foot and root rot. Metabolites possibly responsible for these plant‐beneficial properties were identified as the hormone gibberellin and (lipo)peptide antibiotics respectively. The antibiotic properties of strain HC8 are similar to those of the commercially available plant‐beneficial strain Bacillus amyloliquefaciens FZB42. However, thin layer chromatography profiles of the two strains differ. It is speculated that endophytes such as B. subtilis HC8 contribute to the fast growth of giant hogweed. PMID:21366893

  9. Recovery of Aliphatic Hydrocarbons from Oil Field Sludge using Bacillus sp

    Directory of Open Access Journals (Sweden)

    Rizwan Ahmed Bhutto

    2015-04-01

    Full Text Available Bioremediation of aliphatic HC (Hydrocarbons in the oily sludge of Kunnar oil and gas field, Pakistan was attempted by means of previously isolated and developed Bacillus sp. Both autoclaved and non-autoclaved sludge samples were analyzed for a reaction time of 30 days with pH 7 and temperature of 380C in 50 ml MSM growth media for the sludge concentration of 5, 10 and 50% with 2, 4 and 6ml of Bacillus sp. relatively, in air atmosphere. Stabilization of the samples by microbial activity resulted in the decrease in TPH (Total Petroleum Hydrocarbon concentration by 60, 69 and 87% in autoclaved samples in contrast to the decrease of 70, 84 and 94% observed in non-autoclaved samples, relatively. Hydrocarbon degradation in oily sludge was investigated via GC which transpired that 97 and 99% concentration of aliphatic hydrocarbons in autoclaved and non-autoclaved samples was removed at 5% of TPH concentration, relatively. However, with 10% TPH concentration aliphatic hydrocarbons reduction was 68% in autoclaved samples to that of 87% in non-autoclaved samples. Further increase in the hydrocarbons concentration by 50% yielded in the removal of aliphatic hydrocarbons by 65% in autoclaved samples as compared to 98% decrease in non-autoclaved samples.

  10. Green Methodologies to Test Hydrocarbon Reservoirs

    Directory of Open Access Journals (Sweden)

    Francesca Verga

    2010-01-01

    Full Text Available Problem statement: The definition and the economic viability of the best development strategy of a hydrocarbon reservoir mainly depend on the quantity and type of fluids and on the well productivity. Well testing, consisting in producing hydrocarbon to the surface while measuring the pressure variations induced in the reservoir, has been used for decades to determine the fluid nature and well potential. In exploration and appraisal scenarios the hydrocarbons produced during a test are flared, contributing to the emissions of greenhouse gases. Approach: Due to more stringent environmental regulations and a general need for reduced operating expenses, the current industry drivers in today’s formation evaluation methodologies demand short, safe, cost-effective and environmentally friendly test procedures, especially when conventional tests are prohibitively expensive, logistically not feasible or no surface emissions are allowed. Different methods have been proposed or resuscitated in the last years, such as wireline formation tests, closed chamber tests, production/reinjection tests and injection tests, as viable alternatives to conventional well testing. Results: While various short-term tests, test procedures and interpretation methods are apparently available for conducting successful tests without hydrocarbon production at the surface, clarity is lacking for specific applications of these techniques. An attempt to clarify advantages and limitations of each methodology, particularly with respect to the main testing target is pursued in this study. Specific insight is provided on injection testing, which is one of the most promising methodology to replace traditional well testing in reservoir characterization, except for the possibility to sample the formation fluids. Conclusion/Recommendations: Not a single one method but a combination of more methodologies, in particular injection testing and wireline formation testing, is the most promising

  11. Study on emissions reduction of DMCC engine with oxidation catalyst

    Institute of Scientific and Technical Information of China (English)

    YAO Chunde; LIU Xibo; WANG Hongfu; LIU Xiaoping; CHENG Chuanhui; WANG Yinshan

    2007-01-01

    A new combustion model diesel/methanol compound combustion (DMCC) is presented,in which methanol is injected into manifold and ignited by certain amount of diesel fuel.The results showed that DMCC remarkably decreased the emission of NOx and the smoke,but increased the emission of HC,CO and PM.However,HC,CO and NOx were dramatically decreased with a catalytic converter,and PM was also decreased compared with that of diesel engine.The testing results illustrated that,combined with oxidation catalyst converter,DMCC could improve engine emissions.

  12. Performance assessment of HC-290 as a drop-in substitute to HCFC-22 in a window air conditioner

    Energy Technology Data Exchange (ETDEWEB)

    Devotta, S. [National Environmental Engineering Research Institute, Nagpur (India); Padalkar, A.S. [National Chemical Laboratory, Pune (India). Process Development Division; Sane, N.K. [Walchand College of Engineering, Sangli (India). Department of Mechanical Engineering

    2005-06-01

    As per the Montreal Protocol, CFCs and HCFCs are being phased out. HCFC-22 is used in window air conditioners. This paper presents the experimental performance study of a window air conditioner with propane (HC-290), a natural refrigerant, as a drop-in substitute to HCFC-22. Experimental results showed that HC-290 had 6.6% lower cooling capacity for the lower operating conditions and 9.7% lower for the higher operating conditions with respect to HCFC-22. The coefficient of performance for HC-290 was 7.9% higher for the lower operating conditions and 2.8% higher for the higher operating conditions. The energy consumption of the unit with HC-290 was lower in the range 12.4-13.5% than HCFC-22. The discharge pressures for HC-290 were lower in the range 13.7-18.2% than HCFC-22. For HC-290, the pressure drop was lower than HCFC-22 in both heat exchangers. This paper also presents simulation results for the heat exchangers of an HCFC-22 window air conditioner with HC-290 as a drop-in substitute. The simulation has been carried out using EVAP-COND, a heat exchanger model developed by NIST [National Institute of Standards and Technology. EVAP-COND: simulation models for finned-tube heat exchangers, Maryland, USA (2003). http://www2.bfrl.nist.gov/software/evap-cond/ [18

  13. Non-detection of HC11N towards TMC-1: constraining the chemistry of large carbon-chain molecules

    Science.gov (United States)

    Loomis, Ryan A.; Shingledecker, Christopher N.; Langston, Glen; McGuire, Brett A.; Dollhopf, Niklaus M.; Burkhardt, Andrew M.; Corby, Joanna; Booth, Shawn T.; Carroll, P. Brandon; Turner, Barry; Remijan, Anthony J.

    2016-12-01

    Bell et al. reported the first detection of the cyanopolyyne HC11N towards the cold dark cloud TMC-1; no subsequent detections have been reported towards any source. Additional observations of cyanopolyynes and other carbon-chain molecules towards TMC-1 have shown a log-linear trend between molecule size and column density, and in an effort to further explore the underlying chemical processes driving this trend, we have analysed Green Bank Telescope observations of HC9N and HC11N towards TMC-1. Although we find an HC9N column density consistent with previous values, HC11N is not detected and we derive an upper limit column density significantly below that reported in Bell et al. Using a state-of-the-art chemical model, we have investigated possible explanations of non-linearity in the column density trend. Despite updating the chemical model to better account for ion-dipole interactions, we are not able to explain the non-detection of HC11N, and we interpret this as evidence of previously unknown carbon-chain chemistry. We propose that cyclization reactions may be responsible for the depleted HC11N abundance, and that products of these cyclization reactions should be investigated as candidate interstellar molecules.

  14. Combustion, Performance, and Emission Evaluation of a Diesel Engine with Biodiesel Like Fuel Blends Derived From a Mixture of Pakistani Waste Canola and Waste Transformer Oils

    Directory of Open Access Journals (Sweden)

    Muhammad Qasim

    2017-07-01

    Full Text Available The aim of this work was to study the combustion, performance, and emission characteristics of a 5.5 kW four-stroke single-cylinder water-cooled direct-injection diesel engine operated with blends of biodiesel-like fuel (BLF15, BLF20 & BLF25 obtained from a 50:50 mixture of transesterified waste transformer oil (TWTO and waste canola oil methyl esters (WCOME with petroleum diesel. The mixture of the waste oils was named as biodiesel-like fuel (BLF.The engine fuelled with BLF blends was evaluated in terms of combustion, performance, and emission characteristics. FTIR analysis was carried out to know the functional groups in the BLF fuel. The experimental results revealed the shorter ignition delay and marginally higher brake specific fuel consumption (BSFC, brake thermal efficiency (BTE and exhaust gas temperature (EGT values for BLF blends as compared to diesel. The hydrocarbon (HC and carbon monoxide (CO emissions were decreased by 10.92–31.17% and 3.80–6.32%, respectively, as compared to those of diesel fuel. Smoke opacity was significantly reduced. FTIR analysis has confirmed the presence of saturated alkanes and halide groups in BLF fuel. In comparison to BLF20 and BLF25, the blend BLF15 has shown higher brake thermal efficiency and lower fuel consumption values. The HC, CO, and smoke emissions of BLF15 were found lower than those of petroleum diesel. The fuel blend BLF15 is suggested to be used as an alternative fuel for diesel engines without any engine modification.

  15. Effect of hydroxy (HHO) gas addition on performance and exhaust emissions in compression ignition engines

    Energy Technology Data Exchange (ETDEWEB)

    Yilmaz, Ali Can; Uludamar, Erinc; Aydin, Kadir [Department of Mechanical Engineering, Cukurova University, 01330 Adana (Turkey)

    2010-10-15

    In this study, hydroxy gas (HHO) was produced by the electrolysis process of different electrolytes (KOH{sub (aq)}, NaOH{sub (aq)}, NaCl{sub (aq)}) with various electrode designs in a leak proof plexiglass reactor (hydrogen generator). Hydroxy gas was used as a supplementary fuel in a four cylinder, four stroke, compression ignition (CI) engine without any modification and without need for storage tanks. Its effects on exhaust emissions and engine performance characteristics were investigated. Experiments showed that constant HHO flow rate at low engine speeds (under the critical speed of 1750 rpm for this experimental study), turned advantages of HHO system into disadvantages for engine torque, carbon monoxide (CO), hydrocarbon (HC) emissions and specific fuel consumption (SFC). Investigations demonstrated that HHO flow rate had to be diminished in relation to engine speed below 1750 rpm due to the long opening time of intake manifolds at low speeds. This caused excessive volume occupation of hydroxy in cylinders which prevented correct air to be taken into the combustion chambers and consequently, decreased volumetric efficiency was inevitable. Decreased volumetric efficiency influenced combustion efficiency which had negative effects on engine torque and exhaust emissions. Therefore, a hydroxy electronic control unit (HECU) was designed and manufactured to decrease HHO flow rate by decreasing voltage and current automatically by programming the data logger to compensate disadvantages of HHO gas on SFC, engine torque and exhaust emissions under engine speed of 1750 rpm. The flow rate of HHO gas was measured by using various amounts of KOH, NaOH, NaCl (catalysts). These catalysts were added into the water to diminish hydrogen and oxygen bonds and NaOH was specified as the most appropriate catalyst. It was observed that if the molality of NaOH in solution exceeded 1% by mass, electrical current supplied from the battery increased dramatically due to the too much

  16. Source apportionment of hydrocarbons measured in the Eagle Ford shale

    Science.gov (United States)

    Roest, G. S.; Schade, G. W.

    2016-12-01

    The rapid development of unconventional oil and gas in the US has led to hydrocarbon emissions that are yet to be accurately quantified. Emissions from the Eagle Ford Shale in southern Texas, one of the most productive shale plays in the U.S., have received little attention due to a sparse air quality monitoring network, thereby limiting studies of air quality within the region. We use hourly atmospheric hydrocarbon and meteorological data from three locations in the Eagle Ford Shale to assess their sources. Data are available from the Texas commission of environmental quality (TCEQ) air quality monitors in Floresville, a small town southeast of San Antonio and just north of the shale area; and Karnes city, a midsize rural city in the center of the shale. Our own measurements were carried out at a private ranch in rural Dimmit County in southern Texas from April to November of 2015. Air quality monitor data from the TCEQ were selected for the same time period. Non-negative matrix factorization in R (package NMF) was used to determine likely sources and their contributions above background. While the TCEQ monitor data consisted mostly of hydrocarbons, our own data include both CO, CO2, O3, and NOx. We find that rural Dimmit County hydrocarbons are dominated by oil and gas development sources, while central shale hydrocarbons at the TCEQ monitoring sites have a mix of sources including car traffic. However, oil and gas sources also dominate hydrocarbons at Floresville and Karnes City. Toxic benzene is nearly exclusively due to oil and gas development sources, including flaring, which NMF identifies as a major hydrocarbon source in Karnes City. Other major sources include emissions of light weight alkanes (C2-C5) from raw natural gas emissions and a larger set of alkanes (C2-C10) from oil sources, including liquid storage tanks.

  17. KEYBOARD DESIGNING AND PROGRAMMING BASED ON M68HC08 SERIAL MCU%基于M68HC08系列单片机的键盘设计与编程

    Institute of Scientific and Technical Information of China (English)

    王宜怀; 王林; 张志平

    2001-01-01

    In this paper, the programming method of keyboard interrupt module for Motorola M68HC08 serial MCU is discussed. A design example about keyboard interface circuit based on MC68HC908GP32 MCU is given, and keyboard identification, the definition value of key, keyboard interrupt programming method are discussed.%讨论Motorola的新一代单片机M68HC08系列的键盘中断模块的编程方法,给出了一个基于MC68HC08GP32单片机的键盘接口电路设计实例,讨论了键的识别、键值定义、键盘中断等功能子程序的编制方法。

  18. COMPOSITIVE EMISSION CONTROL SYSTEM OF GASOLINE VEHICLE

    Institute of Scientific and Technical Information of China (English)

    CAI Ruibin; CHEN Zijian

    2006-01-01

    The working principle of a kind of compositive emission control system is inquired into,which includes exhaust heater, secondary air supplement, exhaust gas recirculation (EGR), thermal reactor and catalytic converter, etc. The purification effect of CO, HC and NOx emission of the gasoline spark ignite (S.I.) engine is studied. The entire vehicle driving cycle tests based on the national emission standard and a series of the gasoline engine-testing bench tests including full load characteristic experiment, load characteristic experiment and idle speed experiment are done. The results show that the system has a very good emission control effect to CO, HC and NOx of gasoline engine. The construction of the system is very simple and can be mounted on the exhaust pipe conveniently without any alteration of the vehicle-use gasoline engine.

  19. The effect of EGR rates on NOX and smoke emissions of an IDI diesel engine fuelled with Jatropha biodiesel blends

    Directory of Open Access Journals (Sweden)

    M. Gomaa, A.J. Alimin, K.A. Kamarudin

    2011-05-01

    Full Text Available The depletion of fossil fuels and the worst impact on environmental pollution caused of their burning have led to the search for renewable clean energies. Nowadays, there are many sources of renewable energy. Biodiesel is just one source, but a very important one. Biodiesel has been known as an attractive alternative fuel although biodiesel produced from edible oil is very expensive than conventional diesel. Therefore, the uses of biodiesel produced from non-edible oils are much better option. Currently Jatropha biodiesel (JBD is receiving attention as an alternative fuel for diesel engine. However, previous studies have reported that combustion of JBD emitted higher nitrogen oxides (NOX, while hydrocarbon (HC and smoke emissions were lower than conventional diesel fuel. Exhaust gas recirculation (EGR is one of the techniques being used to reduce NOX emission from diesel engines; because it decreases both flame temperature and oxygen concentration in the combustion chamber. Some studies succeeded to reduce NOX emission from biodiesel fuelled engines using EGR; but they observed increase in smoke emission with increasing engine load and EGR rate. The aim of the present work is to investigate the effect of EGR on an indirect injection (IDI diesel engine fuelled with JBD blends in order to reduce NOX and smoke emissions. A 4-cylinder, water-cooled, turbocharged, IDI diesel engine was used for investigation. Smoke, NOX, carbon monoxide (CO and carbon dioxide (CO2 emissions were recorded and various engine performance parameters were also evaluated. The results showed that, at 5% EGR with JB5, both NOX and smoke opacity were reduced by 27% and 17% respectively. Furthermore, JB20 along with 10% EGR was also able to reduce both NOX and smoke emission by 36% and 31%, respectively compared to diesel fuel without EGR.

  20. The 18-kilodalton Chlamydia trachomatis histone H1-like protein (Hc1) contains a potential N-terminal dimerization site and a C-terminal nucleic acid-binding domain

    DEFF Research Database (Denmark)

    Pedersen, Lotte Bang; Birkelund, S; Holm, A;

    1996-01-01

    , in part, be due to Hc1-mediated alterations of DNA topology. To locate putative functional domains within Hc1, polypeptides Hc1(2-57) and Hc1(53-125), corresponding to the N- and C-terminal parts of Hc1, respectively, were generated. By chemical cross-linking with ethylene glycol-bis (succinic acid N...

  1. ESTUDO TRIBOLÓGICO DE REVESTIMENTOS DE DLC COM GASES REFRIGERANTES HFC134A E HC600A

    National Research Council Canada - National Science Library

    Silverio, Marcio; Binder, Roberto; Mello, José Daniel Biasoli

    2011-01-01

    This work aims to study the effect of refrigerant gases HFC134a and HC600a in components coated with DLC, Diamond-like Carbon, as well as is to establish a methodology for tribology evaluating of them...

  2. Quantitative Hydrocarbon Surface Analysis

    Science.gov (United States)

    Douglas, Vonnie M.

    2000-01-01

    The elimination of ozone depleting substances, such as carbon tetrachloride, has resulted in the use of new analytical techniques for cleanliness verification and contamination sampling. The last remaining application at Rocketdyne which required a replacement technique was the quantitative analysis of hydrocarbons by infrared spectrometry. This application, which previously utilized carbon tetrachloride, was successfully modified using the SOC-400, a compact portable FTIR manufactured by Surface Optics Corporation. This instrument can quantitatively measure and identify hydrocarbons from solvent flush of hardware as well as directly analyze the surface of metallic components without the use of ozone depleting chemicals. Several sampling accessories are utilized to perform analysis for various applications.

  3. Miscellaneous hydrocarbon solvents.

    Science.gov (United States)

    Bebarta, Vikhyat; DeWitt, Christopher

    2004-08-01

    The solvents discussed in this article are common solvents not categorized as halogenated, aromatic, or botanical. The solvents discussed are categorized into two groups: hydrocarbon mixtures and single agents. The hydrocarbon mixtures discussed are Stoddard solvent, naphtha, and kerosene. The remaining solvents described are n-hexane, methyl n-butyl ketone, dimethylformamide, dimethyl sulfoxide, and butyl mercaptans. Effects common to this group of agents and their unique effects are characterized. Treatment of exposures and toxic effects of these solvents is described, and physiochemical properties and occupational exposure levels are listed.

  4. Genome-wide analysis of intracellular pH reveals quantitative control of cell division rate by pHc in Saccharomyces cerevisiae.

    NARCIS (Netherlands)

    Orij, R.; Urbanus, M.L.; Vizeacoumar, F.J.; Giaever, G.; Boone, C.; Nislow, C.; Brul, S.; Smits, G.J.

    2012-01-01

    ABSTRACT: BACKGROUND: Because protonation affects the properties of almost all molecules in cells, intracellular pH (pHc) is usually assumed to be constant. In the model organism yeast, however, pHc changes in response to the presence of nutrients and varies during growth. Since small changes in pHc

  5. Chemical composition of hydrocarbons from semicoking tars of lignites from the near-Moscow fields

    Energy Technology Data Exchange (ETDEWEB)

    Platonov, V.V.; Proskuryakov, V.A.; Antonio, T.Z.; Platonova, M.V. [Lev Tolstoi Pedagogical University, Tula (Russian Federation)

    1998-09-01

    The chemical composition of hydrocarbons from the semicoking tar of lignites was studied by elemental, functional, emission spectrum, and structural-group analyses, cryoscopy, IR, UV and {sup 1}H and {sup 13}C NMR spectroscopy, capillary gas chromatography, and gas chromatography-mass spectrometry. A scheme was developed for adsorption liquid chromatography of the hydrocarbons.

  6. Limitations of microbial hydrocarbon degradation at the Amon mud volcano (Nile deep-sea fan)

    NARCIS (Netherlands)

    Felden, J.; Lichtschlag, A.; Wenzhöfer, F.; de Beer, D.; Feseker, T.; Pop Ristova, P.; de Lange, G.; Boetius, A.

    2013-01-01

    The Amon mud volcano (MV), located at 1250m water depth on the Nile deep-sea fan, is known for its active emission of methane and non-methane hydrocarbons into the hydrosphere. Previous investigations showed a low efficiency of hydrocarbon-degrading anaerobic microbial communities inhabiting the Amo

  7. Lactogenic differentiation of HC11 cells is not accompanied by downregulation of AP-2 transcription factor genes

    Directory of Open Access Journals (Sweden)

    Schorle Hubert

    2008-06-01

    Full Text Available Abstract Background During pregnancy the mammary epithelium undergoes a complex developmental process which culminates in the generation of the milk-secreting epithelium. Secretory epithelial cells display lactogenic differentiation which is characterized by the expression of milk protein genes, such as beta-casein or whey acidic protein (WAP. Transcription factors AP-2alpha and AP-2gamma are downregulated during lactation, and their overexpression in transgenic mice impaired the secretory differentiation of the mammary epithelium, resulting in lactation failure. To explore whether the downregulation of AP-2alpha and AP-2gamma is of functional significance for lactogenic differentiation, we analyzed the expression of the AP-2 family members during the lactogenic differentiation of HC11 mammary epithelial cells in vitro. Differentiation of HC11 cells was induced following established protocols by applying the lactogenic hormones prolactin, dexamethasone and insulin. Findings HC11 cells express all AP-2 family members except AP-2delta. Using RT-PCR we could not detect a downregulation of any of these genes during the lactogenic differentiation of HC11 cells in vitro. This finding was confirmed for AP-2alpha and AP-2gamma using Northern analysis. Differentiating HC11 cells displayed lower expression levels of milk protein genes than mammary glands of mid-pregnant or lactating mice. Conclusion The extent of lactogenic differentiation of HC11 cells in vitro is limited compared to mammary epithelium undergoing secretory differentiation in vivo. Downregulation of AP-2 transcription factor genes is not required for lactogenic differentiation of HC11 cells but may functionally be involved in aspects of lactogenic differentiation in vivo that are not reflected by the HC11 system.

  8. Performance and specific emissions contours throughout the operating range of hydrogen-fueled compression ignition engine with diesel and RME pilot fuels

    Directory of Open Access Journals (Sweden)

    Shahid Imran

    2015-09-01

    Full Text Available This paper presents the performance and emissions contours of a hydrogen dual fueled compression ignition (CI engine with two pilot fuels (diesel and rapeseed methyl ester, and compares the performance and emissions iso-contours of diesel and rapeseed methyl ester (RME single fueling with diesel and RME piloted hydrogen dual fueling throughout the engines operating speed and power range. The collected data have been used to produce iso-contours of thermal efficiency, volumetric efficiency, specific oxides of nitrogen (NOX, specific hydrocarbons (HC and specific carbon dioxide (CO2 on a power-speed plane. The performance and emission maps are experimentally investigated, compared, and critically discussed. Apart from medium loads at lower and medium speeds with diesel piloted hydrogen combustion, dual fueling produced lower thermal efficiency everywhere across the map. For diesel and RME single fueling the maximum specific NOX emissions are centered at the mid speed, mid power region. Hydrogen dual fueling produced higher specific NOX with both pilot fuels as compared to their respective single fueling operations. The range, location and trends of specific NOX varied significantly when compared to single fueling cases. The volumetric efficiency is discussed in detail with the implications of manifold injection of hydrogen analyzed with the conclusions drawn.

  9. Experimental investigation of performance and emissions of a VCR diesel engine fuelled with n-butanol diesel blends under varying engine parameters.

    Science.gov (United States)

    Nayyar, Ashish; Sharma, Dilip; Soni, Shyam Lal; Mathur, Alok

    2017-07-13

    The continuous rise in the cost of fossil fuels as well as in environmental pollution has attracted research in the area of clean alternative fuels for improving the performance and emissions of internal combustion (IC) engines. In the present work, n-butanol is treated as a bio-fuel and investigations have been made to evaluate the feasibility of replacing diesel with a suitable n-butanol-diesel blend. In the current research, an experimental investigation was carried out on a variable compression ratio CI engine with n-butanol-diesel blends (10-25% by volume) to determine the optimum blending ratio and optimum operating parameters of the engine for reduced emissions. The best results of performance and emissions were observed for 20% n-butanol-diesel blend (B20) at a higher compression ratio as compared to diesel while keeping the other parameters unchanged. The observed deterioration in engine performance was within tolerable limits. The reductions in smoke, nitrogen oxides (NO x ), and carbon monoxide (CO) were observed up to 56.52, 17.19, and 30.43%, respectively, for B20 in comparison to diesel at rated power. However, carbon dioxide (CO2) and hydrocarbons (HC) were found to be higher by 17.58 and 15.78%, respectively, for B20. It is concluded that n-butanol-diesel blend would be a potential fuel to control emissions from diesel engines. Graphical abstract ᅟ.

  10. Performance of a split-type air conditioner matched with coiled adiabatic capillary tubes using HCFC22 and HC290

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Guobing [School of Energy and Power Engineering, North China Electric Power University, Beijing 102206 (China); Zhang, Yufeng [School of Environmental Science and Engineering, Tianjin University, Tianjin 300072 (China)

    2010-05-15

    This paper experimentally investigated the system performance of a split-type air conditioner matching with different coiled adiabatic capillary tubes for HCFC22 and HC290. Experiments were carried out in a room-type calorimeter. The results have shown that (1) similar cooling effects can be achieved by matching various capillary tubes of different inner diameters; (2) parallel capillary tubes presented better system performance and flow stability with weaker inlet pressure fluctuations than the single capillary tube; (3) with the coil diameter of the capillary tube increasing from 40 mm to 120 mm, the mass flow rate tended to increase slightly. But the cooling capacity, input power and energy efficiency ratio (EER) did not show evident tendency of change; (4) the refrigerant charge and mass flow rate for HC290 were only 44% and 47% of that for HCFC22, respectively, due to the much lower density. And HC290 had 4.7-6.7% lower cooling capacity and 12.1-12.3% lower input power with respect to HCFC22. However, the EER of HC290 can be 8.5% higher than that of HCFC22, which exhibits the advantage of using HC290. In addition, the experimental uncertainties were analyzed and some application concerns of HC290 were discussed. (author)

  11. Non-Detection of HC$_{11}$N toward TMC-1: Constraining the Chemistry of Large Carbon-Chain Molecules

    CERN Document Server

    Loomis, Ryan A; Langston, Glen; McGuire, Brett A; Dollhopf, Niklaus M; Burkhardt, Andrew M; Corby, Joanna; Booth, Shawn T; Carroll, P Brandon; Turner, Barry; Remijan, Anthony J

    2016-01-01

    Bell et al. (1997) reported the first detection of the cyanopolyyne HC$_{11}$N toward the cold dark cloud TMC-1; no subsequent detections have been reported toward any source. Additional observations of cyanopolyynes and other carbon-chain molecules toward TMC-1 have shown a log-linear trend between molecule size and column density, and in an effort to further explore the underlying chemical processes driving this trend, we have analyzed GBT observations of HC$_9$N and HC$_{11}$N toward TMC-1. Although we find an HC$_9$N column density consistent with previous values, HC$_{11}$N is not detected and we derive an upper limit column density significantly below that reported in Bell et al. Using a state-of-the-art chemical model, we have investigated possible explanations of non-linearity in the column density trend. Despite updating the chemical model to better account for ion-dipole interactions, we are not able to explain the non-detection of HC$_{11}$N, and we interpret this as evidence of previously unknown ...

  12. Studies on exhaust emissions of catalytic coated spark ignition engine with adulterated gasoline.

    Science.gov (United States)

    Muralikrishna, M V S; Kishor, K; Venkata Ramana Reddy, Ch

    2006-04-01

    Adulteration of automotive fuels, especially, gasoline with cheaper fuels is widespread throughout south Asia. Some adulterants decrease the performance and life of the engine and increase the emission of harmful pollutants causing environmental and health problems. The present investigation is carried out to study the exhaust emissions from a single cylinder spark ignition (SI) engine with kerosene blended gasoline with different versions of the engine, such as conventional engine and catalytic coated engine with different proportions of the kerosene ranging from 0% to 40% by volume in steps of 10% in the kerosene-gasoline blend. The catalytic coated engine used in the study has copper coating of thickness 400 microns on piston and inner surface of the cylinder head. The pollutants in the exhaust, carbon monoxide (CO) and unburnt hydrocarbons (UBHC) are measured with Netel Chromatograph CO and HC analyzer at peak load operation of the engine. The engine is provided with catalytic converter with sponge iron as a catalyst to control the pollutants from the exhaust of the engine. An air injection is also provided to the catalytic converter to further reduce the pollutants. The pollutants found to increase drastically with adulterated gasoline. Copper-coated engine with catalytic converter significantly reduced pollutants, when compared to conventional engine.

  13. The covalently bound HC tbnd N dimer ions HC dbnd N-N dbnd CH rad + and HC dbnd N-C( dbnd N)H rad + are stable species in the gas-phase, but the neutral counterparts are not

    Science.gov (United States)

    Jobst, Karl J.; Hanifa, M. Ruzni; Ruttink, Paul J. A.; Terlouw, Johan K.

    2009-05-01

    Tandem mass spectrometry based experiments and computational chemistry (CBS-QB3/APNO methods) indicate that ionized s-tetrazine eliminates N 2 to yield the elusive linear HC tbnd N dimer ion HC dbnd N-N dbnd CH rad + ( 1). The ion is stable in the rarefied gas-phase but, as it is generated with considerable internal energy, it readily interconverts with HC dbnd N-C( dbnd N)H rad + ( 2), via a 1,2-HCN shift. This more stable HCN dimer ion was generated independently by loss of HCN from ionized s-triazine. Whereas the HN tbnd C dimer ion HN dbnd C dbnd C dbnd NH rad + has a (kinetically) stable neutral counterpart, theory and experiment (neutralization-reionization mass spectrometry) agree that the HC tbnd N dimer ions 1 and 2 do not.

  14. Apparatus and methods for hydrocarbon extraction

    Science.gov (United States)

    Bohnert, George W.; Verhulst, Galen G.

    2016-04-26

    Systems and methods for hydrocarbon extraction from hydrocarbon-containing material. Such systems and methods relate to extracting hydrocarbon from hydrocarbon-containing material employing a non-aqueous extractant. Additionally, such systems and methods relate to recovering and reusing non-aqueous extractant employed for extracting hydrocarbon from hydrocarbon-containing material.

  15. JM47, a cyclic tetrapeptide HC-toxin analogue from a marine Fusarium species.

    Science.gov (United States)

    Jiang, Zhong; Barret, Marc-Olivier; Boyd, Kenneth G; Adams, David R; Boyd, Alan S F; Burgess, J Grant

    2002-05-01

    The known metabolite, enniatin B, and a cyclic tetrapeptide, JM47, which is a new natural product, were extracted from brown rice cultures of a marine fungus, identified as a Fusarium species, isolated from the marine alga Codium fragile. NMR studies, including 15N HMQC and 15N HMBC, established the structure of JM47 as cyclo(Ala-Ala-Aoh-Pro), where Aoh is the amino acid, (2S,9S)-2-amino-8-oxo-9-hydroxydecanoic acid. The absolute stereochemistry of the Aoh side chain carbinol centre was determined using Mosher ester methodology. Analysis of NOESY data assisted by molecular modelling revealed an alternating L-, D-, L-, D-configuration for the tetrapeptide core. The absolute stereochemistry of the core was determined by acidic hydrolysis and chiral TLC analysis of the proline residue. JM47 belongs to the HC-toxin family of cyclic tetrapeptides which possess a 2-amino-8-oxo-9,10-epoxydecanoic acid residue in place of the Aoh unit. This is the first report of an analogue of HC-toxin from a marine Fusarium species.

  16. Ext The effect of littoralis leaf extract on Hemolytic Value (HC50 of mice

    Directory of Open Access Journals (Sweden)

    Zhi-jiang WANG

    2013-12-01

    Full Text Available Objective: To study the effect of Umbelliferae littoralis leaf extract on the Hemolytic Value (HC50 of mice, and to provide the basis for the development and utilization medicinal resources and edible resources. Methods: Prepare littoralis leaf water extract and alcohol extract, and set different dose treatment groups and blank control group, and continuously deliver American ginseng capsule for 15 days. Inject sRBC according to the weight on the tenth day. Take the blood serum from eyeball blood after 5 days. Put supernatant of 1ml and Dulbecco's reagent of 3ml in the test tube, and mix the 10% sRBC of 0.25ml and Dulbecco's reagent of 4ml together in another test tube, and measure absorbance at 540nm fine control (SA liquid tubing as blank, HC50 value were calculated. Results: Different extracts of stems and littoralis leaf were given to the mice for 15 days, and hemolytic value of the mice in water extract 4.68g/kg dose group, alcohol extract 4.68g/kg dose group and American ginseng capsule group significantly increased while comparing with the blank control group (P<0.05. Conclusion: Littoralis Leaf plays an important role in regulating human immunity.

  17. Experimental evaluation of automotive air-conditioning using HFC-134a and HC-134a

    Science.gov (United States)

    Nasution, Henry; Zainudin, Muhammad Amir; Aziz, Azhar Abdul; Latiff, Zulkarnain Abdul; Perang, Mohd Rozi Mohd; Rahman, Abd Halim Abdul

    2012-06-01

    An experimental study to evaluate the energy consumption of an automotive air conditioning is presented. In this study, these refrigerants will be tested using the experimental rig which simulated the actual cars as a cabin complete with a cooling system component of the actual car that is as the blower, evaporator, condenser, radiators, electric motor, which acts as a vehicle engine, and then the electric motor will operate the compressor using a belt and pulley system, as well as to the alternator will recharge the battery. The compressor working with the fluids HFC-134a and HC-134a and has been tested varying the speed in the range 1000, 1500, 2000 and 2500 rpm. The measurements taken during the one hour experimental periods at 2-minutes interval times for temperature setpoint of 20°C with internal heat loads 0, 500, 700 and 1000 W. The final results of this study show an overall better energy consumption of the HFC-134a compared with the HC-134a.

  18. Mantle hydrocarbons: abiotic or biotic?

    Science.gov (United States)

    Sugisaki, R; Mimura, K

    1994-06-01

    Analyses of 227 rocks from fifty localities throughout the world showed that mantle derived rocks such as tectonized peridotites in ophiolite sequences (tectonites) arid peridotite xenoliths in alkali basalts contain heavier hydrocarbons (n-alkanes), whereas igneous rocks produced by magmas such as gabbro arid granite lack them. The occurrence of hydrocarbons indicates that they were not derived either from laboratory contamination or from held contamination; these compounds found in the mantle-derived rocks are called here "mantle hydrocarbons." The existence of hydrocarbons correlates with petrogenesis. For example, peridotite cumulates produced by magmatic differentiation lack hydrocarbons whereas peridotite xenoliths derived from the mantle contain them. Gas chromatographic-mass spectrometric records of the mantle hydrocarbons resemble those of aliphatics in meteorites and in petroleum. Features of the hydrocarbons are that (a) the mantle hydrocarbons reside mainly along grain boundaries and in fluid inclusions of minerals; (b) heavier isoprenoids such as pristane and phytane are present; and (c) delta 13C of the mantle hydrocarbons is uniform (about -27%). Possible origins for the mantle hydrocarbons are as follows. (1) They were in organically synthesized by Fischer-Tropsch type reaction in the mantle. (2) They were delivered by meteorites and comets to the early Earth. (3) They were recycled by subduction. The mantle hydrocarbons in the cases of (1) and (2) are abiogenic and those in (3) are mainly biogenic. It appears that hydrocarbons may survive high pressures and temperatures in the mantle, but they are decomposed into lighter hydrocarbon gases such as CH4 at lower pressures when magmas intrude into the crust; consequently, peridotite cumulates do not contain heavier hydrocarbons but possess hydrocarbon gases up to C4H10.

  19. CO and PAH emissions from engines operating on producer gas

    DEFF Research Database (Denmark)

    Ahrenfeldt, Jesper

    2005-01-01

    from the start been that a high CO emission is a measure for incomplete combustion of hydrocarbons and thus an indicator for the presents of organic micro emissions such as polynuclear aromatic hydrocarbons (PAH). Measurements from two operating gasification plants show that there is no correlation...... between the high CO emissions and PAH emissions from engines operating on producer gas. The measured PAH emissions were more than 20 times lower than the recommended emission limit for gas engines. Since unburned CO and UHC are similar in origin the reasonable regulated limit for CO emissions from engines...

  20. 40 CFR 1065.372 - NDUV analyzer HC and H2O interference verification.

    Science.gov (United States)

    2010-07-01

    ... this part. Use the FID response as the reference hydrocarbon value. (3) Upstream of any sample dryer... verification. 1065.372 Section 1065.372 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Calibrations and Verifications Nox and...

  1. Bacterial sources for phenylalkane hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Ellis, L.; Winans, R.E. [Argonne National Lab., IL (United States); Langworthy, T. [Univ. of South Dakota, Vermillion, SD (United States)

    1996-10-01

    The presence of phenylalkane hydrocarbons in geochemical samples has been the source of much controversy. Although an anthropogenic input from detergent sources always appears likely, the distribution of phenylalkane hydrocarbons in some cases far exceeding that attributed to detergent input has led to a reappraisal of this view. Indeed, recent work involving analysis of the lipid hydrocarbon extracts from extant Thermoplasma bacteria has revealed the presence of phenylalkane hydrocarbons. The presence of phenylalkane hydrocarbons in sedimentary organic matter may therefore represent potential biological markers for thermophilic bacteria.

  2. Methane Decomposition and C2 Hydrocarbon Formation under the Condition of DC Discharge Plasma

    Institute of Scientific and Technical Information of China (English)

    Jianxun He; Miao Hu; Zhiguo Lu

    2004-01-01

    The infrared emission spectra of methane, H, CH and C2 hydrocarbons in natural gas were measured. The processes of methane decomposition and formation of C2 hydrocarbons were studied. The experiment shows that methane decomposition can be divided into three periods as the reaction proceeds.In the first period, a large number of free radicals were formed. While in the last period, the formation of C2 hydrocarbons and the decrease of free radicals were observed. The time and conditions of methane decomposition and formation of C2 hydrocarbons are different.

  3. Multifunctional cellulolytic auxiliary activity protein HcAA10-2 from Hahella chejuensis enhances enzymatic hydrolysis of crystalline cellulose.

    Science.gov (United States)

    Ghatge, Sunil S; Telke, Amar A; Waghmode, Tatoba R; Lee, Yuno; Lee, Keun-Woo; Oh, Doo-Byoung; Shin, Hyun-Dong; Kim, Seon-Won

    2015-04-01

    The modular auxiliary activity (AA) family of proteins is believed to cause amorphogenesis in addition to oxidative cleavage of crystalline cellulose although the supporting evidence is limited. HcAA10-2 is a modular AA10 family protein (58 kDa) composed of a AA10 module and a family two carbohydrate binding module (CBM2), joined by a long stretch of 222 amino acids of unknown function. The protein was expressed in Escherichia coli and purified to homogeneity. Scanning electron microscopy and X-ray diffraction analysis of Avicel treated with HcAA10-2 provided evidence for the disruption of the cellulose microfibrils ("amorphogenesis") and reduction of the crystallinity index, resulting in a twofold increase of cellulase adsorption on the polysaccharide surface. HcAA10-2 exhibited weak endoglucanase-like activity toward soluble cellulose and cello-oligosaccharides with an optimum at pH 6.5 and 45 °C. HcAA10-2 catalyzed oxidative cleavage of crystalline cellulose released native and oxidized cello-oligosaccharides in the presence of copper and an electron donor such as ascorbic acid. Multiple sequence alignment indicated that His1, His109, and Phe197 in the AA10 module formed the conserved copper-binding site. The reducing sugar released from Avicel by the endoglucanase Cel5 and Celluclast accompanying HcAA10-2 was increased by four- and sixfold, respectively. Moreover, HcAA10-2 and Celluclast acted synergistically on pretreated wheat straw biomass resulting in a threefold increase in reducing sugar than Celluclast alone. Taken together, these results suggest that HcAA10-2 is a novel multifunctional modular AA10 protein possessing amorphogenesis, weak endoglucanase, and oxidative cleavage activities useful for efficient degradation of crystalline cellulose.

  4. Tetanus Toxin Hc Fragment Induces the Formation of Ceramide Platforms and Protects Neuronal Cells against Oxidative Stress.

    Directory of Open Access Journals (Sweden)

    Roger Cubí

    Full Text Available Tetanus toxin (TeTx is the protein, synthesized by the anaerobic bacteria Clostridium tetani, which causes tetanus disease. TeTx gains entry into target cells by means of its interaction with lipid rafts, which are membrane domains enriched in sphingomyelin and cholesterol. However, the exact mechanism of host membrane binding remains to be fully established. In the present study we used the recombinant carboxyl terminal fragment from TeTx (Hc-TeTx, the domain responsible for target neuron binding, showing that Hc-TeTx induces a moderate but rapid and sustained increase in the ceramide/sphingomyelin ratio in primary cultures of cerebellar granule neurons and in NGF-differentiated PC12 cells, as well as induces the formation of ceramide platforms in the plasma membrane. The mentioned increase is due to the promotion of neutral sphingomyelinase activity and not to the de novo synthesis, since GW4869, a specific neutral sphingomyelinase inhibitor, prevents neutral sphingomyelinase activity increase and formation of ceramide platforms. Moreover, neutral sphingomyelinase inhibition with GW4869 prevents Hc-TeTx-triggered signaling (Akt phosphorylation, as well as the protective effect of Hc-TeTx on PC12 cells subjected to oxidative stress, while siRNA directed against nSM2 prevents protection by Hc-TeTx of NSC-34 cells against oxidative insult. Finally, neutral sphingomyelinase activity seems not to be related with the internalization of Hc-TeTx into PC12 cells. Thus, the presented data shed light on the mechanisms triggered by TeTx after membrane binding, which could be related with the events leading to the neuroprotective action exerted by the Hc-TeTx fragment.

  5. Microbial degradation of petroleum hydrocarbons.

    Science.gov (United States)

    Varjani, Sunita J

    2017-01-01

    Petroleum hydrocarbon pollutants are recalcitrant compounds and are classified as priority pollutants. Cleaning up of these pollutants from environment is a real world problem. Bioremediation has become a major method employed in restoration of petroleum hydrocarbon polluted environments that makes use of natural microbial biodegradation activity. Petroleum hydrocarbons utilizing microorganisms are ubiquitously distributed in environment. They naturally biodegrade pollutants and thereby remove them from the environment. Removal of petroleum hydrocarbon pollutants from environment by applying oleophilic microorganisms (individual isolate/consortium of microorganisms) is ecofriendly and economic. Microbial biodegradation of petroleum hydrocarbon pollutants employs the enzyme catalytic activities of microorganisms to enhance the rate of pollutants degradation. This article provides an overview about bioremediation for petroleum hydrocarbon pollutants. It also includes explanation about hydrocarbon metabolism in microorganisms with a special focus on new insights obtained during past couple of years. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Superconductivity in aromatic hydrocarbons

    Energy Technology Data Exchange (ETDEWEB)

    Kubozono, Yoshihiro, E-mail: kubozono@cc.okayama-u.ac.jp [Research Laboratory for Surface Science, Okayama University, Okayama 700-8530 (Japan); Research Center of New Functional Materials for Energy Production, Storage and Transport, Okayama University, Okayama 700-8530 (Japan); Japan Science and Technology Agency, ACT-C, Kawaguchi 332-0012 (Japan); Goto, Hidenori; Jabuchi, Taihei [Research Laboratory for Surface Science, Okayama University, Okayama 700-8530 (Japan); Yokoya, Takayoshi [Research Laboratory for Surface Science, Okayama University, Okayama 700-8530 (Japan); Research Center of New Functional Materials for Energy Production, Storage and Transport, Okayama University, Okayama 700-8530 (Japan); Kambe, Takashi [Department of Physics, Okayama University, Okayama 700-8530 (Japan); Sakai, Yusuke; Izumi, Masanari; Zheng, Lu; Hamao, Shino; Nguyen, Huyen L.T. [Research Laboratory for Surface Science, Okayama University, Okayama 700-8530 (Japan); Sakata, Masafumi; Kagayama, Tomoko; Shimizu, Katsuya [Center of Science and Technology under Extreme Conditions, Osaka University, Osaka 560-8531 (Japan)

    2015-07-15

    Highlights: • Aromatic superconductor is one of core research subjects in superconductivity. Superconductivity is observed in certain metal-doped aromatic hydrocarbons. Some serious problems to be solved exist for future advancement of the research. This article shows the present status of aromatic superconductors. - Abstract: ‘Aromatic hydrocarbon’ implies an organic molecule that satisfies the (4n + 2) π-electron rule and consists of benzene rings. Doping solid aromatic hydrocarbons with metals provides the superconductivity. The first discovery of such superconductivity was made for K-doped picene (K{sub x}picene, five benzene rings). Its superconducting transition temperatures (T{sub c}’s) were 7 and 18 K. Recently, we found a new superconducting K{sub x}picene phase with a T{sub c} as high as 14 K, so we now know that K{sub x}picene possesses multiple superconducting phases. Besides K{sub x}picene, we discovered new superconductors such as Rb{sub x}picene and Ca{sub x}picene. A most serious problem is that the shielding fraction is ⩽15% for K{sub x}picene and Rb{sub x}picene, and it is often ∼1% for other superconductors. Such low shielding fractions have made it difficult to determine the crystal structures of superconducting phases. Nevertheless, many research groups have expended a great deal of effort to make high quality hydrocarbon superconductors in the five years since the discovery of hydrocarbon superconductivity. At the present stage, superconductivity is observed in certain metal-doped aromatic hydrocarbons (picene, phenanthrene and dibenzopentacene), but the shielding fraction remains stubbornly low. The highest priority research area is to prepare aromatic superconductors with a high superconducting volume-fraction. Despite these difficulties, aromatic superconductivity is still a core research target and presents interesting and potentially breakthrough challenges, such as the positive pressure dependence of T{sub c} that is clearly

  7. Geofluid dynamic concept of hydrocarbon accumulation in natural reservoirs

    Science.gov (United States)

    Kerimov, V. Yu.; Rachinsky, M. Z.

    2016-11-01

    Most modern theories axiomatically assume that hydrocarbons (HCs), which migrate in different ways from the generation zones and sources with high gradients of reduced pressures, concentrate in autochthonous natural reservoirs possessing smaller levels of reservoir energy. Hydraulic drainage of reservoirs is possible in principle through only three mechanisms: (i) horizontally oriented regional elisional water flow upwards, along the plunge of general folding from central parts of basins towards their peripheral frames; (ii) owing to the effect of lateral pressure of groundwater immediately in traps, with subsequent pushing out by high-pressure fluids supplied to the sunken parts of folds; (iii) vertically directed, from bottom to top, overflow injection mechanism. The study of their possible implementations and relative ratios in the outcome comprise the content of the proposed fluid-dynamic concept of HC accumulation.

  8. On-board gaseous emissions of LPG taxis and estimation of taxi fleet emissions.

    Science.gov (United States)

    Lau, Jason; Hung, W T; Cheung, C S

    2011-11-15

    Instantaneous CO, NO, and HC emissions and exhaust flow rates from four LPG taxis, which adhered to Euro 2-4 emission standards, were measured using a sophisticated portable emission measurement system (PEMS). Instantaneous air/fuel ratios, emission rates, and emission factors at different operating modes were derived to explore the emission characteristics of these four taxis. Results show that gaseous emissions from these four taxis exceed emission standards, due to extended vehicle use and poor maintenance. NO emissions from newer taxis are lower whilst CO and HC emissions of the Euro 4 taxi are similar to those of Euro 2 taxis during idling and low speed travel. The taxis emit lower amounts of gaseous pollutants whilst idling and emit the highest amounts of CO and NO whilst accelerating. Large fluctuations in air/fuel ratios can be observed from the Euro 4 taxi during idling, indicating a malfunction of fuel supply control to the engine. Such fluctuations are not observed from the other taxis. This shows that a Euro 4 taxi is not necessarily cleaner than a Euro 3 taxi. Emission factors derived from on-board measurements are applied to estimate gaseous emissions from the taxi fleet; these results show that emissions are higher during peak hour traffic conditions. An estimate of the taxi fleet's emissions whilst the older taxis are replaced is also calculated. It can be seen that faster replacement of older taxis can lead to reductions in gaseous emissions from the taxi fleet. This study shows that the PEMS is an adequate tool for measuring emissions from LPG vehicles and that there is an urgent need to enforce emission standards on taxis. This study also shows that on-board measurements should be incorporated in the estimation of emissions from other vehicle types. This would result in better emission estimations under local traffic conditions. Copyright © 2011 Elsevier B.V. All rights reserved.

  9. Calculation of odour emissions from aircraft engines at Copenhagen Airport.

    Science.gov (United States)

    Winther, Morten; Kousgaard, Uffe; Oxbøl, Arne

    2006-07-31

    In a new approach the odour emissions from aircraft engines at Copenhagen Airport are calculated using actual fuel flow and emission measurements (one main engine and one APU: Auxiliary Power Unit), odour panel results, engine specific data and aircraft operational data for seven busy days. The calculation principle assumes a linear relation between odour and HC emissions. Using a digitalisation of the aircraft movements in the airport area, the results are depicted on grid maps, clearly reflecting aircraft operational statistics as single flights or total activity during a whole day. The results clearly reflect the short-term temporal fluctuations of the emissions of odour (and exhaust gases). Aircraft operating at low engine thrust (taxiing, queuing and landing) have a total odour emission share of almost 98%, whereas the shares for the take off/climb out phases (2%) and APU usage (0.5%) are only marginal. In most hours of the day, the largest odour emissions occur, when the total amount of fuel burned during idle is high. However, significantly higher HC emissions for one specific engine cause considerable amounts of odour emissions during limited time periods. The experimentally derived odour emission factor of 57 OU/mg HC is within the range of 23 and 110 OU/mg HC used in other airport odour studies. The distribution of odour emission results between aircraft operational phases also correspond very well with the results for these other studies. The present study uses measurement data for a representative engine. However, the uncertainties become large when the experimental data is used to estimate the odour emissions for all aircraft engines. More experimental data is needed to increase inventory accuracy, and in terms of completeness it is recommended to make odour emission estimates also for engine start and the fuelling of aircraft at Copenhagen Airport in the future.

  10. Membrane separation of hydrocarbons

    Science.gov (United States)

    Chang, Y. Alice; Kulkarni, Sudhir S.; Funk, Edward W.

    1986-01-01

    Mixtures of heavy oils and light hydrocarbons may be separated by passing the mixture through a polymeric membrane. The membrane which is utilized to effect the separation comprises a polymer which is capable of maintaining its integrity in the presence of hydrocarbon compounds and which has been modified by being subjected to the action of a sulfonating agent. Sulfonating agents which may be employed will include fuming sulfuric acid, chlorosulfonic acid, sulfur trioxide, etc., the surface or bulk modified polymer will contain a degree of sulfonation ranging from about 15 to about 50%. The separation process is effected at temperatures ranging from about ambient to about 100.degree. C. and pressures ranging from about 50 to about 1000 psig.

  11. Molecular structure, chemical synthesis, and antibacterial activity of ABP-dHC-cecropin A from drury (Hyphantria cunea).

    Science.gov (United States)

    Zhang, Jiaxin; Movahedi, Ali; Wang, Xiaoli; Wu, Xiaolong; Yin, Tongming; Zhuge, Qiang

    2015-06-01

    The increasing resistance of bacteria and fungi to currently available antibiotics is a major concern worldwide, leading to enormous efforts to develop new antibiotics with new modes of actions. In this paper, cDNA encoding cecropin A was amplified from drury (Hyphantria cunea) (dHC) pupa fatbody total RNA using RT-PCR. The full-length dHC-cecropin A cDNA encoded a protein of 63 amino acids with a predicted 26-amino acid signal peptide and a 37-amino acid functional domain. We synthesized the antibacterial peptide (ABP) from the 37-amino acid functional domain (ABP-dHC-cecropin A), and amidated it via the C-terminus. Time-of-flight mass spectrometry showed its molecular weight to be 4058.94. The ABP-dHC-cecropin A was assessed in terms of its protein structure using bioinformatics and CD spectroscopy. The protein's secondary structure was predicted to be α-helical. In an antibacterial activity analysis, the ABP-dHC-cecropin A exhibited strong antibacterial activity against E. coli K12D31 and Agrobacterium EHA105. Copyright © 2014 Elsevier Inc. All rights reserved.

  12. a Search for Interstellar Carbon-Chain Alcohol HC4OH in the Star Forming Region L1527

    Science.gov (United States)

    Araki, Mitsunori; Takano, Shuro; Koshikawa, Hiromichi Yamabe Naohiro; Tsukiyama, Koichi; Nakane, Aya; Okabatyashi, Toshiaki; Kunimatsu, Arisa; Kuze, Nobuhiko

    2011-06-01

    We have made a sensitive search for the rotational transitions of carbon-chain alcohol HC_4OH with the frequency ragne from 21.2 to 46.7 GHz in the star forming region L1527 in Taurus with rich carbon-chain chemistry. The incentive of this observation was a laboratory detection of HC_4OH by the microwave spectroscopy. Despite achieving an rms of several mK in antenna temperature by the 45m telescope at Nobeyama Radio Observatory, the searche for HC_4OH was negative, leading to a 5 sigma upper limit corresponding to the column density of 4 × 1012 Cm-2 based on the excitation temperature of 12.3 K. The upper limit indicates that the [HC_4-OH]/[HC_4-CN] ratio is less than 1.0. The ratio suggests that the cyanide species with carbon-chain structure is dominant in comparison with the hydroxyl one in L1527, which can be the opposite case of saturated compounds, e.g. CH_3OH and CH_3CN, in hot cores and dark clouds.

  13. Heterodimerization of y(+)LAT-1 and 4F2hc visualized by acceptor photobleaching FRET microscopy.

    Science.gov (United States)

    Kleemola, Maaria; Toivonen, Minna; Mykkänen, Juha; Simell, Olli; Huoponen, Kirsi; Heiskanen, Kaisa M

    2007-10-01

    y(+)LAT-1 and 4F2hc are the subunits of a transporter complex for cationic amino acids, located mainly in the basolateral plasma membrane of epithelial cells in the small intestine and renal tubules. Mutations in y(+)LAT-1 impair the transport function of this complex and cause a selective aminoaciduria, lysinuric protein intolerance (LPI, OMIM #222700), associated with severe, complex clinical symptoms. The subunits of an active transporter co-localize in the plasma membrane, but the exact process of dimerization is unclear since direct evidence for the assembly of this transporter in intact human cells has not been available. In this study, we used fluorescence resonance energy transfer (FRET) microscopy to investigate the interactions of y(+)LAT-1 and 4F2hc in HEK293 cells expressing y(+)LAT-1 and 4F2hc fused with ECFP or EYFP. FRET was quantified by measuring fluorescence intensity changes in the donor fluorophore (ECFP) after the photobleaching of the acceptor (EYFP). Increased donor fluorescence could be detected throughout the cell, from the endoplasmic reticulum and Golgi complex to the plasma membrane. Therefore, our data prove the interaction of y(+)LAT-1 and 4F2hc prior to the plasma membrane and thus provide evidence for 4F2hc functioning as a chaperone in assisting the transport of y(+)LAT-1 to the plasma membrane.

  14. Influences of Catalytic Combustion on the Ignition Timing and Emissions of HCCI Engines

    Institute of Scientific and Technical Information of China (English)

    ZENG Wen; XIE Mao-zhao

    2008-01-01

    The combustion processes of homogeneous charge compression ignition (HCCI) engines whose piston surfaces have been coated with catalyst (rhodium or platinum) were numerically investigated. A single-zone model and a multi-zone model were developed. The effects of catalytic combustion on the ignition timing of the HCCI engine were analyzed through the single-zone model. The results showed that the ignition timing of the HCCI engine was advanced by the catalysis. The effects of catalytic combustion on HC, CO and NOx emissions of the HCCI engine were analyzed through the multi-zone model. The results showed that the emissions of HC and CO (using platinum (Pt) as catalyst) were decreased, while the emissions of NOx were elevated by catalytic combustion. Compared with catalyst Pt, the HC emissions were lower with catalyst rhodium(Rh) on the piston surface, but the emissions of NOx and CO were higher.

  15. Observation of hc Radiative Decay hc→γ η' and Evidence for hc→γ η

    Science.gov (United States)

    Ablikim, M.; Achasov, M. N.; Ai, X. C.; Albayrak, O.; Albrecht, M.; Ambrose, D. J.; Amoroso, A.; An, F. F.; An, Q.; Bai, J. Z.; Baldini Ferroli, R.; Ban, Y.; Bennett, D. W.; Bennett, J. V.; Bertani, M.; Bettoni, D.; Bian, J. M.; Bianchi, F.; Boger, E.; Boyko, I.; Briere, R. A.; Cai, H.; Cai, X.; Cakir, O.; Calcaterra, A.; Cao, G. F.; Cetin, S. A.; Chang, J. F.; Chelkov, G.; Chen, G.; Chen, H. S.; Chen, H. Y.; Chen, J. C.; Chen, M. L.; Chen, S.; Chen, S. J.; Chen, X.; Chen, X. R.; Chen, Y. B.; Cheng, H. P.; Chu, X. K.; Cibinetto, G.; Dai, H. L.; Dai, J. P.; Dbeyssi, A.; Dedovich, D.; Deng, Z. Y.; Denig, A.; Denysenko, I.; Destefanis, M.; de Mori, F.; Ding, Y.; Dong, C.; Dong, J.; Dong, L. Y.; Dong, M. Y.; Dou, Z. L.; Du, S. X.; Duan, P. F.; Fan, J. Z.; Fang, J.; Fang, S. S.; Fang, X.; Fang, Y.; Farinelli, R.; Fava, L.; Fedorov, O.; Feldbauer, F.; Felici, G.; Feng, C. Q.; Fioravanti, E.; Fritsch, M.; Fu, C. D.; Gao, Q.; Gao, X. L.; Gao, X. Y.; Gao, Y.; Gao, Z.; Garzia, I.; Goetzen, K.; Gong, L.; Gong, W. X.; Gradl, W.; Greco, M.; Gu, M. H.; Gu, Y. T.; Guan, Y. H.; Guo, A. Q.; Guo, L. B.; Guo, R. P.; Guo, Y.; Guo, Y. P.; Haddadi, Z.; Hafner, A.; Han, S.; Hao, X. Q.; Harris, F. A.; He, K. L.; Held, T.; Heng, Y. K.; Hou, Z. L.; Hu, C.; Hu, H. M.; Hu, J. F.; Hu, T.; Hu, Y.; Huang, G. S.; Huang, J. S.; Huang, X. T.; Huang, X. Z.; Huang, Y.; Huang, Z. L.; Hussain, T.; Ji, Q.; Ji, Q. P.; Ji, X. B.; Ji, X. L.; Jiang, L. W.; Jiang, X. S.; Jiang, X. Y.; Jiao, J. B.; Jiao, Z.; Jin, D. P.; Jin, S.; Johansson, T.; Julin, A.; Kalantar-Nayestanaki, N.; Kang, X. L.; Kang, X. S.; Kavatsyuk, M.; Ke, B. C.; Kiese, P.; Kliemt, R.; Kloss, B.; Kolcu, O. B.; Kopf, B.; Kornicer, M.; Kupsc, A.; Kühn, W.; Lange, J. S.; Lara, M.; Larin, P.; Leng, C.; Li, C.; Li, Cheng; Li, D. M.; Li, F.; Li, F. Y.; Li, G.; Li, H. B.; Li, H. J.; Li, J. C.; Li, Jin; Li, K.; Li, K.; Li, Lei; Li, P. R.; Li, Q. Y.; Li, T.; Li, W. D.; Li, W. G.; Li, X. L.; Li, X. N.; Li, X. Q.; Li, Y. B.; Li, Z. B.; Liang, H.; Liang, Y. F.; Liang, Y. T.; Liao, G. R.; Lin, D. X.; Liu, B.; Liu, B. J.; Liu, C. X.; Liu, D.; Liu, F. H.; Liu, Fang; Liu, Feng; Liu, H. B.; Liu, H. H.; Liu, H. H.; Liu, H. M.; Liu, J.; Liu, J. B.; Liu, J. P.; Liu, J. Y.; Liu, K.; Liu, K. Y.; Liu, L. D.; Liu, P. L.; Liu, Q.; Liu, S. B.; Liu, X.; Liu, Y. B.; Liu, Z. A.; Liu, Zhiqing; Loehner, H.; Lou, X. C.; Lu, H. J.; Lu, J. G.; Lu, Y.; Lu, Y. P.; Luo, C. L.; Luo, M. X.; Luo, T.; Luo, X. L.; Lyu, X. R.; Ma, F. C.; Ma, H. L.; Ma, L. L.; Ma, M. M.; Ma, Q. M.; Ma, T.; Ma, X. N.; Ma, X. Y.; Ma, Y. M.; Maas, F. E.; Maggiora, M.; Mao, Y. J.; Mao, Z. P.; Marcello, S.; Messchendorp, J. G.; Min, J.; Mitchell, R. E.; Mo, X. H.; Mo, Y. J.; Morales Morales, C.; Muchnoi, N. Yu.; Muramatsu, H.; Nefedov, Y.; Nerling, F.; Nikolaev, I. B.; Ning, Z.; Nisar, S.; Niu, S. L.; Niu, X. Y.; Olsen, S. L.; Ouyang, Q.; Pacetti, S.; Pan, Y.; Patteri, P.; Pelizaeus, M.; Peng, H. P.; Peters, K.; Pettersson, J.; Ping, J. L.; Ping, R. G.; Poling, R.; Prasad, V.; Qi, H. R.; Qi, M.; Qian, S.; Qiao, C. F.; Qin, L. Q.; Qin, N.; Qin, X. S.; Qin, Z. H.; Qiu, J. F.; Rashid, K. H.; Redmer, C. F.; Ripka, M.; Rong, G.; Rosner, Ch.; Ruan, X. D.; Sarantsev, A.; Savrié, M.; Schoenning, K.; Schumann, S.; Shan, W.; Shao, M.; Shen, C. P.; Shen, P. X.; Shen, X. Y.; Sheng, H. Y.; Shi, M.; Song, W. M.; Song, X. Y.; Sosio, S.; Spataro, S.; Sun, G. X.; Sun, J. F.; Sun, S. S.; Sun, X. H.; Sun, Y. J.; Sun, Y. Z.; Sun, Z. J.; Sun, Z. T.; Tang, C. J.; Tang, X.; Tapan, I.; Thorndike, E. H.; Tiemens, M.; Ullrich, M.; Uman, I.; Varner, G. S.; Wang, B.; Wang, B. L.; Wang, D.; Wang, D. Y.; Wang, K.; Wang, L. L.; Wang, L. S.; Wang, M.; Wang, P.; Wang, P. L.; Wang, S. G.; Wang, W.; Wang, W. P.; Wang, X. F.; Wang, Y.; Wang, Y. D.; Wang, Y. F.; Wang, Y. Q.; Wang, Z.; Wang, Z. G.; Wang, Z. H.; Wang, Z. Y.; Wang, Z. Y.; Weber, T.; Wei, D. H.; Wei, J. B.; Weidenkaff, P.; Wen, S. P.; Wiedner, U.; Wolke, M.; Wu, L. H.; Wu, L. J.; Wu, Z.; Xia, L.; Xia, L. G.; Xia, Y.; Xiao, D.; Xiao, H.; Xiao, Z. J.; Xie, Y. G.; Xiu, Q. L.; Xu, G. F.; Xu, J. J.; Xu, L.; Xu, Q. J.; Xu, Q. N.; Xu, X. P.; Yan, L.; Yan, W. B.; Yan, W. C.; Yan, Y. H.; Yang, H. J.; Yang, H. X.; Yang, L.; Yang, Y. X.; Ye, M.; Ye, M. H.; Yin, J. H.; Yu, B. X.; Yu, C. X.; Yu, J. S.; Yuan, C. Z.; Yuan, W. L.; Yuan, Y.; Yuncu, A.; Zafar, A. A.; Zallo, A.; Zeng, Y.; Zeng, Z.; Zhang, B. X.; Zhang, B. Y.; Zhang, C.; Zhang, C. C.; Zhang, D. H.; Zhang, H. H.; Zhang, H. Y.; Zhang, J.; Zhang, J. J.; Zhang, J. L.; Zhang, J. Q.; Zhang, J. W.; Zhang, J. Y.; Zhang, J. Z.; Zhang, K.; Zhang, L.; Zhang, S. Q.; Zhang, X. Y.; Zhang, Y.; Zhang, Y. H.; Zhang, Y. N.; Zhang, Y. T.; Zhang, Yu; Zhang, Z. H.; Zhang, Z. P.; Zhang, Z. Y.; Zhao, G.; Zhao, J. W.; Zhao, J. Y.; Zhao, J. Z.; Zhao, Lei; Zhao, Ling; Zhao, M. G.; Zhao, Q.; Zhao, Q. W.; Zhao, S. J.; Zhao, T. C.; Zhao, Y. B.; Zhao, Z. G.; Zhemchugov, A.; Zheng, B.; Zheng, J. P.; Zheng, W. J.; Zheng, Y. H.; Zhong, B.; Zhou, L.; Zhou, X.; Zhou, X. K.; Zhou, X. R.; Zhou, X. Y.; Zhu, K.; Zhu, K. J.; Zhu, S.; Zhu, S. H.; Zhu, X. L.; Zhu, Y. C.; Zhu, Y. S.; Zhu, Z. A.; Zhuang, J.; Zotti, L.; Zou, B. S.; Zou, J. H.; Besiii Collaboration

    2016-06-01

    A search for radiative decays of the P -wave spin singlet charmonium resonance hc is performed based on 4.48 ×108 ψ' events collected with the BESIII detector operating at the BEPCII storage ring. Events of the reaction channels hc→γ η' and γ η are observed with a statistical significance of 8.4 σ and 4.0 σ , respectively, for the first time. The branching fractions of hc→γ η' and hc→γ η are measured to be B (hc→γ η')=(1.52 ±0.27 ±0.29 )×10-3 and B (hc→γ η )=(4.7 ±1.5 ±1.4 )×10-4, respectively, where the first errors are statistical and the second are systematic uncertainties.

  16. Direct hydrocarbon fuel cells

    Science.gov (United States)

    Barnett, Scott A.; Lai, Tammy; Liu, Jiang

    2010-05-04

    The direct electrochemical oxidation of hydrocarbons in solid oxide fuel cells, to generate greater power densities at lower temperatures without carbon deposition. The performance obtained is comparable to that of fuel cells used for hydrogen, and is achieved by using novel anode composites at low operating temperatures. Such solid oxide fuel cells, regardless of fuel source or operation, can be configured advantageously using the structural geometries of this invention.

  17. Hydrocarbon removal from bilgewater by a combination of air-stripping and photocatalysis

    Energy Technology Data Exchange (ETDEWEB)

    Cazoir, D., E-mail: david.cazoir@ircelyon.univ-lyon1.fr [University Lyon 1, Lyon, F-69626, France, CNRS, UMR5256, IRCELYON, Institut de Recherches sur la Catalyse et l' Environnement de Lyon, Villeurbanne, F-69626 (France); Fine, L.; Ferronato, C.; Chovelon, J.-M. [University Lyon 1, Lyon, F-69626, France, CNRS, UMR5256, IRCELYON, Institut de Recherches sur la Catalyse et l' Environnement de Lyon, Villeurbanne, F-69626 (France)

    2012-10-15

    Highlights: Black-Right-Pointing-Pointer Bilge water is an oily effluent that contaminates oceans and seas (MARPOL73/78). Black-Right-Pointing-Pointer Hydrocarbon removal was studied by photocatalysis and air-stripping, together used. Black-Right-Pointing-Pointer Both aqueous and gaseous phases were monitored by GC-MS during the process. Black-Right-Pointing-Pointer The combined process showed a better efficiency and a synergistic effect. Black-Right-Pointing-Pointer N-Alkanes (N{sub C} > 15) appeared as being the most refractory compounds. - Abstract: In order to prevent hydrocarbon discharge at sea from the bilge of ships, the International Maritime Organization (IMO) enacted the MARPOL 73/78 convention in which effluents are now limited to those with maximum oil content of 15 ppmv. Thus, photocatalysis and air-stripping were combined for the hydrocarbon removal from a real oily bilgewater sample and an original monitoring of both aqueous and gaseous phases was performed by GC/MS to better understand the process. Our results show that the hydrocarbon oil index [HC] can be reduced to its maximum permissible value of 15 ppmv (MARPOL) in only 8.5 h when photocatalysis and air-stripping are used together in a synergistic way, as against 17 h when photocatalysis is used alone. However, this air-assisted photocatalytic process emits a large quantity of volatile organic compounds (VOC) and, within the first four hours, ca. 10% of the hydrocarbon removal in the aqueous phase is actually just transferred into the gaseous one. Finally, we highlight that the n-alkanes with a number of carbon atoms higher than 15 (N{sub C} > 15) are those which most decrease the rate of [HC] removal.

  18. THERMOCHEMISTRY OF HYDROCARBON RADICALS

    Energy Technology Data Exchange (ETDEWEB)

    Kent M. Ervin, Principal Investigator

    2004-08-17

    Gas phase negative ion chemistry methods are employed to determine enthalpies of formation of hydrocarbon radicals that are important in combustion processes and to investigate the dynamics of ion-molecule reactions. Using guided ion beam tandem mass spectrometry, we measure collisional threshold energies of endoergic proton transfer and hydrogen atom transfer reactions of hydrocarbon molecules with negative reagent ions. The measured reaction threshold energies for proton transfer yield the relative gas phase acidities. In an alternative methodology, competitive collision-induced dissociation of proton-bound ion-molecule complexes provides accurate gas phase acidities relative to a reference acid. Combined with the electron affinity of the R {center_dot} radical, the gas phase acidity yields the RH bond dissociation energy of the corresponding neutral molecule, or equivalently the enthalpy of formation of the R{center_dot} organic radical, using equation: D(R-H) = {Delta}{sub acid}H(RH) + EA(R) - IE(H). The threshold energy for hydrogen abstraction from a hydrocarbon molecule yields its hydrogen atom affinity relative to the reagent anion, providing the RH bond dissociation energy directly. Electronic structure calculations are used to evaluate the possibility of potential energy barriers or dynamical constrictions along the reaction path, and as input for RRKM and phase space theory calculations. In newer experiments, we have measured the product velocity distributions to obtain additional information on the energetics and dynamics of the reactions.

  19. Land Cover Mapping in Southwestern China Using the HC-MMK Approach

    Directory of Open Access Journals (Sweden)

    Guangbin Lei

    2016-04-01

    Full Text Available Land cover mapping in mountainous areas is a notoriously challenging task due to the rugged terrain and high spatial heterogeneity of land surfaces as well as the frequent cloud contamination of satellite imagery. Taking Southwestern China (a typical mountainous region as an example, this paper established a new HC-MMK approach (Hierarchical Classification based on Multi-source and Multi-temporal data and geo-Knowledge, which was especially designed for land cover mapping in mountainous areas. This approach was taken in order to generate a 30 m-resolution land cover product in Southwestern China in 2010 (hereinafter referred to as CLC-SW2010. The multi-temporal native HJ (HuanJing, small satellite constellation for disaster and environmental monitoring CCD (Charge-Coupled Device images, Landsat TM (Thematic Mapper images and topographical data (including elevation, aspect, slope, etc. were taken as the main input data sources. Hierarchical classification tree construction and a five-step knowledge-based interactive quality control were the major components of this proposed approach. The CLC-SW2010 product contained six primary categories and 38 secondary categories, which covered about 2.33 million km2 (accounting for about a quarter of the land area of China. The accuracies of primary and secondary categories for CLC-SW2010 reached 95.09% and 87.14%, respectively, which were assessed independently by a third-party group. This product has so far been used to estimate the terrestrial carbon stocks and assess the quality of the ecological environments. The proposed HC-MMK approach could be used not only in mountainous areas, but also for plains, hills and other regions. Meanwhile, this study could also be used as a reference for other land cover mapping projects over large areas or even the entire globe.

  20. Millimeter-Wave Spectroscopy of Formyl Azide (HC(O)N_3)

    Science.gov (United States)

    Walters, Nicholas A.; Amberger, Brent K.; Esselman, Brian J.; Woods, R. Claude; McMahon, Robert J.

    2015-06-01

    Formyl azide (HC(O)N_3) is a highly unstable molecule (t1/2˜2 hours at room temperature as a gas) that has only recently been studied spectroscopically by UV, IR, Raman and NMR methods. We have synthesized formyl azide and obtained its absorption spectrum at room temperature over the range 250-360 GHz. As in the case of carbonyl diazide, two conformers are expected for HC(O)N_3, with the syn-isomer 2.8 kcal/mol lower in energy than the anti-isomer (CCSD(T)/ANO1). Calculations at the same level of theory and the same basis set predict the dipole moments for the syn-isomer (μ = 1.56 D) and anti-isomer (μ = 2.56 D). These calculations also indicate that b-type transitions should dominate the syn-isomer spectrum, while a-type transitions become more significant in the case of the anti-isomer. Despite the anti-isomer having a larger dipole moment, the syn-isomer still gives rise to all the dominant features of the spectrum. Thus far, five vibrational states (νb{9}, νb{12}, 2νb{9}, νb{9} + νb{12}, νb{11}) have been studied for the syn-isomer, with the highest energy state νb{11} = 582.6 wn. Searches for the spectra of the anti-isomer are ongoing. Banert, K. et al. Angew. Chem. Int. Ed. 2012, 51, 4718-4721 Zeng, X. et al. Angew. Chem. Int. Ed. 2013, 52, 3503-3506 Amberger, B.K. et al. J. Mol. Spectrosc. 259, (2014) 15-20

  1. ACCUMULATION AND IMMUNOLOCALIZATION OF Maize dwarf mosaic virus HC-Pro IN INFECTED MAIZE LEAVES%MDMV HC-PrO在玉米叶片中的积累及免疫定位

    Institute of Scientific and Technical Information of China (English)

    李向东; 范在丰; 李怀方; 裘维蕃

    2001-01-01

    本文以感病自交系Mo17、掖107和抗病自交系黄早四为材料,研究了玉米矮花叶病毒(MDMV)和MDMV辅助成份-蛋白酶(HC-Pro)在叶片中的积累动态和细胞内定位.结果表明,在接种后3 d,MDMV就在掖107和Mo17接种叶的上位叶积累到了相当高的程度,6 d后达到高峰;而MDMV在黄早四中的浓度一直低于在掖107和Mo17中的浓度.在接种掖107和Mo17 6 d后,MDMV HC-Pro在上位叶中的积累到达高峰,而在黄早四植株中MDMV HC-Pro直到第9 d才到最高,而且浓度一直低于感病自交系掖107和Mo17.麦二叉蚜从发病植株上获毒后的传毒效率变化与MDMV、MDMV HC-Pro在叶片中的积累动态一致.通过胶体金标记对MDMV HC-Pm进行免疫定位,发现在细胞质中、与质膜相联系的风轮状内含体、片层凝集状内含体、细胞质高密度物质和病毒粒子周围有金标记,说明在这些部位有MDMV HC-Pro的存在.

  2. Particulate hydroxy-PAH emissions from a residential wood log stove using different fuels and burning conditions

    Science.gov (United States)

    Avagyan, Rozanna; Nyström, Robin; Lindgren, Robert; Boman, Christoffer; Westerholm, Roger

    2016-09-01

    Hydroxylated polycyclic aromatic hydrocarbons are oxidation products of polycyclic aromatic hydrocarbons, but have not been studied as extensively as polycyclic aromatic hydrocarbons. Several studies have however shown that hydroxylated polycyclic aromatic hydrocarbons have toxic and carcinogenic properties. They have been detected in air samples in semi urban areas and combustion is assumed to be the primary source of those compounds. To better understand the formation and occurrence of particulate hydroxylated polycyclic aromatic hydrocarbons from residential wood log stove combustion, 9 hydroxylated polycyclic aromatic hydrocarbons and 2 hydroxy biphenyls were quantified in particles generated from four different types of wood logs (birch, spruce, pine, aspen) and two different combustion conditions (nominal and high burn rate). A previously developed method utilizing liquid chromatography - photo ionization tandem mass spectrometry and pressurized liquid extraction was used. Polycyclic aromatic hydrocarbons were analyzed along with hydroxylated polycyclic aromatic hydrocarbons. The hydroxylated polycyclic aromatic hydrocarbon emissions varied significantly across different wood types and burning conditions; the highest emissions for nominal burn rate were from spruce and for high burn rate from pine burning. Emissions from nominal burn rate corresponded on average to 15% of the emissions from high burn rate, with average emissions of 218 μg/MJfuel and 32.5 μg/MJfuel for high burn rate and nominal burn rate, respectively. Emissions of the measured hydroxylated polycyclic aromatic hydrocarbons corresponded on average to 28% of polycyclic aromatic hydrocarbons emissions. This study shows that wood combustion is a large emission source of hydroxylated polycyclic aromatic hydrocarbons and that not only combustion conditions, but also wood type influences the emissions of hydroxylated polycyclic aromatic hydrocarbons and polycyclic aromatic hydrocarbons. There are

  3. Experimental Study on the Characteristics Polycyclic Aromatic Hydrocarbon Emissions of Diesel Engine Burnt by Different Fuels%不同燃料柴油机多环芳烃排放特征的试验研究

    Institute of Scientific and Technical Information of China (English)

    王忠; 安玉光; 许广举; 王小哲

    2011-01-01

    The polycyclic aromatic hydrocarbons(PAHs) were measured by glass fiber filter and XAD-2 collector,ultrasonic extraction,soxhlet extraction and GC-MS analysis equipment.The exhaust emission of the DI single cylinder diesel engine fueled with pure diesel,biodiesel and biodiesel blends of 50%(B50) were measured.The results indicate that the particle-phase PAHs emissions of diesel engine decrease with the increasing of load.The gas-phase PAHs emissions of diesel engine decrease with the increasing of load in the beginning and it turns to going up with further increasing of load.The particle-phase and gas-phase PAHs emissions of biodiesel decrease and mean concentration are lower than that of diesel.The total PAHs emission concentration of biodisesl is 41.1-70.1μg/m^3.Total PAHs mean concentration emissions of biodiesel is decreased 33.3% than that of diesel.The mass proportion of three-ring PAHs emissions of those 3 kinds tested fuels is about 44% in the total PAHs.Biodiesel can increase the proportion of three-ring PAHs.Toxic equivalence of PAHs emissions of biodiesel are greatly lower than that of diesel.It is less harmful to human than diesel fuel.%在一台直喷式柴油机上,采用玻璃纤维滤纸及XAD-2吸附管采集、超声和索氏提取、气质联用分析等技术,测量了燃用柴油、生物柴油及其调合油B50排气中的多环芳烃类污染物(PAHs).研究表明,柴油机颗粒相PAHs排放随着负荷的增大呈现降低的趋势,气相PAHs排放随着负荷呈现先降低后升高的趋势.与柴油相比,生物柴油的颗粒相和气相PAHs排放有所降低,其平均排放浓度也均低于柴油.生物柴油排气中总PAHs排放浓度为41.1~70.1μg/m^3,总PAHs的平均排放浓度与柴油相比下降了33.3%.3种不同燃料的三环P

  4. Deuterated polycyclic aromatic hydrocarbons: Revisited

    CERN Document Server

    Doney, Kirstin D; Mori, Tamami; Onaka, Takashi; Tielens, A G G M

    2016-01-01

    The amount of deuterium locked up in polycyclic aromatic hydrocarbons (PAHs) has to date been an uncertain value. We present a near-infrared (NIR) spectroscopic survey of HII regions in the Milky Way, Large Magellanic Cloud (LMC), and Small Magellanic Cloud (SMC) obtained with AKARI, which aims to search for features indicative of deuterated PAHs (PAD or Dn-PAH) to better constrain the D/H ratio of PAHs. Fifty-three HII regions were observed in the NIR (2.5-5 {\\mu}m), using the Infrared Camera (IRC) on board the AKARI satellite. Through comparison of the observed spectra with a theoretical model of deuterated PAH vibrational modes, the aromatic and (a)symmetric aliphatic C-D stretch modes were identified. We see emission features between 4.4-4.8 {\\mu}m, which could be unambiguously attributed to deuterated PAHs in only six of the observed sources, all of which are located in the Milky Way. In all cases, the aromatic C-D stretching feature is weaker than the aliphatic C-D stretching feature, and, in the case o...

  5. The exohedral Diels-Alder reactivity of the titanium carbide endohedral metallofullerene Ti2C2@D(3h)-C78: comparison with D(3h)-C78 and M3N@D(3h)-C78 (M=Sc and Y) reactivity.

    Science.gov (United States)

    Garcia-Borràs, Marc; Osuna, Sílvia; Luis, Josep M; Swart, Marcel; Solà, Miquel

    2012-06-04

    The chemical functionalization of endohedral (metallo)fullerenes has become a main focus of research in the last few years. It has been found that the reactivity of endohedral (metallo)fullerenes may be quite different from that of the empty fullerenes. Encapsulated species have an enormous influence on the thermodynamics, kinetics, and regiochemistry of the exohedral addition reactions undergone by these species. A detailed understanding of the changes in chemical reactivity due to incarceration of atoms or clusters of atoms is essential to assist the synthesis of new functionalized endohedral fullerenes with specific properties. Herein, we report the study of the Diels-Alder cycloaddition between 1,3-butadiene and all nonequivalent bonds of the Ti(2)C(2)@D(3h)-C(78) metallic carbide endohedral metallofullerene (EMF) at the BP86/TZP//BP86/DZP level of theory. The results obtained are compared with those found by some of us at the same level of theory for the D(3h)-C(78) free cage and the M(3)N@D(3h)-C(78) (M=Sc and Y) metallic nitride EMFs. It is found that the free cage is more reactive than the Ti(2)C(2)@D(3h)-C(78) EMF and this, in turn, has a higher reactivity than M(3)N@D(3h)-C(78). The results indicate that, for Ti(2)C(2)@D(3h)-C(78), the corannulene-type [5,6] bonds c and f, and the type B [6,6] bond 3 are those thermodynamically and kinetically preferred. In contrast, the D(3h)-C(78) free cage has a preference for addition to the [6,6] 1 and 6 bonds and the [5,6] b bond, whereas M(3)N@D(3h)-C(78) favors additions to the [6,6] 6 (M=Sc) and [5,6] d (M=Y) bonds. The reasons for the regioselectivity found in Ti(2)C(2)@D(3h)-C(78) are discussed.

  6. [The primary role of central region of HC-pro of potato Y potyvirus in synergism of plant viruses].

    Science.gov (United States)

    Lu, R F; Li, W M; Wang, H Y; Guo, M; Peng, X X

    2001-05-01

    Five deleted mutants of HC-Pro gene of Chinese isolate of potato Y potyvirus (PVY-C) were obtained by PCR mutation, and their plant expression vectors were constructed. They were transformed into tobacco K326 (Nicotina tabacum cv. K326) mediated by Agrobacterium. PCR and Southern blot analysis revealed that PVY-C HC-Pro gene and its deleted mutants were integrated into tobacco genome, and Western blot analysis showed that they were all expressed in transgenic tobacco plants. Furthermore, infection test demonstrated that the central region of PVY-C HC-Pro can mediate synergism of PVY-C/cucumber mosaic cucumovirus (CMV) and PVY-C/potato X potexvirus (PVX), identifying that it is functional domain in synergism.

  7. Evolution of pollutants emissions by transports in france from 1970 to 2010; Evolution des emissions de polluants par les transports en France de 1970 a 2010

    Energy Technology Data Exchange (ETDEWEB)

    Joumard, R.; Lambert, J.

    1996-07-01

    Fuel consumption and CO, CO{sub 2}, HC, NOx, particulates and PAH amounts released by all transport modes from 1970 to 2010 are calculated. A thorough analysis, using parc and pollen softwares, was performed for road traffic. Three scenarios of transport development from 1989 are simulated. Results show that there will not be any problem with CO and HC emissions for the following 20 years, but emissions of nitrogen oxides and carbon dioxide will be significantly increased. Motorcycles and air transport are significantly polluting too, while duty vehicles, specifically diesel-engined cars, are the main polluting mode. Average unit emissions are analysed according to road type and vehicle type. (author)

  8. In vivo study of the HC-TN strain of hepatitis C virus recovered from a patient with fulminant hepatitis: RNA transcripts of a molecular clone (pHC-TN) are infectious in chimpanzees but not in Huh7.5 cells

    DEFF Research Database (Denmark)

    Sakai, Akito; Takikawa, Shingo; Thimme, Robert

    2007-01-01

    disease severity, host immune response, viral evolution, and outcome. A second chimpanzee (CH1581) was infected from CH1422 plasma, and a third chimpanzee (CH1579) was infected from RNA transcripts of a consensus cDNA of HC-TN (pHC-TN). RNA transcripts of pHC-TN did not replicate in Huh7.5 cells, which...

  9. Arsenic-containing hydrocarbons are toxic in the in vivo model Drosophila melanogaster.

    Science.gov (United States)

    Meyer, S; Schulz, J; Jeibmann, A; Taleshi, M S; Ebert, F; Francesconi, K A; Schwerdtle, T

    2014-11-01

    Arsenic-containing hydrocarbons (AsHC) constitute one group of arsenolipids that have been identified in seafood. In this first in vivo toxicity study for AsHCs, we show that AsHCs exert toxic effects in Drosophila melanogaster in a concentration range similar to that of arsenite. In contrast to arsenite, however, AsHCs cause developmental toxicity in the late developmental stages of Drosophila melanogaster. This work illustrates the need for a full characterisation of the toxicity of AsHCs in experimental animals to finally assess the risk to human health related to the presence of arsenolipids in seafood.

  10. Decomposition mechanisms and non-isothermal kinetics of LiHC_2O_4·H_2O

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    The thermal decomposition process of LiHC2O4·H2O from 30 to 600 ℃ was investigated by the thermogravimetric and differential scanning calorimetry (TG-DSC). The phases decomposited at different temperature were characterized by X-ray diffraction (XRD), which indicated the decompositions at 150, 170, and 420℃, relating to LiHC2O4, Li2C2O4, Li2C2O4, and Li2CO3, respectively. Reaction mechanisms in the whole sintering process were determined, and the model fitting kinetic approaches were applied to data for non...

  11. Ultraviolet Studies of Jupiter's Hydrocarbons and Aerosols from Galileo

    Science.gov (United States)

    Gladstone, G. Randall

    2001-01-01

    This is the final report for this project. The purpose of this project was to support PI Wayne Pryor's effort to reduce and analyze Galileo UVS (Ultraviolet Spectrometer) data under the JSDAP program. The spectral observations made by the Galileo UVS were to be analyzed to determine mixing ratios for important hydrocarbon species (and aerosols) in Jupiter's stratosphere as a function of location on Jupiter. Much of this work is still ongoing. To date, we have concentrated on analyzing the variability of the auroral emissions rather than the absorption signatures of hydrocarbons, although we have done some work in this area with related HST-STIS data.

  12. Effect of hydrocarbons and nitrogen oxides on ozone formation in smog chambers exposed to solar irradiance of Mexico City

    Energy Technology Data Exchange (ETDEWEB)

    Sandoval F, J; Marroquin de la R, O; Jaimes L, J. L; Zuniga L, V. A; Gonzalez O, E; Guzman Lopez-Figueroa, F [Instituto Mexicano del Petroleo, Mexico, D.F. (Mexico)

    2001-01-01

    Outdoor smog chambers experiments were performed on air to determine the answer of maximum ozone levels, to changes in the initial hydrocarbons, HC, and nitrogen oxide NO{sub x}. These captive-air experiments under natural irradiation were carried out. Typically, eight chambers were filled with Mexico city air in the morning. In some of those chambers, the initial HC and/or Nox concentrations were varied by {+-}25% to {+-}50% by adding various combinations of a mixture of HC, clean air, or NO{sub x} (perturbed chambers). The O{sub 3} and NO{sub x} concentration in each chamber was monitored throughout the day to determine O{sub 3} (max). The initial HC and NO{sub x} concentration effects were determined by comparing the maximum ozone concentrations measured in the perturbed and unperturbed chambers. Ozone isopleths were constructed from the empirical model obtained of measurements of the eight chambers and plotted in a graph whose axe were the initial HC and NO{sub x} values. For the average initial conditions that were measured in Mexico City, it was found that the most efficient strategy to reduce the maximum concentration of O{sub 3} is the one that reduces NO{sub x}. [Spanish] Se realizaron experimentos de camaras de esmog con el aire de la ciudad de Mexico para determinar las respuestas de los niveles maximos de ozono a los cambios en las concentraciones iniciales de hidrocarburos, HC y oxido de nitrogeno, NO{sub x}. Por lo general, se llenaron 8 bolsas con aire matutino de la Ciudad de Mexico. En algunas camaras, las concentraciones iniciales fueron cambiadas de 25% a 50%, anadiendo varias concentraciones de una mezcla de HC, aire limpio y/o NO{sub x}. La concentracion de O{sub 3} y NO{sub x}, en cada camara, fueron monitoreadas a lo largo del dia para determinar el maximo de O{sub 3}. El efecto de los HC y el NO{sub x} fue determinado por comparacion del maximo de ozono formado en las camaras, que fueron perturbadas por adicion o reduccion de HC y/o Nox

  13. Study on Conversion of Municipal Plastic Wastes into Liquid Fuel Compounds, Analysis of Crdi Engine Performance and Emission Characteristics

    Science.gov (United States)

    Divakar Shetty, A. S.; Kumar, R. Ravi; Kumarappa, S.; Antony, A. J.

    2016-09-01

    The rate of economic evolution is untenable unless we save or stops misusing the fossil fuels like coal, crude oil or fossil fuels. So we are in need of start count on the alternate or renewable energy sources. In this experimental analysis an attempt has been made to investigate the conversion of municipal plastic wastes like milk covers and water bottles are selected as feed stocks to get oil using pyrolysis method, the performance analysis on CRDI diesel engine and to assess emission characteristics like HC, CO, NOX and smoke by using blends of Diesel-Plastic liquid fuels. The plastic fuel is done with the pH test using pH meter after the purification process and brought to the normal by adding KOH and NaOH. Blends of 0 to 100% plastic liquid fuel-diesel mixture have been tested for performance and emission aspect as well. The experimental results shows the efficiently convert weight of municipal waste plastics into 65% of useful liquid hydrocarbon fuels without emitting much pollutants.

  14. One century of air deposition of hydrocarbons recorded in travertine in North Tibetan Plateau, China: Sources and evolution.

    Science.gov (United States)

    Yuan, Guo-Li; Wu, Ming-Zhe; Sun, Yong; Li, Jun; Li, Jing-Chao; Wang, Gen-Hou

    2016-08-01

    The characteristic distribution patterns of hydrocarbons have been used for fingerprinting to identify their sources. The historical air depositions of hydrocarbons recorded in natural media help to understand the evolution of the air environment. Travertine is a natural acceptor of air deposition that settles on the ground layer by layer. To reconstruct the historical air environment of hydrocarbons in the North Tibetan Plateau (NTP), a unique background region, twenty-seven travertine samples were collected systematically from a travertine column according to its precipitated year. For each sample, the precipitated year was dated while n-alkanes and polycyclic aromatic hydrocarbons (PAHs) were determined. Based on source identification, the air environment of hydrocarbons in the past century was studied for the region of NTP. Before World War II, the anthropogenic sources of hydrocarbons showed little influence on the air environment. During World War II and China's War of Liberation, hydrocarbons increased significantly, mainly from the use of fossil fuels. Between 1954 and 1963, hydrocarbons in the air decreased significantly because the sources of petroleum combustion decreased. From the mid-1960s through the end of the 1990s, air hydrocarbons, which mainly originated from biomass burning, increased gradually because agriculture and animal husbandry were developing steadily in Tibet and China. From the late 1990s, hydrocarbons in the atmosphere increased rapidly due to the rapid increase of tourism activities, which might increase hydrocarbon emissions from traffic. The reconstruction of the historical air hydrocarbons in NTP clearly reflects the evolution of the region and global development.

  15. A novel inclusion complex (β-CD/ABP-dHC-cecropin A) with antibiotic propertiess for use as an anti-Agrobacterium additive in transgenic poplar rooting medium.

    Science.gov (United States)

    Zhang, Jiaxin; Li, Jianfeng; Movahedi, Ali; Sang, Ming; Xu, Chen; Xu, Junjie; Wei, Zhiheng; Yin, Tongming; Zhuge, Qiang

    2015-12-01

    The increasing resistance of bacteria and fungi to currently available antibiotics is a major concern worldwide, leading to enormous effort to develop novel antibiotics with new modes of action.We recently reported that ABP-dHC-cecropin A exhibited strong antibacterial and antifungal activity, making it a candidate antibiotic substitute. In this study, β-cyclodextrin (β-CD) combined with ABP-dHC-cecropin A enhanced the physical and chemical properties of ABP-dHC-cecropin A but did not significantly decrease its antibacterial activity. Thus, β-CD/ABP-dHC-cecropin A should be considered a novel antibacterial drug. We used β-CD/ABP-dHC-cecropin A as an anti-Agrobacterium compound to supplementtransgenic poplar medium. Sideeffects of the inclusion complex had little impact on plantgrowth. Thus, β-CD/ABP-dHC-cecropin A may be used as traditional antibiotics forpoplar transplantation with greater antibbacterial effects.

  16. Interaction of the Chlamydia trachomatis histone H1-like protein (Hc1) with DNA and RNA causes repression of transcription and translation in vitro

    DEFF Research Database (Denmark)

    Pedersen, Lotte Bang; Birkelund, S; Christiansen, G

    1994-01-01

    The 18 kDa histone H1-like protein from Chlamydia trachomatis (Hc1) is a DNA-binding protein thought to be involved in condensation of the chlamydial chromosome during late stages in the chlamydial life cycle. Expression of Hc1 in Escherichia coli results in an overall relaxation of DNA and sever......The 18 kDa histone H1-like protein from Chlamydia trachomatis (Hc1) is a DNA-binding protein thought to be involved in condensation of the chlamydial chromosome during late stages in the chlamydial life cycle. Expression of Hc1 in Escherichia coli results in an overall relaxation of DNA...... and severely affects DNA, RNA and protein synthesis. We have analysed the interaction of Hc1 with single-stranded DNA and RNA by Southwestern and Northwestern blotting. Furthermore, we show that purified, recombinant Hc1 dramatically affects transcription and translation in vitro at physiologically relevant...

  17. 捻转血矛线虫Hc38基因DNA疫苗对绵羊免疫保护性效果评价%Protective effects of Hc38 DNA vaccines against Haemonchus contortus in sheep

    Institute of Scientific and Technical Information of China (English)

    郑金海; 段正秀; 赵军明; 薄新文; 钟发刚; 张慧

    2009-01-01

    To study protective effects of Hc38 DNA vaccines against Haemonchus contortus in sheep, we constructed DNA vaccines containing conserved Hc38 protein domain. The Hc38 gene was inserted into pcDNA3.1 and administered to mice. Transcriptions of the vaccines were confirmed by RT-PCR in mouse muscles. Sheep were immunized with DNA vaccine and antibody (IgG) production was analyzed by western blot and ELISA. After 2 weeks, all sheep were challenged by 10000 H. Contortus L3 strain. The results showed that EPG (eggs per gram feces) and worm burdens in immunized sheep reduced by 66.6 % and 33.1%, compared to the control group. Vaccination by intravenous injection induced highest antibody level and resulted in lowest EPG and worm burdens in sheep.%为了研究基因疫苗对绵羊的免疫保护效果,本研究构建了捻转血矛线虫(H.contortus)Hc38基因DNA疫苗.将H.contortus Hc38基因保守结构域克隆到真核表达载体pcDNA3.1中,免疫鼠8d后用RT-PCR检测到该疫苗在鼠肌肉组织中进行了转录.将纯化的DNA疫苗免疫绵羊后,用western blot和ELISA方法检测疫苗在绵羊体内的翻译和诱导IgG的产生.二免后2周用10 000条H.contortus第3期幼虫攻击实验动物,检测绵羊粪便虫卵排出、成虫数量等免疫保护性指标.该H.contortus Hc38 DNA疫苗与对照组比较,免疫组绵羊排出虫卵减少66.6%、成虫减少33.1%.特别值得注意的是免疫组的静脉注射方式产生抗体最高,相应羊的虫卵数和成虫数低.本实验证明Hc38基因DNA疫苗对绵羊虫卵及成虫发育具有明显的抑制作用.

  18. Application of automobile emission control technology to light piston aircraft engines

    Science.gov (United States)

    Tripp, D.; Kittredge, G.

    1976-01-01

    The possibility was evaluated for achieving the EPA Standards for HC and CO emissions through the use of air-fuel ratio enleanment at selected power modes combined with improved air-fuel mixture preparation, and in some cases improved cooling. Air injection was also an effective approach for the reduction of HC and CO, particularly when combined with exhaust heat conservation techniques such as exhaust port liners.

  19. PM₂.₅-bound polycyclic aromatic hydrocarbons in an area of Rio de Janeiro, Brazil impacted by emissions of light-duty vehicles fueled by ethanol-blended gasoline.

    Science.gov (United States)

    Oliveira, Rafael Lopes; Loyola, Josiane; Minho, Alan Silva; Quiterio, Simone Lorena; de Almeida Azevedo, Débora; Arbilla, Graciela

    2014-12-01

    The aim of this study was to characterize the PM2.5-bound polycyclic aromatic hydrocarbon (PAH) concentrations and their diagnostic ratios in an area impacted by light-duty vehicles fueled by neat ethanol and ethanol-blended gasoline. Samples were collected using a high-volume sampler, extracted, and analyzed for all 16 EPA-priority PAHs using gas chromatography/mass spectrometry (GC/MS) following the EPA 3550B Method. The most abundant PAHs were benzo[g,h,i]perylene, benzo[b]fluoranthene, benzo[a]pyrene and indeno[1,2,3-c,d]pyrene. The total mean concentration was 3.80 ± 2.88 ng m(-3), and the contribution of carcinogenic species was 58 ± 16 % of the total PAHs. The cumulative health hazard from the PAH mixture was determined, and the carcinogenic equivalents and mutagenic equivalents were 0.80 ± 0.82 and 1.17 ± 1.04 ng m(-3), respectively. Diagnostic ratios and normalized ratios were calculated for the individual samples.

  20. High-level SUMO-mediated fusion expression of ABP-dHC-cecropin A from multiple joined genes in Escherichia coli.

    Science.gov (United States)

    Zhang, Jiaxin; Movahedi, Ali; Wei, Zhiheng; Sang, Ming; Wu, Xiaolong; Wang, Mengyang; Wei, Hui; Pan, Huixin; Yin, Tongming; Zhuge, Qiang

    2016-09-15

    The antimicrobial peptide ABP-dHC-cecropin A is a small cationic peptide with potent activity against a wide range of bacterial species. Evidence of antifungal activity has also been suggested; however, evaluation of this peptide has been limited due to the low expression of cecropin proteins in Escherichia coli. To improve the expression level of ABP-dHC-cecropin A in E. coli, tandem repeats of the ABP-dHC-cecropin A gene were constructed and expressed as fusion proteins (SUMO-nABP-dHC-cecropin, n = 1, 2, 3, 4) via pSUMO-nABP-dHC-cecropin A vectors (n = 1, 2, 3, 4). Comparison of the expression levels of soluble SUMO-nABP-dHC-cecropin A fusion proteins (n = 1, 2, 3, 4) suggested that BL21 (DE3)/pSUMO-3ABP-dHC-cecropin A is an ideal recombinant strain for ABP-dHC-cecropin A production. Under the selected conditions of cultivation and isopropylthiogalactoside (IPTG) induction, the expression level of ABP-dHC-cecropin A was as high as 65 mg/L, with ∼21.3% of the fusion protein in soluble form. By large-scale fermentation, protein production reached nearly 300 mg/L, which is the highest yield of ABP-dHC-cecropin A reported to date. In antibacterial experiments, the efficacy was approximately the same as that of synthetic ABP-dHC-cecropin A. This method provides a novel and effective means of producing large amounts of ABP-dHC-cecropin A.

  1. Federal Air Pollutant Emission Regulations and Preliminary Estimates of Potential-to-Emit from Biorefineries, Pathway #2: Conversion of Lignocellulosic Biomass to Hydrocarbon Fuels: Fast Pyrolysis and Hydrotreating Bio-oil Pathway

    Energy Technology Data Exchange (ETDEWEB)

    Bhatt, Arpit [National Renewable Energy Lab. (NREL), Golden, CO (United States). Strategic Energy Analysis Center. Technology Systems and Sustainability Analysis Group; Zhang, Yimin [National Renewable Energy Lab. (NREL), Golden, CO (United States). Strategic Energy Analysis Center. Technology Systems and Sustainability Analysis Group; Heath, Garvin [National Renewable Energy Lab. (NREL), Golden, CO (United States). Strategic Energy Analysis Center. Technology Systems and Sustainability Analysis Group; Thomas, Mae [Eastern Research Group, Research Triangle Park, NC (United States); Renzaglia, Jason [Eastern Research Group, Research Triangle Park, NC (United States)

    2017-01-01

    Biorefineries are subject to environmental laws, including complex air quality regulations that aim to protect and improve the quality of the air. These regulations govern the amount of certain types of air pollutants that can be emitted from different types of emission sources. To determine which federal air emission regulations potentially apply to the fast pyrolysis biorefinery, we first identified the types of regulated air pollutants emitted to the ambient environment by the biorefinery or from specific equipment. Once the regulated air pollutants are identified, we review the applicability criteria of each federal air regulation to determine whether the fast pyrolysis biorefinery or specific equipment is subject to it. We then estimate the potential-to-emit of pollutants likely to be emitted from the fast pyrolysis biorefinery to understand the air permitting requirements.

  2. Method to monitor HC-SCR catalyst NOx reduction performance for lean exhaust applications

    Science.gov (United States)

    Viola, Michael B.; Schmieg, Steven J.; Sloane, Thompson M.; Hilden, David L.; Mulawa, Patricia A.; Lee, Jong H.; Cheng, Shi-Wai S.

    2012-05-29

    A method for initiating a regeneration mode in selective catalytic reduction device utilizing hydrocarbons as a reductant includes monitoring a temperature within the aftertreatment system, monitoring a fuel dosing rate to the selective catalytic reduction device, monitoring an initial conversion efficiency, selecting a determined equation to estimate changes in a conversion efficiency of the selective catalytic reduction device based upon the monitored temperature and the monitored fuel dosing rate, estimating changes in the conversion efficiency based upon the determined equation and the initial conversion efficiency, and initiating a regeneration mode for the selective catalytic reduction device based upon the estimated changes in conversion efficiency.

  3. Hydrocarbon conversion catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Hoek, A.; Huizinga, T.; Maxwell, I.E.

    1989-08-15

    This patent describes a process for hydrocracking hydrocarbon oils into products of lower average molecular weight and lower average boiling point. It comprises contacting a hydrocarbon oil at a temperature between 250{sup 0}C and 500{sup 0}C and a pressure up to 300 bar in the presence of hydrogen with a catalyst consisting essentially of a Y zeolite modified to have a unit cell size below 24.35A, a water absorption capacity (at 25{sup 0}C and a rho/rho/sub o/ value of 0.2) of at least 8% by weight of the zeolite and a pore volume of at least 0.25 ml/g wherein between 10% and 60% of the total pore volume is made up of pores having a diameter of at least 8 nm; an alumina binder and at least one hydrogenation component selected from the group consisting of a Group VI metal, a Group VIII metal and mixtures thereof.

  4. HC StratoMineR: A Web-Based Tool for the Rapid Analysis of High-Content Datasets.

    Science.gov (United States)

    Omta, Wienand A; van Heesbeen, Roy G; Pagliero, Romina J; van der Velden, Lieke M; Lelieveld, Daphne; Nellen, Mehdi; Kramer, Maik; Yeong, Marley; Saeidi, Amir M; Medema, Rene H; Spruit, Marco; Brinkkemper, Sjaak; Klumperman, Judith; Egan, David A

    2016-10-01

    High-content screening (HCS) can generate large multidimensional datasets and when aligned with the appropriate data mining tools, it can yield valuable insights into the mechanism of action of bioactive molecules. However, easy-to-use data mining tools are not widely available, with the result that these datasets are frequently underutilized. Here, we present HC StratoMineR, a web-based tool for high-content data analysis. It is a decision-supportive platform that guides even non-expert users through a high-content data analysis workflow. HC StratoMineR is built by using My Structured Query Language for storage and querying, PHP: Hypertext Preprocessor as the main programming language, and jQuery for additional user interface functionality. R is used for statistical calculations, logic and data visualizations. Furthermore, C++ and graphical processor unit power is diffusely embedded in R by using the rcpp and rpud libraries for operations that are computationally highly intensive. We show that we can use HC StratoMineR for the analysis of multivariate data from a high-content siRNA knock-down screen and a small-molecule screen. It can be used to rapidly filter out undesirable data; to select relevant data; and to perform quality control, data reduction, data exploration, morphological hit picking, and data clustering. Our results demonstrate that HC StratoMineR can be used to functionally categorize HCS hits and, thus, provide valuable information for hit prioritization.

  5. Statistical analysis of the V-tool bending process parameters in the bending of HC260Y steel

    Directory of Open Access Journals (Sweden)

    J. Cumin

    2016-04-01

    Full Text Available This paper presents statistical analysis of the parameters in the V-tool bending process of the HC260Y steel. Assessment of the mathematical model and analysis of variance (ANOVA were performed within the design of experiments. The hydraulic testing machine Amsler and the developed V-tool were used in the experiments.

  6. HC-Pro protein of sugar cane mosaic virus interacts specifically with maize ferredoxin-5 in vitro and in planta.

    Science.gov (United States)

    Cheng, Yu-Qin; Liu, Zhong-Mei; Xu, Jian; Zhou, Tao; Wang, Meng; Chen, Yu-Ting; Li, Huai-Fang; Fan, Zai-Feng

    2008-08-01

    Symptom development of a plant viral disease is a result of molecular interactions between the virus and its host plant; thus, the elucidation of specific interactions is a prerequisite to reveal the mechanism of viral pathogenesis. Here, we show that the chloroplast precursor of ferredoxin-5 (Fd V) from maize (Zea mays) interacts with the multifunctional HC-Pro protein of sugar cane mosaic virus (SCMV) in yeast, Nicotiana benthamiana cells and maize protoplasts. Our results demonstrate that the transit peptide rather than the mature protein of Fd V precursor could interact with both N-terminal (residues 1-100) and C-terminal (residues 301-460) fragments, but not the middle part (residues 101-300), of HC-Pro. In addition, SCMV HC-Pro interacted only with Fd V, and not with the other two photosynthetic ferredoxin isoproteins (Fd I and Fd II) from maize plants. SCMV infection significantly downregulated the level of Fd V mRNA in maize plants; however, no obvious changes were observed in levels of Fd I and Fd II mRNA. These results suggest that SCMV HC-Pro interacts specifically with maize Fd V and that this interaction may disturb the post-translational import of Fd V into maize bundle-sheath cell chloroplasts, which could lead to the perturbation of chloroplast structure and function.

  7. Synthetic analysis of Tc and Hc2 of NbTi/Ti multilayers based on improved proximity effect theory

    Science.gov (United States)

    Obi, Y.; Ikebe, M.; Takanaka, K.; Fujimori, H.

    1994-12-01

    Tc and Hc2 of NbTi/Ti multilayers have been calculated based on an improved approximation for the proximity effect. Analysis reveals that the agreement between the calculation and the experiment is satisfactory except for some inevitable scatters of the sample quality.

  8. CSER 00-008 use of PFP Glovebox HC-18BS for Storage and Transport of Fissionable Material

    Energy Technology Data Exchange (ETDEWEB)

    ERICKSON, D.G.

    2000-06-01

    This CSER addresses the feasibility of increasing the allowed number of open containers and permitting the transfer and storage of fissionable material in Glovebox HC-18BS without regard to form or density (metal, oxide having an H/X {le} 20, material having unrestricted moderation and plutonium hydroxide having a plutonium density of 0.2 g/cm{sup 3}).

  9. The 18-kilodalton Chlamydia trachomatis histone H1-like protein (Hc1) contains a potential N-terminal dimerization site and a C-terminal nucleic acid-binding domain

    DEFF Research Database (Denmark)

    Pedersen, LB; Birkelund, Svend; Holm, A

    1996-01-01

    , in part, be due to Hc1-mediated alterations of DNA topology. To locate putative functional domains within Hc1, polypeptides Hc1(2-57) and Hc1(53-125), corresponding to the N- and C-terminal parts of Hc1, respectively, were generated. By chemical cross-linking with ethylene glycol-bis (succinic acid N...... retardation assays, Hc1(53-125) was shown to contain a domain capable of binding both DNA and RNA. Under the same conditions, Hc1(2-57) had no nucleic acid-binding activity. Electron microscopy of Hc1-DNA and Hc1(53-125)-DNA complexes revealed differences suggesting that the N-terminal part of Hc1 may affect...

  10. The 18-kilodalton Chlamydia trachomatis histone H1-like protein (Hc1) contains a potential N-terminal dimerization site and a C-terminal nucleic acid-binding domain

    DEFF Research Database (Denmark)

    Pedersen, LB; Birkelund, Svend; Holm, A

    1996-01-01

    , in part, be due to Hc1-mediated alterations of DNA topology. To locate putative functional domains within Hc1, polypeptides Hc1(2-57) and Hc1(53-125), corresponding to the N- and C-terminal parts of Hc1, respectively, were generated. By chemical cross-linking with ethylene glycol-bis (succinic acid N...... retardation assays, Hc1(53-125) was shown to contain a domain capable of binding both DNA and RNA. Under the same conditions, Hc1(2-57) had no nucleic acid-binding activity. Electron microscopy of Hc1-DNA and Hc1(53-125)-DNA complexes revealed differences suggesting that the N-terminal part of Hc1 may affect...

  11. Towards Carbon-Neutral CO2 Conversion to Hydrocarbons.

    Science.gov (United States)

    Mattia, Davide; Jones, Matthew D; O'Byrne, Justin P; Griffiths, Owen G; Owen, Rhodri E; Sackville, Emma; McManus, Marcelle; Plucinski, Pawel

    2015-12-07

    With fossil fuels still predicted to contribute close to 80 % of the primary energy consumption by 2040, methods to limit further CO2 emissions in the atmosphere are urgently needed to avoid the catastrophic scenarios associated with global warming. In parallel with improvements in energy efficiency and CO2 storage, the conversion of CO2 has emerged as a complementary route with significant potential. In this work we present the direct thermo-catalytic conversion of CO2 to hydrocarbons using a novel iron nanoparticle-carbon nanotube (Fe@CNT) catalyst. We adopted a holistic and systematic approach to CO2 conversion by integrating process optimization-identifying reaction conditions to maximize conversion and selectivity towards long chain hydrocarbons and/or short olefins-with catalyst optimization through the addition of promoters. The result is the production of valuable hydrocarbons in a manner that can approach carbon neutrality under realistic industrial process conditions.

  12. The Exclusive Decay of Upsilon into $h_c$, the $X(3940)$ and $X(4160)$

    CERN Document Server

    Zhu, Ruilin

    2015-01-01

    In this paper, we study double charmonia production in Upsilon peaks, especially, a S-wave charmonium $\\eta_c$ and a P-wave charmonium $h_c(^1P_1)$, or a S-wave charmonium $J/\\psi$ and the $X(3940)$ and $X(4160)$ within the nonrelativistic QCD (NRQCD) approach which is a powerful tool to realize the factorization of double charmonia production in Bottomonium peaks. The $J^{PC}=1^{--}$ state $\\Upsilon(nS)$ can provide an ideal laboratory for studying the properties of double-heavy quarkonium, and also well-separate the nonperturbative information due to its large heavy quark mass scale. Explanation of the $X(3940)$ and $X(4160)$ as the $3 ^1S_0$ and $4 ^1S_0$ states respectively are compatible with the observed upper limits for the branching fractions of $\\Upsilon(1S,2S)\\to J/\\psi+X$ where $X=X(3940)$, $X(4160)$ by the Belle Collaboration. The branching fractions of $\\Upsilon(1S,2S,3S)\\to \\eta_c+h_c(^1P_1)$ are predicted to be around $10^{-6}$, which shall be tested in future Belle experiments.

  13. Thermophysical Properties of Hydrocarbon Mixtures

    Science.gov (United States)

    SRD 4 NIST Thermophysical Properties of Hydrocarbon Mixtures (PC database for purchase)   Interactive computer program for predicting thermodynamic and transport properties of pure fluids and fluid mixtures containing up to 20 components. The components are selected from a database of 196 components, mostly hydrocarbons.

  14. Hydrocarbon Receptor Pathway in Dogs

    NARCIS (Netherlands)

    Steenbeek, F.G. van; Spee, B.; Penning, L.C.; Kummeling, A.; Gils, I.H.M.; Grinwis, G.C.M.; Leenen, D. van; Holstege, F.C.P.; Vos-Loohuis, M.; Rothuizen, J.; Leegwater, P.A.J.

    2013-01-01

    The aryl hydrocarbon receptor (AHR) mediates biological responses to toxic chemicals. An unexpected role for AHR in vascularization was suggested when mice lacking AHR displayed impaired closure of the ductus venosus after birth, as did knockout mice for aryl hydrocarbon receptor interacting protein

  15. Hydrocarbon Receptor Pathway in Dogs

    NARCIS (Netherlands)

    Steenbeek, F.G. van; Spee, B.; Penning, L.C.; Kummeling, A.; Gils, I.H.M.; Grinwis, G.C.M.; Leenen, D. van; Holstege, F.C.P.; Vos-Loohuis, M.; Rothuizen, J.; Leegwater, P.A.J.

    The aryl hydrocarbon receptor (AHR) mediates biological responses to toxic chemicals. An unexpected role for AHR in vascularization was suggested when mice lacking AHR displayed impaired closure of the ductus venosus after birth, as did knockout mice for aryl hydrocarbon receptor interacting

  16. Global analysis of ankyrin repeat domain C3HC4-type RING finger gene family in plants.

    Directory of Open Access Journals (Sweden)

    Xiaowei Yuan

    Full Text Available Ankyrin repeat (ANK C3HC4-type RING finger (RF genes comprise a large family in plants and play important roles in various physiological processes of plant life. In this study, we identified 187 ANK C3HC4-type RF proteins from 29 species with complete genomes and named the ANK C3HC4-type RF proteins the XB3-like proteins because they are structurally related to the rice (Oryza sativa XB3. A phylogenetic relationship analysis suggested that the XB3-like genes originated from ferns, and the encoded proteins fell into 3 major groups. Among these groups, we found that the spacing between the metal ligand position 6 and 7, and the conserved residues, which was in addition to the metal ligand amino acids, in the C3HC4-type RF were different. Using a wide range of protein structural analyses, protein models were established, and all XB3-like proteins were found to contain two to seven ANKs and a C3HC4-type RF. The microarray data for the XB3-like genes of Arabidopsis, Oryza sative, Zea mays and Glycine max revealed that the expression of XB3-like genes was in different tissues and during different life stages. The preferential expression of XB3-like genes in specified tissues and the response to phytohormone and abiotic stress treatments of Arabidopsis and Zea mays not only confirmed the microarray analysis data but also demonstrated that the XB3-like proteins play roles in plant growth and development as well as in stress responses. Our data provide a very useful reference for the identification and functional analysis of members of this gene family and also provide a new method for the genome-wide analysis of gene families.

  17. Cold exposure increases slow-type myosin heavy chain 1 (MyHC1) composition of soleus muscle in rats.

    Science.gov (United States)

    Mizunoya, Wataru; Iwamoto, Yohei; Sato, Yusuke; Tatsumi, Ryuichi; Ikeuchi, Yoshihide

    2014-03-01

    The aim of this study was to examine the effects of cold exposure on rat skeletal muscle fiber type, according to myosin heavy chain (MyHC) isoform and metabolism-related factors. Male Wistar rats (7 weeks old) were housed individually at 4 ± 2°C as a cold-exposed group or at room temperature (22 ± 2°C) as a control group for 4 weeks. We found that cold exposure significantly increased the slow-type MyHC1 content in the soleus muscle (a typical slow-type fiber), while the intermediate-type MyHC2A content was significantly decreased. In contrast to soleus, MyHC composition of extensor digitorum longus (EDL, a typical fast-type fiber) and gastrocnemius (a mix of slow-type and fast-type fibers) muscle did not change from cold exposure. Cold exposure increased mRNA expression of mitochondrial uncoupling protein 3 (UCP3) in both the soleus and EDL. Cold exposure also increased mRNA expression of myoglobin, peroxisome proliferator-activated receptor gamma coactivator 1α (PGC1α) and forkhead box O1 (FOXO1) in the soleus. Upregulation of UCP3 and PGC1α proteins were observed with Western blotting in the gastrocnemius. Thus, cold exposure increased metabolism-related factors in all muscle types that were tested, but MyHC isoforms changed only in the soleus. © 2013 Japanese Society of Animal Science.

  18. Limitations of microbial hydrocarbon degradation at the Amon mud volcano (Nile deep-sea fan

    Directory of Open Access Journals (Sweden)

    J. Felden

    2013-05-01

    Full Text Available The Amon mud volcano (MV, located at 1250 m water depth on the Nile deep-sea fan, is known for its active emission of methane and non-methane hydrocarbons into the hydrosphere. Previous investigations showed a low efficiency of hydrocarbon-degrading anaerobic microbial communities inhabiting the Amon MV center in the presence of sulfate and hydrocarbons in the seeping subsurface fluids. By comparing spatial and temporal patterns of in situ biogeochemical fluxes, temperature gradients, pore water composition, and microbial activities over 3 yr, we investigated why the activity of anaerobic hydrocarbon degraders can be low despite high energy supplies. We found that the central dome of the Amon MV, as well as a lateral mud flow at its base, showed signs of recent exposure of hot subsurface muds lacking active hydrocarbon degrading communities. In these highly disturbed areas, anaerobic degradation of methane was less than 2% of the methane flux. Rather high oxygen consumption rates compared to low sulfide production suggest a faster development of more rapidly growing aerobic hydrocarbon degraders in highly disturbed areas. In contrast, the more stabilized muds surrounding the central gas and fluid conduits hosted active anaerobic hydrocarbon-degrading microbial communities. The low microbial activity in the hydrocarbon-vented areas of Amon MV is thus a consequence of kinetic limitations by heat and mud expulsion, whereas most of the outer MV area is limited by hydrocarbon transport.

  19. Polycyclic Aromatic Hydrocarbons in Fine Particulate Matter Emitted from Burning Kerosene, Liquid Petroleum Gas, and Wood Fuels in Household Cookstoves

    Science.gov (United States)

    This study measured polycyclic aromatic hydrocarbon (PAH) composition in particulate matter emissions from residential cookstoves. A variety of fuel and cookstove combinations were examined, including: (i) liquid petroleum gas (LPG), (ii) kerosene in a wick stove, (iii) wood (10%...

  20. Systematic differences in electrochemical reduction of the structurally characterized anti-cancer platinum(IV) complexes [Pt{((p-HC6F4)NCH2)2}-(pyridine)2Cl2], [Pt{((p-HC6F4)NCH2)2}(pyridine)2(OH)2], and [Pt{((p-HC6F4)NCH2)2}(pyridine)2(OH)Cl].

    Science.gov (United States)

    Guo, Si-Xuan; Mason, Dayna N; Turland, Susan A; Lawrenz, Eric T; Kelly, Lance C; Fallon, Gary D; Gatehouse, Bryan M; Bond, Alan M; Deacon, Glen B; Battle, Andrew R; Hambley, Trevor W; Rainone, Silvina; Webster, Lorraine K; Cullinane, Carleen

    2012-10-01

    The putative platinum(IV) anticancer drugs, [Pt{((R)NCH(2))(2)}(py)(2)XY] (X,Y=Cl, R=p-HC(6)F(4) (1a), C(6)F(5) (1b); X,Y=OH, R=p-HC(6)F(4) (2); X=Cl, Y=OH, R=p-HC(6)F(4) (3), py = pyridine) have been prepared by oxidation of the Pt(II) anticancer drugs [Pt{((R)NCH(2))(2)}(py)(2)] (R=p-HC