40 CFR 62.1115 - Identification of sources.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Landfill Gas Emissions from Existing Municipal Solid Waste Landfills § 62.1115 Identification of sources. The plan applies to existing municipal solid waste landfills for which construction, reconstruction...

40 CFR 62.2360 - Identification of sources.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Landfill Gas Emissions from Existing Municipal Solid Waste Landfills § 62.2360 Identification of sources. The plan applies to existing municipal solid waste landfills for which construction, reconstruction...

40 CFR 62.3631 - Identification of sources.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Landfill Gas Emissions from Existing Municipal Solid Waste Landfills § 62.3631 Identification of sources. The plan applies to all existing municipal solid waste landfills for which construction...

40 CFR 62.601 - Identification of sources.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Landfill Gas Emissions from Existing Municipal Solid Waste Landfills § 62.601 Identification of sources. The plan applies to all existing municipal solid waste landfills for which construction...

40 CFR 62.103 - Identification of sources.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Landfill Gas Emissions from Existing Municipal Solid Waste Landfills § 62.103 Identification of sources. The plan applies to existing municipal solid waste landfills for which construction, reconstruction...

40 CFR 62.2607 - Identification of sources.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Landfill Gas Emissions from Existing Municipal Solid Waste Landfills § 62.2607 Identification of sources. The plan applies to existing municipal solid waste landfills for which construction, reconstruction...

40 CFR 62.5861 - Identification of sources.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Landfill Gas Emissions from Existing Municipal Solid Waste Landfills § 62.5861 Identification of sources. The plan applies to all existing municipal solid waste landfills for which construction...

40 CFR 62.6601 - Identification of sources.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Landfill Gas Emissions from Existing Municipal Solid Waste Landfills § 62.6601 Identification of sources. The plan applies to all existing municipal solid waste landfills for which construction...

40 CFR 62.3331 - Identification of sources.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Landfill Gas Emissions from Existing Municipal Solid Waste Landfills § 62.3331 Identification of sources. The plan applies to all existing municipal solid waste landfills for which construction...

40 CFR 62.8601 - Identification of sources.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Landfill Gas Emissions from Existing Municipal Solid Waste Landfills § 62.8601 Identification of sources. The plan applies to all existing municipal solid waste landfills for which construction...

40 CFR 62.1101 - Identification of sources.

Code of Federal Regulations, 2014 CFR

2014-07-01

... Fluoride Emissions from Existing Phosphate Fertilizer Plants § 62.1101 Identification of sources. The plan applies to existing facilities at the following phosphate fertilizer plants: (a) Occidental Chemical...

40 CFR 62.6351 - Identification of sources.

Code of Federal Regulations, 2014 CFR

2014-07-01

... Fluoride Emissions from Existing Phosphate Fertilizer Plants § 62.6351 Identification of sources. The plan applies to existing facilities at the following phosphate fertilizer plant: Farmers Chemical Company...

40 CFR 62.6351 - Identification of sources.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Fluoride Emissions from Existing Phosphate Fertilizer Plants § 62.6351 Identification of sources. The plan applies to existing facilities at the following phosphate fertilizer plant: Farmers Chemical Company...

40 CFR 62.6351 - Identification of sources.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Fluoride Emissions from Existing Phosphate Fertilizer Plants § 62.6351 Identification of sources. The plan applies to existing facilities at the following phosphate fertilizer plant: Farmers Chemical Company...

40 CFR 62.6351 - Identification of sources.

Code of Federal Regulations, 2013 CFR

2013-07-01

... Fluoride Emissions from Existing Phosphate Fertilizer Plants § 62.6351 Identification of sources. The plan applies to existing facilities at the following phosphate fertilizer plant: Farmers Chemical Company...

40 CFR 62.6351 - Identification of sources.

Code of Federal Regulations, 2012 CFR

2012-07-01

... Fluoride Emissions from Existing Phosphate Fertilizer Plants § 62.6351 Identification of sources. The plan applies to existing facilities at the following phosphate fertilizer plant: Farmers Chemical Company...

40 CFR 62.1101 - Identification of sources.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Fluoride Emissions from Existing Phosphate Fertilizer Plants § 62.1101 Identification of sources. The plan applies to existing facilities at the following phosphate fertilizer plants: (a) Occidental Chemical...

40 CFR 62.1101 - Identification of sources.

Code of Federal Regulations, 2012 CFR

2012-07-01

... Fluoride Emissions from Existing Phosphate Fertilizer Plants § 62.1101 Identification of sources. The plan applies to existing facilities at the following phosphate fertilizer plants: (a) Occidental Chemical...

40 CFR 62.1101 - Identification of sources.

Code of Federal Regulations, 2013 CFR

2013-07-01

... Fluoride Emissions from Existing Phosphate Fertilizer Plants § 62.1101 Identification of sources. The plan applies to existing facilities at the following phosphate fertilizer plants: (a) Occidental Chemical...

40 CFR 62.1101 - Identification of sources.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Fluoride Emissions from Existing Phosphate Fertilizer Plants § 62.1101 Identification of sources. The plan applies to existing facilities at the following phosphate fertilizer plants: (a) Occidental Chemical...

40 CFR 62.601 - Identification of sources.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Landfill Gas Emissions from Existing Municipal Solid Waste Landfills § 62.601 Identification of sources. The plan applies to all existing municipal solid waste landfills for which construction...

Approach to identifying pollutant source and matching flow field

NASA Astrophysics Data System (ADS)

Liping, Pang; Yu, Zhang; Hongquan, Qu; Tao, Hu; Wei, Wang

2013-07-01

Accidental pollution events often threaten people's health and lives, and it is necessary to identify a pollutant source rapidly so that prompt actions can be taken to prevent the spread of pollution. But this identification process is one of the difficulties in the inverse problem areas. This paper carries out some studies on this issue. An approach using single sensor information with noise was developed to identify a sudden continuous emission trace pollutant source in a steady velocity field. This approach first compares the characteristic distance of the measured concentration sequence to the multiple hypothetical measured concentration sequences at the sensor position, which are obtained based on a source-three-parameter multiple hypotheses. Then we realize the source identification by globally searching the optimal values with the objective function of the maximum location probability. Considering the large amount of computation load resulting from this global searching, a local fine-mesh source search method based on priori coarse-mesh location probabilities is further used to improve the efficiency of identification. Studies have shown that the flow field has a very important influence on the source identification. Therefore, we also discuss the impact of non-matching flow fields with estimation deviation on identification. Based on this analysis, a method for matching accurate flow field is presented to improve the accuracy of identification. In order to verify the practical application of the above method, an experimental system simulating a sudden pollution process in a steady flow field was set up and some experiments were conducted when the diffusion coefficient was known. The studies showed that the three parameters (position, emission strength and initial emission time) of the pollutant source in the experiment can be estimated by using the method for matching flow field and source identification.

40 CFR 62.9500 - Identification of sources.

Code of Federal Regulations, 2014 CFR

2014-07-01

... (CONTINUED) APPROVAL AND PROMULGATION OF STATE PLANS FOR DESIGNATED FACILITIES AND POLLUTANTS Oregon Fluoride Emissions from Phosphate Fertilizer Plants § 62.9500 Identification of sources. The Oregon State Department...

40 CFR 62.7400 - Identification of sources-negative declaration.

Code of Federal Regulations, 2012 CFR

2012-07-01

... PROGRAMS (CONTINUED) APPROVAL AND PROMULGATION OF STATE PLANS FOR DESIGNATED FACILITIES AND POLLUTANTS New Hampshire Fluoride Emissions from Existing Primary Aluminum Plants § 62.7400 Identification of sources...

40 CFR 62.7400 - Identification of sources-negative declaration.

Code of Federal Regulations, 2010 CFR

2010-07-01

... PROGRAMS (CONTINUED) APPROVAL AND PROMULGATION OF STATE PLANS FOR DESIGNATED FACILITIES AND POLLUTANTS New Hampshire Fluoride Emissions from Existing Primary Aluminum Plants § 62.7400 Identification of sources...

40 CFR 62.7400 - Identification of sources-negative declaration.

Code of Federal Regulations, 2013 CFR

2013-07-01

... PROGRAMS (CONTINUED) APPROVAL AND PROMULGATION OF STATE PLANS FOR DESIGNATED FACILITIES AND POLLUTANTS New Hampshire Fluoride Emissions from Existing Primary Aluminum Plants § 62.7400 Identification of sources...

40 CFR 62.7400 - Identification of sources-negative declaration.

Code of Federal Regulations, 2014 CFR

2014-07-01

... PROGRAMS (CONTINUED) APPROVAL AND PROMULGATION OF STATE PLANS FOR DESIGNATED FACILITIES AND POLLUTANTS New Hampshire Fluoride Emissions from Existing Primary Aluminum Plants § 62.7400 Identification of sources...

40 CFR 62.7400 - Identification of sources-negative declaration.

Code of Federal Regulations, 2011 CFR

2011-07-01

... PROGRAMS (CONTINUED) APPROVAL AND PROMULGATION OF STATE PLANS FOR DESIGNATED FACILITIES AND POLLUTANTS New Hampshire Fluoride Emissions from Existing Primary Aluminum Plants § 62.7400 Identification of sources...

40 CFR 62.4631 - Identification of Sources.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Landfill Gas Emissions from Existing Municipal Solid Waste Landfills § 62.4631 Identification of Sources. The plan applies to all existing municipal solid waste landfills with design capacities greater than 2...

40 CFR 62.9510 - Identification of sources.

Code of Federal Regulations, 2010 CFR

2010-07-01

... of Landfill Gas Emissions from Existing Municipal Solid Waste Landfills § 62.9510 Identification of sources. The plan applies to all existing MSW landfill facilities in Oregon meeting the requirements as...

40 CFR 62.5151 - Identification of sources.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Landfill Gas Emissions from Existing Municipal Solid Waste Landfills (section 111(d) Plan) § 62.5151 Identification of sources. The plan applies to all Maryland existing municipal solid waste landfills for which...

40 CFR 62.1951 - Identification of sources.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Landfill Gas Emissions from Existing Municipal Solid Waste Landfills (section 111(d) Plan) § 62.1951 Identification of sources. The plan applies to all Delaware existing municipal solid waste landfills for which...

40 CFR 62.7860 - Identification of sources-negative declaration.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Mexico Emissions from Existing Large Municipal Waste Combustion Units § 62.7860 Identification of sources... lands under the jurisdiction of the Albuquerque/Bernalillo county Air Quality Control Board subject to...

40 CFR 62.7860 - Identification of sources-negative declaration.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Mexico Emissions from Existing Large Municipal Waste Combustion Units § 62.7860 Identification of sources... lands under the jurisdiction of the Albuquerque/Bernalillo county Air Quality Control Board subject to...

40 CFR 62.9500 - Identification of sources.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Emissions from Phosphate Fertilizer Plants § 62.9500 Identification of sources. The Oregon State Department... phosphate fertilizer plants in the State subject to part 60, subpart B of this chapter. [44 FR 76281, Dec...

40 CFR 62.9500 - Identification of sources.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Emissions from Phosphate Fertilizer Plants § 62.9500 Identification of sources. The Oregon State Department... phosphate fertilizer plants in the State subject to part 60, subpart B of this chapter. [44 FR 76281, Dec...

40 CFR 62.10602 - Identification of sources-negative declaration.

Code of Federal Regulations, 2011 CFR

2011-07-01

... POLLUTANTS Tennessee Fluoride Emissions from Phosphate Fertilizer Plants § 62.10602 Identification of sources... letter certifying that there are no existing phosphate fertilizer plants in the State subject to part 60...

40 CFR 62.10602 - Identification of sources-negative declaration.

Code of Federal Regulations, 2010 CFR

2010-07-01

... POLLUTANTS Tennessee Fluoride Emissions from Phosphate Fertilizer Plants § 62.10602 Identification of sources... letter certifying that there are no existing phosphate fertilizer plants in the State subject to part 60...

40 CFR 62.103 - Identification of sources.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Landfill Gas Emissions from Existing Municipal Solid Waste Landfills § 62.103 Identification of sources. The plan applies to existing municipal solid waste landfills for which construction, reconstruction... Tons Per Day of Municipal Solid Waste ...

Development of unauthorized airborne emission source identification procedure

NASA Astrophysics Data System (ADS)

Shtripling, L. O.; Bazhenov, V. V.; Varakina, N. S.; Kupriyanova, N. P.

2018-01-01

The paper presents the procedure for searching sources of unauthorized airborne emissions. To make reasonable regulation decisions on airborne pollutant emissions and to ensure the environmental safety of population, the procedure provides for the determination of a pollutant mass emission value from the source being the cause of high pollution level and the search of a previously unrecognized contamination source in a specified area. To determine the true value of mass emission from the source, the minimum of the mean-root-square mismatch criterion between the computed and measured pollutant concentration in the given location is used.

Source identification of individual soot agglomerates in Arctic air by transmission electron microscopy

NASA Astrophysics Data System (ADS)

Weinbruch, S.; Benker, N.; Kandler, K.; Schütze, K.; Kling, K.; Berlinger, B.; Thomassen, Y.; Drotikova, T.; Kallenborn, R.

2018-01-01

Individual soot agglomerates collected at four different locations on the Arctic archipelago Svalbard (Norway) were characterised by transmission electron microscopy and energy-dispersive X-ray microanalysis. For source identification of the ambient soot agglomerates, samples from different local sources (coal burning power plants in Longyearbyen and Barentsburg, diesel and oil burning for power generation in Sveagruva and Ny Ålesund, cruise ship) as well as from other sources which may contribute to Arctic soot concentrations (biomass burning, aircraft emissions, diesel engines) were investigated. Diameter and graphene sheet separation distance of soot primary particles were found to be highly variable within each source and are not suited for source identification. In contrast, concentrations of the minor elements Si, P, K, Ca and Fe showed significant differences which can be used for source attribution. The presence/absence of externally mixed particle groups (fly ashes, tar balls, mercury particles) gives additional hints about the soot sources. Biomass/wood burning, ship emissions and coal burning in Barentsburg can be excluded as major source for ambient soot at Svalbard. The coal power plant in Longyearbyen is most likely a major source of soot in the settlement of Longyearbyen but does not contribute significantly to soot collected at the Global Atmosphere Watch station Zeppelin Mountain near Ny Ålesund. The most probable soot sources at Svalbard are aircraft emissions and diesel exhaust as well as long range transport of coal burning emissions.

40 CFR 62.2605 - Identification of sources-negative declaration.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Georgia Fluoride Emissions from Existing Primary Aluminum Reduction Plants § 62.2605 Identification of... 19, 1983, certifying that there are no existing primary aluminum reduction plants in the State of... Gases, Organic Compounds and Nitrogen Oxide Emissions From Existing Municipal Waste Combustors With the...

40 CFR 62.2605 - Identification of sources-negative declaration.

Code of Federal Regulations, 2013 CFR

2013-07-01

... Georgia Fluoride Emissions from Existing Primary Aluminum Reduction Plants § 62.2605 Identification of... 19, 1983, certifying that there are no existing primary aluminum reduction plants in the State of... Gases, Organic Compounds and Nitrogen Oxide Emissions From Existing Municipal Waste Combustors With the...

40 CFR 62.2605 - Identification of sources-negative declaration.

Code of Federal Regulations, 2014 CFR

2014-07-01

... Georgia Fluoride Emissions from Existing Primary Aluminum Reduction Plants § 62.2605 Identification of... 19, 1983, certifying that there are no existing primary aluminum reduction plants in the State of... Gases, Organic Compounds and Nitrogen Oxide Emissions From Existing Municipal Waste Combustors With the...

40 CFR 62.2605 - Identification of sources-negative declaration.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Georgia Fluoride Emissions from Existing Primary Aluminum Reduction Plants § 62.2605 Identification of... 19, 1983, certifying that there are no existing primary aluminum reduction plants in the State of... Gases, Organic Compounds and Nitrogen Oxide Emissions From Existing Municipal Waste Combustors With the...

40 CFR 62.2605 - Identification of sources-negative declaration.

Code of Federal Regulations, 2012 CFR

2012-07-01

... Georgia Fluoride Emissions from Existing Primary Aluminum Reduction Plants § 62.2605 Identification of... 19, 1983, certifying that there are no existing primary aluminum reduction plants in the State of... Gases, Organic Compounds and Nitrogen Oxide Emissions From Existing Municipal Waste Combustors With the...

Source apportionment of PAH in Hamilton Harbour suspended sediments: comparison of two factor analysis methods.

PubMed

Sofowote, Uwayemi M; McCarry, Brian E; Marvin, Christopher H

2008-08-15

A total of 26 suspended sediment samples collected over a 5-year period in Hamilton Harbour, Ontario, Canada and surrounding creeks were analyzed for a suite of polycyclic aromatic hydrocarbons and sulfur heterocycles. Hamilton Harbour sediments contain relatively high levels of polycyclic aromatic compounds and heavy metals due to emissions from industrial and mobile sources. Two receptor modeling methods using factor analyses were compared to determine the profiles and relative contributions of pollution sources to the harbor; these methods are principal component analyses (PCA) with multiple linear regression analysis (MLR) and positive matrix factorization (PMF). Both methods identified four factors and gave excellent correlation coefficients between predicted and measured levels of 25 aromatic compounds; both methods predicted similar contributions from coal tar/coal combustion sources to the harbor (19 and 26%, respectively). One PCA factor was identified as contributions from vehicular emissions (61%); PMF was able to differentiate vehicular emissions into two factors, one attributed to gasoline emissions sources (28%) and the other to diesel emissions sources (24%). Overall, PMF afforded better source identification than PCA with MLR. This work constitutes one of the few examples of the application of PMF to the source apportionment of sediments; the addition of sulfur heterocycles to the analyte list greatly aided in the source identification process.

The identification of Volatile Organic Compound's emission sources in indoor air of living spaces, offices and laboratories

NASA Astrophysics Data System (ADS)

Kultys, Beata

2018-01-01

Indoor air quality is important because people spend most of their time in closed rooms. If volatile organic compounds (VOCs) are present at elevated concentrations, they may cause a deterioration in human well-being or health. The identification of indoor emission sources is carried out by comparison indoor and outdoor air composition. The aim of the study was to determinate the concentration of VOCs in indoor air, where there was a risk of elevated levels due to the kind of work type carried out or the users complained about the symptoms of a sick building followed by an appropriate interpretation of the results to determine whether the source of the emission in the tested room occurs. The air from residential, office and laboratory was tested in this study. The identification of emission sources was based on comparison of indoor and outdoor VOCs concentration and their correlation coefficients. The concentration of VOCs in all the rooms were higher or at a similar level to that of the air sampled at the same time outside the building. Human activity, in particular repair works and experiments with organic solvents, has the greatest impact on deterioration of air quality.

40 CFR 62.10627 - Identification of sources.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 8 2010-07-01 2010-07-01 false Identification of sources. 62.10627 Section 62.10627 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS... Metals, Acid Gases, Organic Compounds and Nitrogen Oxide Emissions from Existing Municipal Waste...

40 CFR 62.3651 - Identification of sources.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 8 2010-07-01 2010-07-01 false Identification of sources. 62.3651 Section 62.3651 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS..., Acid Gases, Organic Compounds and Nitrogen Oxide Emissions from Existing Municipal Waste Combustors...

40 CFR 62.5111 - Identification of sources.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 8 2010-07-01 2010-07-01 false Identification of sources. 62.5111 Section 62.5111 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS..., Acid Gases, Organic Compounds and Nitrogen Oxide Emissions from Existing Municipal Waste Combustors...

40 CFR 62.10150 - Identification of sources.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 8 2010-07-01 2010-07-01 false Identification of sources. 62.10150 Section 62.10150 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS... Metals, Acid Gases, Organic Compounds and Nitrogen Oxide Emissions from Existing Municipal Waste...

40 CFR 62.9150 - Identification of sources.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 8 2010-07-01 2010-07-01 false Identification of sources. 62.9150 Section 62.9150 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS..., Acid Gases, Organic Compounds and Nitrogen Oxide Emissions from Existing Municipal Waste Combustors...

40 CFR 62.9641 - Identification of sources.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 8 2010-07-01 2010-07-01 false Identification of sources. 62.9641 Section 62.9641 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS... Metals, Acid Gases, Organic Compounds and Nitrogen Oxide Emissions from Existing Municipal Waste...

40 CFR 62.2355 - Identification of sources.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 8 2010-07-01 2010-07-01 false Identification of sources. 62.2355 Section 62.2355 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS..., Acid Gases, Organic Compounds and Nitrogen Oxide Emissions from Existing Municipal Waste Combustors...

40 CFR 62.3341 - Identification of sources.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 8 2010-07-01 2010-07-01 false Identification of sources. 62.3341 Section 62.3341 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS..., Acid Gases, Organic Compounds and Nitrogen Oxide Emissions from Existing Hospital / Medical Infectious...

40 CFR 62.2606 - Identification of sources.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 8 2010-07-01 2010-07-01 false Identification of sources. 62.2606 Section 62.2606 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS..., Acid Gases, Organic Compounds and Nitrogen Oxide Emissions from Existing Municipal Waste Combustors...

40 CFR 62.3641 - Identification of sources.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 8 2010-07-01 2010-07-01 false Identification of sources. 62.3641 Section 62.3641 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS..., Acid Gases, Organic Compounds and Nitrogen Oxide Emissions from Existing Hospital/medical Infectious...

40 CFR 62.4975 - Identification of sources.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 8 2010-07-01 2010-07-01 false Identification of sources. 62.4975 Section 62.4975 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS..., Acid Gases, Organic Compounds and Nitrogen Oxide Emissions from Existing Municipal Waste Combustors...

40 CFR 62.104 - Identification of sources.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 8 2010-07-01 2010-07-01 false Identification of sources. 62.104 Section 62.104 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS..., Acid Gases, Organic Compounds and Nitrogen Oxide Emissions from Existing Municipal Waste Combustors...

40 CFR 62.9505 - Identification of sources.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 8 2010-07-01 2010-07-01 false Identification of sources. 62.9505 Section 62.9505 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS..., Acid Gases, Organic Compounds and Nitrogen Oxide Emissions from Existing Municipal Waste Combustors...

40 CFR 62.11870 - Identification of sources.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 8 2010-07-01 2010-07-01 false Identification of sources. 62.11870 Section 62.11870 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS... Metals, Acid Gases, Organic Compounds and Nitrogen Oxide Emissions from Existing Municipal Waste...

40 CFR 62.5425 - Identification of sources.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 8 2010-07-01 2010-07-01 false Identification of sources. 62.5425 Section 62.5425 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS... Metals, Acid Gases, Organic Compounds and Nitrogen Oxide Emissions from Existing Municipal Waste...

40 CFR 62.9140 - Identification of source.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 8 2010-07-01 2010-07-01 false Identification of source. 62.9140 Section 62.9140 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS...] Metals, Acid Gases, Organic Compounds and Nitrogen Oxide Emissions From Existing Municipal Waste...

40 CFR 62.6353 - Identification of sources.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 40 Protection of Environment 9 2014-07-01 2014-07-01 false Identification of sources. 62.6353 Section 62.6353 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS... Company, Joplin, Missouri Total Reduced Sulfur Emissions From Existing Kraft Pulp Mills ...

40 CFR 62.6353 - Identification of sources.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 9 2012-07-01 2012-07-01 false Identification of sources. 62.6353 Section 62.6353 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS... Company, Joplin, Missouri Total Reduced Sulfur Emissions From Existing Kraft Pulp Mills ...

40 CFR 62.6353 - Identification of sources.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 40 Protection of Environment 9 2013-07-01 2013-07-01 false Identification of sources. 62.6353 Section 62.6353 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS... Company, Joplin, Missouri Total Reduced Sulfur Emissions From Existing Kraft Pulp Mills ...

40 CFR 62.4625 - Identification of sources.

Code of Federal Regulations, 2012 CFR

2012-07-01

... Fluoride Emissions from Existing Phosphate Fertilizer Plants § 62.4625 Identification of sources. (a) The Plan applies to existing facilities at the following phosphate fertilizer plants: (1) Agrico Chemical Company at Donaldsville, Louisiana. (2) Allied Chemical Corporation at Geismar, Louisiana. (3) Beker...

40 CFR 62.4625 - Identification of sources.

Code of Federal Regulations, 2013 CFR

2013-07-01

... Fluoride Emissions from Existing Phosphate Fertilizer Plants § 62.4625 Identification of sources. (a) The Plan applies to existing facilities at the following phosphate fertilizer plants: (1) Agrico Chemical Company at Donaldsville, Louisiana. (2) Allied Chemical Corporation at Geismar, Louisiana. (3) Beker...

40 CFR 62.4625 - Identification of sources.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Fluoride Emissions from Existing Phosphate Fertilizer Plants § 62.4625 Identification of sources. (a) The Plan applies to existing facilities at the following phosphate fertilizer plants: (1) Agrico Chemical Company at Donaldsville, Louisiana. (2) Allied Chemical Corporation at Geismar, Louisiana. (3) Beker...

40 CFR 62.4625 - Identification of sources.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Fluoride Emissions from Existing Phosphate Fertilizer Plants § 62.4625 Identification of sources. (a) The Plan applies to existing facilities at the following phosphate fertilizer plants: (1) Agrico Chemical Company at Donaldsville, Louisiana. (2) Allied Chemical Corporation at Geismar, Louisiana. (3) Beker...

40 CFR 62.4625 - Identification of sources.

Code of Federal Regulations, 2014 CFR

2014-07-01

... Fluoride Emissions from Existing Phosphate Fertilizer Plants § 62.4625 Identification of sources. (a) The Plan applies to existing facilities at the following phosphate fertilizer plants: (1) Agrico Chemical Company at Donaldsville, Louisiana. (2) Allied Chemical Corporation at Geismar, Louisiana. (3) Beker...

40 CFR 62.6110 - Identification of sources.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Sulfuric Acid Mist from Existing Sulfuric Acid Plants § 62.6110 Identification of sources. The plan applies to existing plants at the following locations: Sulfur burning plant and oleum plant of Mississippi Chemical Corporation in Pascagoula. Fluoride Emissions From Phosphate Fertilizer Plants ...

40 CFR 62.6110 - Identification of sources.

Code of Federal Regulations, 2013 CFR

2013-07-01

... Sulfuric Acid Mist from Existing Sulfuric Acid Plants § 62.6110 Identification of sources. The plan applies to existing plants at the following locations: Sulfur burning plant and oleum plant of Mississippi Chemical Corporation in Pascagoula. Fluoride Emissions From Phosphate Fertilizer Plants ...

40 CFR 62.6110 - Identification of sources.

Code of Federal Regulations, 2014 CFR

2014-07-01

... Sulfuric Acid Mist from Existing Sulfuric Acid Plants § 62.6110 Identification of sources. The plan applies to existing plants at the following locations: Sulfur burning plant and oleum plant of Mississippi Chemical Corporation in Pascagoula. Fluoride Emissions From Phosphate Fertilizer Plants ...

40 CFR 62.6110 - Identification of sources.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Sulfuric Acid Mist from Existing Sulfuric Acid Plants § 62.6110 Identification of sources. The plan applies to existing plants at the following locations: Sulfur burning plant and oleum plant of Mississippi Chemical Corporation in Pascagoula. Fluoride Emissions From Phosphate Fertilizer Plants ...

40 CFR 62.6110 - Identification of sources.

Code of Federal Regulations, 2012 CFR

2012-07-01

... Sulfuric Acid Mist from Existing Sulfuric Acid Plants § 62.6110 Identification of sources. The plan applies to existing plants at the following locations: Sulfur burning plant and oleum plant of Mississippi Chemical Corporation in Pascagoula. Fluoride Emissions From Phosphate Fertilizer Plants ...

40 CFR 62.8871 - Identification of sources.

Code of Federal Regulations, 2010 CFR

2010-07-01

... (CONTINUED) APPROVAL AND PROMULGATION OF STATE PLANS FOR DESIGNATED FACILITIES AND POLLUTANTS Ohio Landfill Gas Emissions from Existing Municipal Solid Waste Landfills § 62.8871 Identification of sources. The plan applies to all existing municipal solid waste landfills for which construction, reconstruction or...

40 CFR 62.7101 - Identification of sources.

Code of Federal Regulations, 2010 CFR

2010-07-01

... (CONTINUED) APPROVAL AND PROMULGATION OF STATE PLANS FOR DESIGNATED FACILITIES AND POLLUTANTS Nevada Landfill Gas Emissions from Existing Municipal Solid Waste Landfills § 62.7101 Identification of sources. The plan applies to all existing municipal solid waste landfills for which construction, reconstruction, or...

40 CFR 62.3852 - Identification of sources.

Code of Federal Regulations, 2013 CFR

2013-07-01

... Emissions from Existing Phosphate Fertilizer Plants § 62.3852 Identification of sources. (a) The plan applies to existing facilities at the following phosphate fertilizer plants: (1) Agrico Chemical Company, Fort Madison, Iowa. (2) Chevron Chemical Company, Fort Madison, Iowa. (3) Occidental Chemical Company...

40 CFR 62.3852 - Identification of sources.

Code of Federal Regulations, 2014 CFR

2014-07-01

... Emissions from Existing Phosphate Fertilizer Plants § 62.3852 Identification of sources. (a) The plan applies to existing facilities at the following phosphate fertilizer plants: (1) Agrico Chemical Company, Fort Madison, Iowa. (2) Chevron Chemical Company, Fort Madison, Iowa. (3) Occidental Chemical Company...

40 CFR 62.3852 - Identification of sources.

Code of Federal Regulations, 2012 CFR

2012-07-01

... Emissions from Existing Phosphate Fertilizer Plants § 62.3852 Identification of sources. (a) The plan applies to existing facilities at the following phosphate fertilizer plants: (1) Agrico Chemical Company, Fort Madison, Iowa. (2) Chevron Chemical Company, Fort Madison, Iowa. (3) Occidental Chemical Company...

40 CFR 62.3851 - Identification of sources.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Acid Mist from Existing Sulfuric Acid Production Plants § 62.3851 Identification of sources. (a) The plan applies to existing facilities at the following sulfuric acid production plants: (1) Agrico Chemical Company, Fort Madison, Iowa (2) Koch Sulfur Products Company, Dubuque, Iowa Fluoride Emissions...

40 CFR 62.3851 - Identification of sources.

Code of Federal Regulations, 2012 CFR

2012-07-01

... Acid Mist from Existing Sulfuric Acid Production Plants § 62.3851 Identification of sources. (a) The plan applies to existing facilities at the following sulfuric acid production plants: (1) Agrico Chemical Company, Fort Madison, Iowa (2) Koch Sulfur Products Company, Dubuque, Iowa Fluoride Emissions...

40 CFR 62.3851 - Identification of sources.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Acid Mist from Existing Sulfuric Acid Production Plants § 62.3851 Identification of sources. (a) The plan applies to existing facilities at the following sulfuric acid production plants: (1) Agrico Chemical Company, Fort Madison, Iowa (2) Koch Sulfur Products Company, Dubuque, Iowa Fluoride Emissions...

40 CFR 62.3851 - Identification of sources.

Code of Federal Regulations, 2013 CFR

2013-07-01

... Acid Mist from Existing Sulfuric Acid Production Plants § 62.3851 Identification of sources. (a) The plan applies to existing facilities at the following sulfuric acid production plants: (1) Agrico Chemical Company, Fort Madison, Iowa (2) Koch Sulfur Products Company, Dubuque, Iowa Fluoride Emissions...

40 CFR 62.3851 - Identification of sources.

Code of Federal Regulations, 2014 CFR

2014-07-01

... Acid Mist from Existing Sulfuric Acid Production Plants § 62.3851 Identification of sources. (a) The plan applies to existing facilities at the following sulfuric acid production plants: (1) Agrico Chemical Company, Fort Madison, Iowa (2) Koch Sulfur Products Company, Dubuque, Iowa Fluoride Emissions...

40 CFR 62.1102 - Identification of sources.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Sulfuric Acid Mist Emissions from Existing Sulfuric Acid Production Units § 62.1102 Identification of sources. The plan applies to existing facilities at the following sulfuric acid production units: (a... Chemical Company in Fresno County. (d) Stauffer Chemical Company in Alameda County. (e) Valley Nitrogen...

40 CFR 62.9515 - Identification of sources-Negative declaration.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 8 2010-07-01 2010-07-01 false Identification of sources-Negative declaration. 62.9515 Section 62.9515 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Oregon Metals, Acid Gases, Organic Compounds, Particulates and Nitrogen Oxide Emissions from Existing...

40 CFR 62.10630 - Identification of sources.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Emissions from Commercial and Industrial Solid Waste Incineration (ciswi) Units-Section 111(d)/129 Plan § 62.10630 Identification of sources. The Plan applies to existing Commercial and Industrial Solid Waste Incineration Units that Commenced Construction On or Before November 30, 1999, in Nashville/Davidson County...

40 CFR 62.10630 - Identification of sources.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Emissions from Commercial and Industrial Solid Waste Incineration (ciswi) Units-Section 111(d)/129 Plan § 62.10630 Identification of sources. The Plan applies to existing Commercial and Industrial Solid Waste Incineration Units that Commenced Construction On or Before November 30, 1999, in Nashville/Davidson County...

40 CFR 62.1351 - Identification of sources.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Landfill Gas Emissions from Existing Municipal Solid Waste Landfills § 62.1351 Identification of sources. The plan applies to all existing municipal solid waste landfills for which construction, reconstruction, or modification was commenced before May 30, 1991 that accepted waste at any time since November...

40 CFR 62.5103 - Identification of sources.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Fluoride Emissions from Primary Aluminum Reduction Plants § 62.5103 Identification of sources. (a) The plan applies to the following existing primary aluminum reduction plants: (1) Eastalco Aluminum Plant, Frederick, Maryland. [50 FR 9628, Mar. 11, 1985] Metals, Acid Gases, Organic Compounds and Nitrogen Oxide...

40 CFR 62.5103 - Identification of sources.

Code of Federal Regulations, 2014 CFR

2014-07-01

... Fluoride Emissions from Primary Aluminum Reduction Plants § 62.5103 Identification of sources. (a) The plan applies to the following existing primary aluminum reduction plants: (1) Eastalco Aluminum Plant, Frederick, Maryland. [50 FR 9628, Mar. 11, 1985] Metals, Acid Gases, Organic Compounds and Nitrogen Oxide...

40 CFR 62.5103 - Identification of sources.

Code of Federal Regulations, 2013 CFR

2013-07-01

... Fluoride Emissions from Primary Aluminum Reduction Plants § 62.5103 Identification of sources. (a) The plan applies to the following existing primary aluminum reduction plants: (1) Eastalco Aluminum Plant, Frederick, Maryland. [50 FR 9628, Mar. 11, 1985] Metals, Acid Gases, Organic Compounds and Nitrogen Oxide...

40 CFR 62.5103 - Identification of sources.

Code of Federal Regulations, 2012 CFR

2012-07-01

... Fluoride Emissions from Primary Aluminum Reduction Plants § 62.5103 Identification of sources. (a) The plan applies to the following existing primary aluminum reduction plants: (1) Eastalco Aluminum Plant, Frederick, Maryland. [50 FR 9628, Mar. 11, 1985] Metals, Acid Gases, Organic Compounds and Nitrogen Oxide...

40 CFR 62.107 - Identification of sources.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Emissions from Commercial and Industrial Solid Waste Incineration (ciswi) Units (section 111(d)/129 Plan) § 62.107 Identification of sources. The Plan applies to existing Commercial and Industrial Solid Waste Incineration Units that commenced construction on or before November 30, 1999. [68 FR 4105, Jan. 28, 2003] ...

40 CFR 62.6127 - Identification of Sources.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Emissions from Commercial and Industrial Solid Waste Incineration (ciswi) Units (section 111(d)/129 Plan) § 62.6127 Identification of Sources. The Plan applies to existing Commercial and Industrial Solid Waste Incineration Units that Commenced Construction On or Before November 30, 1999. [68 FR 25293, May 12, 2003] ...

40 CFR 62.6127 - Identification of Sources.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Emissions from Commercial and Industrial Solid Waste Incineration (ciswi) Units (section 111(d)/129 Plan) § 62.6127 Identification of Sources. The Plan applies to existing Commercial and Industrial Solid Waste Incineration Units that Commenced Construction On or Before November 30, 1999. [68 FR 25293, May 12, 2003] ...

40 CFR 62.107 - Identification of sources.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Emissions from Commercial and Industrial Solid Waste Incineration (ciswi) Units (section 111(d)/129 Plan) § 62.107 Identification of sources. The Plan applies to existing Commercial and Industrial Solid Waste Incineration Units that commenced construction on or before November 30, 1999. [68 FR 4105, Jan. 28, 2003] ...

Fast Identification of Methane and Other Atmospheric Contaminant Sources in Complex Urban Settings

NASA Astrophysics Data System (ADS)

Jacobson, G. A.; Crosson, E.; Tan, S. M.

2012-12-01

The identification and quantification of greenhouse gas emissions (fluxes) from urban centers have become of increasing interest over the last few years. This interest is driven by recent measurements indicating that urban emissions are a significant source of methane (CH4) and in fact may be substantially higher than current inventory estimates(1). Urban CH4 emissions could contribute 7-15% to the global anthropogenic budget of methane. Although it is known that the per capita carbon footprint of compact cities, such as New York City, Boston, and San Francisco, are smaller than sprawling cities, such as Houston, the strengths of individual sources within these cities are not well known. Such information is of use to policy makers because it can be used to incentivize changes in transportation and land use patterns. The work discussed here will highlight a vehicle-based methodology for characterizing urban emissions that enables extremely fast identification of methane sources in complex urban settings. Measurements were taken while driving at speeds from 20 to 40 miles per hour in stop and go traffic and were able to not only identify methane plumes but in addition, provide information about the location of the sources generating these methane plumes. Results showed that a large number of highly localized methane sources were found in Boston and San Francisco. For example, leaks from natural gas production, transmission and distribution lines were found in both cities. Flux chamber measurements of these leaks indicate that the methane flux ranged from 40 to 300 standard cubic feet of natural gas per day. For reference, the average American home uses approximately 200-300 cubic feet of natural gas per day. These leaks increase cost to natural gas suppliers, add to greenhouse gas concentrations, and in extreme cases pose a safety hazard. In this work, results showing the identification, location, and quantifying methane sources in urban settings will be presented. We will also present how these techniques could be extended for use in further identification of urban emissions, for example, by measuring H2S produced by sewage, landfills or industrial processes. (1) Wunch, D., P.O. Wennberg, G.C. Toon, G. Keppel-Aleks, and Y.G. Yavin, Emissions of Greenhouse Gases from a North American Megacity, Geophysical Research Letters, Vol. 36, L15810, doi:10.1029/2009GL)39825, 2009.; Mobile methane survey results showing how plume signatures can be used to identify natural gas leaks as a source of methane.

40 CFR 62.2353 - Identification of sources.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Reduced Sulfur Emissions from Kraft Pulp Mills and Tall Oil Plants § 62.2353 Identification of sources. The plan applies to existing facilities at the following existing kraft pulp plants and tall oil... in Panama City (i) Arizona Chemical Company (Tall Oil Plant) in Panama City (j) Sylvachem Corporation...

40 CFR 62.855 - Identification of sources.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Sulfuric Acid Mist Emissions from Existing Sulfuric Acid Plants § 62.855 Identification of sources. (a) The plan applies to existing facilities at the following existing sulfuric acid plant: (1) El Dorado Chemical Company in El Dorado, Arkansas. (2) [Reserved] (b) [Reserved] [63 FR 11608, Mar. 10, 1998] Total...

40 CFR 62.855 - Identification of sources.

Code of Federal Regulations, 2013 CFR

2013-07-01

... Sulfuric Acid Mist Emissions from Existing Sulfuric Acid Plants § 62.855 Identification of sources. (a) The plan applies to existing facilities at the following existing sulfuric acid plant: (1) El Dorado Chemical Company in El Dorado, Arkansas. (2) [Reserved] (b) [Reserved] [63 FR 11608, Mar. 10, 1998] Total...

40 CFR 62.2353 - Identification of sources.

Code of Federal Regulations, 2014 CFR

2014-07-01

... in Panama City (i) Arizona Chemical Company (Tall Oil Plant) in Panama City (j) Sylvachem Corporation... Reduced Sulfur Emissions from Kraft Pulp Mills and Tall Oil Plants § 62.2353 Identification of sources. The plan applies to existing facilities at the following existing kraft pulp plants and tall oil...

40 CFR 62.2353 - Identification of sources.

Code of Federal Regulations, 2012 CFR

2012-07-01

... in Panama City (i) Arizona Chemical Company (Tall Oil Plant) in Panama City (j) Sylvachem Corporation... Reduced Sulfur Emissions from Kraft Pulp Mills and Tall Oil Plants § 62.2353 Identification of sources. The plan applies to existing facilities at the following existing kraft pulp plants and tall oil...

40 CFR 62.855 - Identification of sources.

Code of Federal Regulations, 2014 CFR

2014-07-01

... Sulfuric Acid Mist Emissions from Existing Sulfuric Acid Plants § 62.855 Identification of sources. (a) The plan applies to existing facilities at the following existing sulfuric acid plant: (1) El Dorado Chemical Company in El Dorado, Arkansas. (2) [Reserved] (b) [Reserved] [63 FR 11608, Mar. 10, 1998] Total...

40 CFR 62.855 - Identification of sources.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Sulfuric Acid Mist Emissions from Existing Sulfuric Acid Plants § 62.855 Identification of sources. (a) The plan applies to existing facilities at the following existing sulfuric acid plant: (1) El Dorado Chemical Company in El Dorado, Arkansas. (2) [Reserved] (b) [Reserved] [63 FR 11608, Mar. 10, 1998] Total...

40 CFR 62.855 - Identification of sources.

Code of Federal Regulations, 2012 CFR

2012-07-01

... Sulfuric Acid Mist Emissions from Existing Sulfuric Acid Plants § 62.855 Identification of sources. (a) The plan applies to existing facilities at the following existing sulfuric acid plant: (1) El Dorado Chemical Company in El Dorado, Arkansas. (2) [Reserved] (b) [Reserved] [63 FR 11608, Mar. 10, 1998] Total...

40 CFR 62.2353 - Identification of sources.

Code of Federal Regulations, 2013 CFR

2013-07-01

... in Panama City (i) Arizona Chemical Company (Tall Oil Plant) in Panama City (j) Sylvachem Corporation... Reduced Sulfur Emissions from Kraft Pulp Mills and Tall Oil Plants § 62.2353 Identification of sources. The plan applies to existing facilities at the following existing kraft pulp plants and tall oil...

40 CFR 62.2380 - Identification of sources.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Emissions from Commercial and Industrial Solid Waste Incineration (ciswi) Units (section 111(d)/129 Plan) § 62.2380 Identification of sources. The Plan applies to existing Commercial and Industrial Solid Waste Incineration Units that Commenced Construction On or Before November 30, 1999. [68 FR 17885, Apr. 14, 2003] Air...

40 CFR 62.2380 - Identification of sources.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Emissions from Commercial and Industrial Solid Waste Incineration (ciswi) Units (section 111(d)/129 Plan) § 62.2380 Identification of sources. The Plan applies to existing Commercial and Industrial Solid Waste Incineration Units that Commenced Construction On or Before November 30, 1999. [68 FR 17885, Apr. 14, 2003] Air...

Atmospheric aerosol source identification and estimates of source contributions to air pollution in Dundee, UK

NASA Astrophysics Data System (ADS)

Qin, Y.; Oduyemi, K.

Anthropogenic aerosol (PM 10) emission sources sampled at an air quality monitoring station in Dundee have been analysed. However, the information on local natural aerosol emission sources was unavailable. A method that combines receptor model and atmospheric dispersion model was used to identify aerosol sources and estimate source contributions to air pollution. The receptor model identified five sources. These are aged marine aerosol source with some chlorine replaced by sulphate, secondary aerosol source of ammonium sulphate, secondary aerosol source of ammonium nitrate, soil and construction dust source, and incinerator and fuel oil burning emission source. For the vehicle emission source, which has been comprehensively described in the atmospheric emission inventory but cannot be identified by the receptor model, an atmospheric dispersion model was used to estimate its contributions. In Dundee, a significant percentage, 67.5%, of the aerosol mass sampled at the study station could be attributed to the six sources named above.

40 CFR 62.2602 - Identification of sources-negative declaration.

Code of Federal Regulations, 2014 CFR

2014-07-01

... Georgia Fluoride Emissions from Phosphate Fertilizer Plants § 62.2602 Identification of sources—negative... that there are no existing phosphate fertilizer plants in the State subject to part 60, subpart B, of...

40 CFR 62.2602 - Identification of sources-negative declaration.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Georgia Fluoride Emissions from Phosphate Fertilizer Plants § 62.2602 Identification of sources—negative... that there are no existing phosphate fertilizer plants in the State subject to part 60, subpart B, of...

40 CFR 62.2602 - Identification of sources-negative declaration.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Georgia Fluoride Emissions from Phosphate Fertilizer Plants § 62.2602 Identification of sources—negative... that there are no existing phosphate fertilizer plants in the State subject to part 60, subpart B, of...

40 CFR 62.3300 - Identification of plan.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Mist Emissions from Existing Sulfuric Acid Production Plants § 62.3300 Identification of plan. (a... Sulfuric Acid Plants.” (b) The plan was officially submitted on August 10, 1978. (c) Identification of sources: The plan includes the following sulfuric acid production plants: (1) Beker Industries in LaSalle...

40 CFR 62.3300 - Identification of plan.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Mist Emissions from Existing Sulfuric Acid Production Plants § 62.3300 Identification of plan. (a... Sulfuric Acid Plants.” (b) The plan was officially submitted on August 10, 1978. (c) Identification of sources: The plan includes the following sulfuric acid production plants: (1) Beker Industries in LaSalle...

40 CFR 62.3300 - Identification of plan.

Code of Federal Regulations, 2013 CFR

2013-07-01

... Mist Emissions from Existing Sulfuric Acid Production Plants § 62.3300 Identification of plan. (a... Sulfuric Acid Plants.” (b) The plan was officially submitted on August 10, 1978. (c) Identification of sources: The plan includes the following sulfuric acid production plants: (1) Beker Industries in LaSalle...

40 CFR 62.3300 - Identification of plan.

Code of Federal Regulations, 2012 CFR

2012-07-01

... Mist Emissions from Existing Sulfuric Acid Production Plants § 62.3300 Identification of plan. (a... Sulfuric Acid Plants.” (b) The plan was officially submitted on August 10, 1978. (c) Identification of sources: The plan includes the following sulfuric acid production plants: (1) Beker Industries in LaSalle...

40 CFR 62.3300 - Identification of plan.

Code of Federal Regulations, 2014 CFR

2014-07-01

... Mist Emissions from Existing Sulfuric Acid Production Plants § 62.3300 Identification of plan. (a... Sulfuric Acid Plants.” (b) The plan was officially submitted on August 10, 1978. (c) Identification of sources: The plan includes the following sulfuric acid production plants: (1) Beker Industries in LaSalle...

40 CFR 62.11610 - Identification of plan.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Reduced Sulfur Emissions from Existing Kraft Pulp Mills § 62.11610 Identification of plan. (a) Title of... Department of Virginia Department of Air Pollution Control, on May 15, 1990. (c) Identification of sources... process (added), Straight kraft recovery furnace (revised), Total reduced sulfur (revised)), 5-40-1690, 5...

40 CFR 62.8104 - Identification of plan.

Code of Federal Regulations, 2010 CFR

2010-07-01

...) APPROVAL AND PROMULGATION OF STATE PLANS FOR DESIGNATED FACILITIES AND POLLUTANTS New York Landfill Gas Emissions from Existing Municipal Solid Waste Landfills § 62.8104 Identification of plan. (a) The New York... Municipal Solid Waste Landfills” on October 8, 1998. (b) Identification of sources: The plan applies to all...

40 CFR 62.8102 - Identification of plan.

Code of Federal Regulations, 2013 CFR

2013-07-01

... Mist Emissions from Existing Sulfuric Acid Plants § 62.8102 Identification of plan. (a) [Reserved] (b... Plants” of Title 6 of the New York Code of Rules and Regulations effective May 10, 1984. (2) Supplemental information submitted on March 29, 1985. (c) Identification of sources. The plan includes the following plants...

40 CFR 62.8102 - Identification of plan.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Mist Emissions from Existing Sulfuric Acid Plants § 62.8102 Identification of plan. (a) [Reserved] (b... Plants” of Title 6 of the New York Code of Rules and Regulations effective May 10, 1984. (2) Supplemental information submitted on March 29, 1985. (c) Identification of sources. The plan includes the following plants...

40 CFR 62.8102 - Identification of plan.

Code of Federal Regulations, 2012 CFR

2012-07-01

... Mist Emissions from Existing Sulfuric Acid Plants § 62.8102 Identification of plan. (a) [Reserved] (b... Plants” of Title 6 of the New York Code of Rules and Regulations effective May 10, 1984. (2) Supplemental information submitted on March 29, 1985. (c) Identification of sources. The plan includes the following plants...

40 CFR 62.8102 - Identification of plan.

Code of Federal Regulations, 2014 CFR

2014-07-01

... Mist Emissions from Existing Sulfuric Acid Plants § 62.8102 Identification of plan. (a) [Reserved] (b... Plants” of Title 6 of the New York Code of Rules and Regulations effective May 10, 1984. (2) Supplemental information submitted on March 29, 1985. (c) Identification of sources. The plan includes the following plants...

Spectral Models of Neutron Star Magnetospheres

NASA Technical Reports Server (NTRS)

Romani, Roger W.

1997-01-01

We revisit the association of unidentified Galactic plane EGRET sources with tracers of recent massive star formation and death. Up-to-date catalogs of OB associations, SNR's, young pulsars, H2 regions and young open clusters were used in finding counterparts for a recent list of EGRET sources. It has been argued for some time that EGRET source positions are correlated with SNR's and OB associations as a class; we extend such analyses by finding additional counterparts and assessing the probability of individual source identifications. Among the several scenarios relating EGRET sources to massive stars, we focus on young neutron stars as the origin of the gamma-ray emission. The characteristics of the candidate identifications are compared to the known gamma-ray pulsar sample and to detailed Galactic population syntheses using our outer gap pulsar model of gamma-ray emission. Both the spatial distribution and luminosity function of the candidates are in good agreement with the model predictions; we infer that young pulsars can account for the bulk of the excess low latitude EGRET sources. We show that with this identification, the gamma-ray point sources provide an important new window into the history of recent massive star death in the solar neighborhood.

First measurements of a carbon dioxide plume from an industrial source using a ground based mobile differential absorption lidar.

PubMed

Robinson, R A; Gardiner, T D; Innocenti, F; Finlayson, A; Woods, P T; Few, J F M

2014-08-01

The emission of carbon dioxide (CO2) from industrial sources is one of the main anthropogenic contributors to the greenhouse effect. Direct remote sensing of CO2 emissions using optical methods offers the potential for the identification and quantification of CO2 emissions. We report the development and demonstration of a ground based mobile differential absorption lidar (DIAL) able to measure the mass emission rate of CO2 in the plume from a power station. To our knowledge DIAL has not previously been successfully applied to the measurement of emission plumes of CO2 from industrial sources. A significant challenge in observing industrial CO2 emission plumes is the ability to discriminate and observe localised concentrations of CO2 above the locally observed background level. The objectives of the study were to modify our existing mobile infrared DIAL system to enable CO2 measurements and to demonstrate the system at a power plant to assess the feasibility of the technique for the identification and quantification of CO2 emissions. The results of this preliminary study showed very good agreement with the expected emissions calculated by the site. The detection limit obtained from the measurements, however, requires further improvement to provide quantification of smaller emitters of CO2, for example for the detection of fugitive emissions. This study has shown that in principle, remote optical sensing technology will have the potential to provide useful direct data on CO2 mass emission rates.

IDENTIFICATION AND CHARACTERIZATION OF MISSING AND UNACCOUNTED FOR AREA SOURCE CATEGORIES

EPA Science Inventory

The report identifies and characterizes missing or unaccounted for area source categories. Area source emissions of particulate matter (TSP), sulfur dioxide (SO2), oxides of nitrogen (NOx), reactive volatile organic compounds (VOCs), and carbon monoxide (CO) are estimated annuall...

40 CFR 62.13106 - Identification of plan.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Control of Air Emissions of Designated Pollutants from Existing Hospital, Medical, and Infectious Waste.../Infectious Waste Incinerators. (b) Identification of sources: The plan applies to all applicable existing hospital/medical/infectious waste incinerators for which construction commenced on or before June 20, 1996...

40 CFR 62.10190 - Identification of Sources.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Air Emissions from Commercial and Industrial Solid Waste Incineration (ciswi) Units (section 111(d... Solid Waste Incineration Units that Commenced Construction On or Before November 30, 1999. [69 FR 9557, Mar. 1, 2004] Air Emissions From Existing Hospital/Medical/Infectious Waste Incinerators (HMIWI...

Identification and preliminary evaluation of polychlorinated naphthalene emissions from hot dip galvanizing plants.

PubMed

Liu, Guorui; Lv, Pu; Jiang, Xiaoxu; Nie, Zhiqiang; Liu, Wenbin; Zheng, Minghui

2015-01-01

Hot dip galvanizing (HDG) processes are sources of polychlorinated-p-dioxins and dibenzofurans (PCDD/Fs). Close correlations have been found between the concentration of PCDD/Fs and polychlorinated naphthalenes (PCNs) that are produced and released during industrial thermal processes. We speculated, therefore, that HDG plants are potential PCN sources. In this preliminary study, PCNs were analyzed in solid residues, ash and precipitate from three HDG plants of different sizes. The total PCN concentrations (∑2-8PCNs) in the residue samples ranged from 60.3 to 226pgg(-1). The PCN emission factors for the combined ash and precipitate residues from the HDG plants ranged from 75 to 178ngt(-1) for the dichlorinated and octachlorinated naphthalenes. The preliminary results suggested that the HDG industry might not currently be a significant source of PCN emissions. The trichloronaphthalenes were the dominant homologs followed by the dichloronaphthalenes and the tetrachloronaphthalenes. The PCN congeners CN37/33/34, CN52/60, CN66/67, and CN73 dominated the tetrachlorinated, pentachlorinated, hexachlorinated, and heptachlorinated naphthalene homologs, respectively. The PCNs emitted from the HDG plants had similar homolog distributions and congener profiles to the PCNs emitted from combustion plants and other metallurgical processes. The identification and preliminary evaluation of PCN emissions from HDG plants presented here will help in the prioritization of measures for controlling PCN emissions from industrial sources. Copyright © 2014 Elsevier Ltd. All rights reserved.

A portable neutron spectroscope (NSPECT) for detection, imaging and identification of nuclear material

NASA Astrophysics Data System (ADS)

Ryan, James M.; Bancroft, Christopher; Bloser, Peter; Bravar, Ulisse; Fourguette, Dominique; Frost, Colin; Larocque, Liane; McConnell, Mark L.; Legere, Jason; Pavlich, Jane; Ritter, Greg; Wassick, Greg; Wood, Joshua; Woolf, Richard

2010-08-01

We have developed, fabricated and tested a prototype imaging neutron spectrometer designed for real-time neutron source location and identification. Real-time detection and identification is important for locating materials. These materials, specifically uranium and transuranics, emit neutrons via spontaneous or induced fission. Unlike other forms of radiation (e.g. gamma rays), penetrating neutron emission is very uncommon. The instrument detects these neutrons, constructs images of the emission pattern, and reports the neutron spectrum. The device will be useful for security and proliferation deterrence, as well as for nuclear waste characterization and monitoring. The instrument is optimized for imaging and spectroscopy in the 1-20 MeV range. The detection principle is based upon multiple elastic neutron-proton scatters in organic scintillator. Two detector panel layers are utilized. By measuring the recoil proton and scattered neutron locations and energies, the direction and energy spectrum of the incident neutrons can be determined and discrete and extended sources identified. Event reconstruction yields an image of the source and its location. The hardware is low power, low mass, and rugged. Its modular design allows the user to combine multiple units for increased sensitivity. We will report the results of laboratory testing of the instrument, including exposure to a calibrated Cf-252 source. Instrument parameters include energy and angular resolution, gamma rejection, minimum source identification distances and times, and projected effective area for a fully populated instrument.

75 FR 32682 - National Emission Standards for Hazardous Air Pollutants for Major Sources: Industrial...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-06-09

... for Existing Sources: Commercial and Industrial Solid Waste Incineration Units; Identification of Non-Hazardous Secondary Materials That Are Solid Waste AGENCY: Environmental Protection Agency. ACTION: Notice... Institutional Boilers located at area sources; and Commercial and Industrial Solid Waste Incineration Units. On...

40 CFR 62.7860 - Identification of sources-negative declaration.

Code of Federal Regulations, 2013 CFR

2013-07-01

... Mexico Emissions from Existing Large Municipal Waste Combustion Units § 62.7860 Identification of sources—negative declaration. Letter from the City of Albuquerque Air Pollution Control Division dated September 10... declaration. 62.7860 Section 62.7860 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR...

40 CFR 62.7860 - Identification of sources-negative declaration.

Code of Federal Regulations, 2012 CFR

2012-07-01

... Mexico Emissions from Existing Large Municipal Waste Combustion Units § 62.7860 Identification of sources—negative declaration. Letter from the City of Albuquerque Air Pollution Control Division dated September 10... declaration. 62.7860 Section 62.7860 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR...

40 CFR 62.7860 - Identification of sources-negative declaration.

Code of Federal Regulations, 2014 CFR

2014-07-01

... Mexico Emissions from Existing Large Municipal Waste Combustion Units § 62.7860 Identification of sources—negative declaration. Letter from the City of Albuquerque Air Pollution Control Division dated September 10... declaration. 62.7860 Section 62.7860 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR...

Source identification and apportionment of halogenated compounds observed at a remote site in East Asia.

PubMed

Li, Shanlan; Kim, Jooil; Park, Sunyoung; Kim, Seung-Kyu; Park, Mi-Kyung; Mühle, Jens; Lee, Gangwoong; Lee, Meehye; Jo, Chun Ok; Kim, Kyung-Ryul

2014-01-01

The sources of halogenated compounds in East Asia associated with stratospheric ozone depletion and climate change are relatively poorly understood. High-precision in situ measurements of 18 halogenated compounds and carbonyl sulfide (COS) made at Gosan, Jeju Island, Korea, from November 2007 to December 2011 were analyzed by a positive matrix factorization (PMF). Seven major industrial sources were identified from the enhanced concentrations of halogenated compounds observed at Gosan and corresponding concentration-based source contributions were also suggested: primary aluminum production explaining 37% of total concentration enhancements, solvent usage of which source apportionment is 25%, fugitive emissions from HCFC/HFC production with 11%, refrigerant replacements (9%), semiconductor/electronics industry (9%), foam blowing agents (6%), and fumigation (3%). Statistical trajectory analysis was applied to specify the potential emission regions for seven sources using back trajectories. Primary aluminum production, solvent usage and fugitive emission sources were mainly contributed by China. Semiconductor/electronics sources were dominantly located in Korea. Refrigerant replacement, fumigation and foam blowing agent sources were spread throughout East Asian countries. The specified potential source regions are consistent with country-based consumptions and emission patterns, verifying the PMF analysis results. The industry-based emission sources of halogenated compounds identified in this study help improve our understanding of the East Asian countries' industrial contributions to halogenated compound emissions.

40 CFR 62.8355 - Identification of sources.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Air Emissions from Commercial and Industrial Solid Waste Incineration (ciswi) Units-Section 111(d)/129... Waste Incineration Units that Commenced Construction On or Before November 30, 1999. [70 FR 56856, Sept. 29, 2005] Air Emissions From Existing Hospital/Medical/Infectious Waste Incinerators (HMIWI)—Section...

40 CFR 62.8355 - Identification of sources.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Air Emissions from Commercial and Industrial Solid Waste Incineration (ciswi) Units-Section 111(d)/129... Waste Incineration Units that Commenced Construction On or Before November 30, 1999. [70 FR 56856, Sept. 29, 2005] Air Emissions From Existing Hospital/Medical/Infectious Waste Incinerators (HMIWI)—Section...

Identification of tropospheric emissions sources from satellite observations: Synergistic use of HCHO, NO2, and SO2 trace gas measurements

NASA Astrophysics Data System (ADS)

Marbach, T.; Beirle, S.; Khokhar, F.; Platt, U.

2005-12-01

We present case studies for combined HCHO, NO2, and SO2 satellite observations, derived from GOME measurements. Launched on the ERS-2 satellite in April 1995, GOME has already performed continuous operations over 8 years providing global observations of the different trace gases. In this way, satellite observations provide unique opportunities for the identifications of trace gas sources. The satellite HCHO observations provide information concerning the localization of biomass burning (intense source of HCHO). The principal biomass burning areas can be observed in the Amazon basin region and in central Africa Weaker HCHO sources (south east of the United States, northern part of the Amazon basin, and over the African tropical forest), not correlated with biomass burning, could be due to biogenic isoprene emissions. The HCHO data can be compared with NO2 and SO2 results to identify more precisely the tropospheric sources (biomass burning events, human activities, additional sources like volcanic emissions). Biomass burning are important tropospheric sources for both HCHO and NO2. Nevertheless HCHO reflects more precisely the biomass burning as it appears in all biomass burning events. NO2 correlate with HCHO over Africa (grassland fires) but not over Indonesia (forest fires). In south America, an augmentation of the NO2 concentrations can be observed with the fire shift from the forest to grassland vegetation. So there seems to be a dependence between the NO2 emissions during biomass burning and the vegetation type. Other high HCHO, SO2, and NO2 emissions can be correlated with climatic events like the El Nino in 1997, which induced dry conditions in Indonesia causing many forest fires.

Identifying key sources of uncertainty in the modelling of greenhouse gas emissions from wastewater treatment.

PubMed

Sweetapple, Christine; Fu, Guangtao; Butler, David

2013-09-01

This study investigates sources of uncertainty in the modelling of greenhouse gas emissions from wastewater treatment, through the use of local and global sensitivity analysis tools, and contributes to an in-depth understanding of wastewater treatment modelling by revealing critical parameters and parameter interactions. One-factor-at-a-time sensitivity analysis is used to screen model parameters and identify those with significant individual effects on three performance indicators: total greenhouse gas emissions, effluent quality and operational cost. Sobol's method enables identification of parameters with significant higher order effects and of particular parameter pairs to which model outputs are sensitive. Use of a variance-based global sensitivity analysis tool to investigate parameter interactions enables identification of important parameters not revealed in one-factor-at-a-time sensitivity analysis. These interaction effects have not been considered in previous studies and thus provide a better understanding wastewater treatment plant model characterisation. It was found that uncertainty in modelled nitrous oxide emissions is the primary contributor to uncertainty in total greenhouse gas emissions, due largely to the interaction effects of three nitrogen conversion modelling parameters. The higher order effects of these parameters are also shown to be a key source of uncertainty in effluent quality. Copyright © 2013 Elsevier Ltd. All rights reserved.

Direct Quantification of Methane Emissions Across the Supply Chain: Identification of Mitigation Targets

NASA Astrophysics Data System (ADS)

Darzi, M.; Johnson, D.; Heltzel, R.; Clark, N.

2017-12-01

Researchers at West Virginia University's Center for Alternative Fuels, Engines, and Emissions have recently participated in a variety of studies targeted at direction quantification of methane emissions from across the natural gas supply chain. These studies included assessing methane emissions from heavy-duty vehicles and their fuel stations, active unconventional well sites - during both development and production, natural gas compression and storage facilities, natural gas engines - both large and small, two- and four-stroke, and low-throughput equipment associated with coal bed methane wells. Engine emissions were sampled using conventional instruments such as Fourier transform infrared spectrometers and heated flame ionization detection analyzers. However, to accurately quantify a wide range of other sources beyond the tailpipe (both leaks and losses), a full flow sampling system was developed, which included an integrated cavity-enhanced absorption spectrometer. Through these direct quantification efforts and analysis major sources of methane emissions were identified. Technological solutions and best practices exist or could be developed to reduce methane emissions by focusing on the "lowest-hanging fruit." For example, engine crankcases from across the supply chain should employ vent mitigation systems to reduce methane and other emissions. An overview of the direct quantification system and various campaign measurements results will be presented along with the identification of other targets for additional mitigation.

X-ray emission from the Pleiades cluster

NASA Technical Reports Server (NTRS)

Agrawal, P. C.; Singh, K. P.; Riegler, G. R.

1983-01-01

The detection and identification of H0344+24, a new X-ray source located in the Pleiades cluster, is reported, based on observations made with HEAO A-2 low-energy detector 1 in the 0.15-3.0-keV energy band in August, 1977. The 90-percent-confidence error box for the new source is centered at 03 h 44.1 min right ascension (1950), near the center star of the 500-star Pleiades cluster, 25-eta-Tau. Since no likely galactic or extragalactic source of X-rays was found in a catalog search of the error-box region, identification of the source with the Pleiades cluster is considered secure. X-ray luminosity of the source is calculated to be about 10 to the 32nd ergs/sec, based on a distance of 125 pc. The X-ray characteristics of the Pleiades stars are discussed, and it is concluded that H0344+24 can best be explained as the integrated X-ray emission of all the B and F stars in the cluster.

40 CFR 63.53 - Application content for case-by-case MACT determinations.

Code of Federal Regulations, 2012 CFR

2012-07-01

... identified emission point or group of affected emission points, an identification of control technology in... on the design, operation, size, estimated control efficiency and any other information deemed... CATEGORIES Requirements for Control Technology Determinations for Major Sources in Accordance With Clean Air...

40 CFR 63.53 - Application content for case-by-case MACT determinations.

Code of Federal Regulations, 2014 CFR

2014-07-01

... identified emission point or group of affected emission points, an identification of control technology in... on the design, operation, size, estimated control efficiency and any other information deemed... CATEGORIES Requirements for Control Technology Determinations for Major Sources in Accordance With Clean Air...

40 CFR 63.53 - Application content for case-by-case MACT determinations.

Code of Federal Regulations, 2013 CFR

2013-07-01

... identified emission point or group of affected emission points, an identification of control technology in... on the design, operation, size, estimated control efficiency and any other information deemed... CATEGORIES Requirements for Control Technology Determinations for Major Sources in Accordance With Clean Air...

40 CFR 63.53 - Application content for case-by-case MACT determinations.

Code of Federal Regulations, 2011 CFR

2011-07-01

... identified emission point or group of affected emission points, an identification of control technology in... on the design, operation, size, estimated control efficiency and any other information deemed... CATEGORIES Requirements for Control Technology Determinations for Major Sources in Accordance With Clean Air...

40 CFR 63.53 - Application content for case-by-case MACT determinations.

Code of Federal Regulations, 2010 CFR

2010-07-01

... MACT determinations. 63.53 Section 63.53 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY... CATEGORIES Requirements for Control Technology Determinations for Major Sources in Accordance With Clean Air... identified emission point or group of affected emission points, an identification of control technology in...

Acoustic emission based damage localization in composites structures using Bayesian identification

NASA Astrophysics Data System (ADS)

Kundu, A.; Eaton, M. J.; Al-Jumali, S.; Sikdar, S.; Pullin, R.

2017-05-01

Acoustic emission based damage detection in composite structures is based on detection of ultra high frequency packets of acoustic waves emitted from damage sources (such as fibre breakage, fatigue fracture, amongst others) with a network of distributed sensors. This non-destructive monitoring scheme requires solving an inverse problem where the measured signals are linked back to the location of the source. This in turn enables rapid deployment of mitigative measures. The presence of significant amount of uncertainty associated with the operating conditions and measurements makes the problem of damage identification quite challenging. The uncertainties stem from the fact that the measured signals are affected by the irregular geometries, manufacturing imprecision, imperfect boundary conditions, existing damages/structural degradation, amongst others. This work aims to tackle these uncertainties within a framework of automated probabilistic damage detection. The method trains a probabilistic model of the parametrized input and output model of the acoustic emission system with experimental data to give probabilistic descriptors of damage locations. A response surface modelling the acoustic emission as a function of parametrized damage signals collected from sensors would be calibrated with a training dataset using Bayesian inference. This is used to deduce damage locations in the online monitoring phase. During online monitoring, the spatially correlated time data is utilized in conjunction with the calibrated acoustic emissions model to infer the probabilistic description of the acoustic emission source within a hierarchical Bayesian inference framework. The methodology is tested on a composite structure consisting of carbon fibre panel with stiffeners and damage source behaviour has been experimentally simulated using standard H-N sources. The methodology presented in this study would be applicable in the current form to structural damage detection under varying operational loads and would be investigated in future studies.

Identifiability and identification of trace continuous pollutant source.

PubMed

Qu, Hongquan; Liu, Shouwen; Pang, Liping; Hu, Tao

2014-01-01

Accidental pollution events often threaten people's health and lives, and a pollutant source is very necessary so that prompt remedial actions can be taken. In this paper, a trace continuous pollutant source identification method is developed to identify a sudden continuous emission pollutant source in an enclosed space. The location probability model is set up firstly, and then the identification method is realized by searching a global optimal objective value of the location probability. In order to discuss the identifiability performance of the presented method, a conception of a synergy degree of velocity fields is presented in order to quantitatively analyze the impact of velocity field on the identification performance. Based on this conception, some simulation cases were conducted. The application conditions of this method are obtained according to the simulation studies. In order to verify the presented method, we designed an experiment and identified an unknown source appearing in the experimental space. The result showed that the method can identify a sudden trace continuous source when the studied situation satisfies the application conditions.

40 CFR 62.3918 - Identification of plan.

Code of Federal Regulations, 2010 CFR

2010-07-01

...) APPROVAL AND PROMULGATION OF STATE PLANS FOR DESIGNATED FACILITIES AND POLLUTANTS Iowa Mercury Emissions...) Identification of sources. The plan applies to all new and existing mercury budget units meeting the... portion of the plan applicable to mercury budget units as described in Iowa State rule 567-34.301 is...

40 CFR 62.3918 - Identification of plan.

Code of Federal Regulations, 2011 CFR

2011-07-01

...) APPROVAL AND PROMULGATION OF STATE PLANS FOR DESIGNATED FACILITIES AND POLLUTANTS Iowa Mercury Emissions...) Identification of sources. The plan applies to all new and existing mercury budget units meeting the... portion of the plan applicable to mercury budget units as described in Iowa State rule 567-34.301 is...

40 CFR 62.3918 - Identification of plan.

Code of Federal Regulations, 2012 CFR

2012-07-01

...) APPROVAL AND PROMULGATION OF STATE PLANS FOR DESIGNATED FACILITIES AND POLLUTANTS Iowa Mercury Emissions...) Identification of sources. The plan applies to all new and existing mercury budget units meeting the... portion of the plan applicable to mercury budget units as described in Iowa State rule 567-34.301 is...

40 CFR 62.3918 - Identification of plan.

Code of Federal Regulations, 2013 CFR

2013-07-01

...) APPROVAL AND PROMULGATION OF STATE PLANS FOR DESIGNATED FACILITIES AND POLLUTANTS Iowa Mercury Emissions...) Identification of sources. The plan applies to all new and existing mercury budget units meeting the... portion of the plan applicable to mercury budget units as described in Iowa State rule 567-34.301 is...

40 CFR 62.3918 - Identification of plan.

Code of Federal Regulations, 2014 CFR

2014-07-01

...) APPROVAL AND PROMULGATION OF STATE PLANS FOR DESIGNATED FACILITIES AND POLLUTANTS Iowa Mercury Emissions...) Identification of sources. The plan applies to all new and existing mercury budget units meeting the... portion of the plan applicable to mercury budget units as described in Iowa State rule 567-34.301 is...

40 CFR 62.7890 - Identification of sources-negative declarations.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Mexico Emissions from Existing Commercial and Industrial Solid Waste Incineration (ciswi) Units § 62.7890 Identification of sources—negative declarations. (a) Letter from the New Mexico Environment Department dated... subject to 40 CFR part 60, subpart DDDD under its jurisdiction in the State of New Mexico (excluding...

40 CFR 62.7890 - Identification of sources-negative declarations.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Mexico Emissions from Existing Commercial and Industrial Solid Waste Incineration (ciswi) Units § 62.7890 Identification of sources—negative declarations. (a) Letter from the New Mexico Environment Department dated... subject to 40 CFR part 60, subpart DDDD under its jurisdiction in the State of New Mexico (excluding...

40 CFR 62.2350 - Identification of plan.

Code of Federal Regulations, 2013 CFR

2013-07-01

...) emissions from existing kraft pulp mills and tall oil plants (both new and existing) submitted on May 24... is June 1, 1990. (5) Control of metals, acid gases, organic compounds and nitrogen oxide emissions... existing facilities in the following categories of sources: (1) Sulfuric acid plants. (2) Kraft pulp mills...

40 CFR 62.2350 - Identification of plan.

Code of Federal Regulations, 2011 CFR

2011-07-01

...) emissions from existing kraft pulp mills and tall oil plants (both new and existing) submitted on May 24... is June 1, 1990. (5) Control of metals, acid gases, organic compounds and nitrogen oxide emissions... existing facilities in the following categories of sources: (1) Sulfuric acid plants. (2) Kraft pulp mills...

40 CFR 62.2350 - Identification of plan.

Code of Federal Regulations, 2012 CFR

2012-07-01

...) emissions from existing kraft pulp mills and tall oil plants (both new and existing) submitted on May 24... is June 1, 1990. (5) Control of metals, acid gases, organic compounds and nitrogen oxide emissions... existing facilities in the following categories of sources: (1) Sulfuric acid plants. (2) Kraft pulp mills...

40 CFR 62.2350 - Identification of plan.

Code of Federal Regulations, 2014 CFR

2014-07-01

...) emissions from existing kraft pulp mills and tall oil plants (both new and existing) submitted on May 24... is June 1, 1990. (5) Control of metals, acid gases, organic compounds and nitrogen oxide emissions... existing facilities in the following categories of sources: (1) Sulfuric acid plants. (2) Kraft pulp mills...

40 CFR 62.101 - Identification of sources.

Code of Federal Regulations, 2012 CFR

2012-07-01

...) Reichhold Chemical Company in Tuscaloosa, (2) Stauffer Chemical Company in Mobile, and (3) Estech Chemical... bound sulfur feedstock plants. Fluoride Emissions From Phosphate Fertilizer Plants ...

40 CFR 62.101 - Identification of sources.

Code of Federal Regulations, 2013 CFR

2013-07-01

...) Reichhold Chemical Company in Tuscaloosa, (2) Stauffer Chemical Company in Mobile, and (3) Estech Chemical... bound sulfur feedstock plants. Fluoride Emissions From Phosphate Fertilizer Plants ...

40 CFR 62.101 - Identification of sources.

Code of Federal Regulations, 2011 CFR

2011-07-01

...) Reichhold Chemical Company in Tuscaloosa, (2) Stauffer Chemical Company in Mobile, and (3) Estech Chemical... bound sulfur feedstock plants. Fluoride Emissions From Phosphate Fertilizer Plants ...

40 CFR 62.101 - Identification of sources.

Code of Federal Regulations, 2010 CFR

2010-07-01

...) Reichhold Chemical Company in Tuscaloosa, (2) Stauffer Chemical Company in Mobile, and (3) Estech Chemical... bound sulfur feedstock plants. Fluoride Emissions From Phosphate Fertilizer Plants ...

40 CFR 62.101 - Identification of sources.

Code of Federal Regulations, 2014 CFR

2014-07-01

...) Reichhold Chemical Company in Tuscaloosa, (2) Stauffer Chemical Company in Mobile, and (3) Estech Chemical... bound sulfur feedstock plants. Fluoride Emissions From Phosphate Fertilizer Plants ...

Development of emissions inventory and identification of sources for priority control in the middle reaches of Yangtze River Urban Agglomerations.

PubMed

Sun, Xiaowei; Cheng, Shuiyuan; Lang, Jianlei; Ren, Zhenhai; Sun, Chao

2018-06-01

This paper presents the first attempt to investigate the emission source control of the Middle Reaches of Yangtze River Urban Agglomerations (MRYRUA), one of the national urban agglomerations in China. An emission inventory of the MRYRUA was developed as inputs to the CAMx model based on county-level activity data obtained by full-coverage investigation and source-based spatial surrogates. A classification technology method for priority control of atmospheric emission sources was introduced and applied in the MRYRUA for the evaluation of the emission sources control on the region-scale and city-scale, respectively. The results demonstrated that the emission sources in the Hefei-centered urban agglomerations contributed the biggest on the mean PM 2.5 concentrations of the MRYRUA and should be taken the priority to control. The emission sources in the Ma'anshan city, Xiangtan city, Hefei city and Wuhan city were the bigger contributors on the mean PM 2.5 concentrations of the MRYRUA among the cities and should be taken the priority to control. In generally, emission sources in cities along the Yangtze River and the tributary should be given the special attention for the regional air quality target attainments. This study can give an understanding of Chinese emissions and provide a valuable preference to policy makers for finding effective mitigation measures and control strategies for reducing national and regional air pollution in China. Copyright © 2017 Elsevier B.V. All rights reserved.

IDENTIFICATION AND CHARACTERIZATION OF FIVE NON- TRADITIONAL SOURCE CATEGORIES: CATASTROPHIC/ACCIDENTAL RELEASES, VEHICLE REPAIR FACILITIES, RECYCLING, PESTICIDE APPLICATION, AND AGRICULTURAL OPERATIONS

EPA Science Inventory

The report gives results of work that is part of EPA's program to identify and characterize emissions sources not currently accounted for by either the existing Aerometric Information Retrieval System (AIRS) or State Implementation Plan (SIP) area source methodologies and to deve...

Spatial distribution and source identification of indicator polychlorinated biphenyls in soil collected from the coastal multi-industrial city of Ulsan, South Korea for three consecutive years.

PubMed

Nguyen, Tuyet Nam Thi; Kwon, Hye-Ok; Lee, Yun-Se; Kim, Leesun; Lee, Sung-Eun; Choi, Sung-Deuk

2016-11-01

The concentrations, profiles, and source-receptor relationships of seven indicator polychlorinated biphenyls (PCBs) (#28, 52, 101, 118, 138, 153, and 180) found in soil at 25 rural, urban, and industrial sites in Ulsan, South Korea were investigated. For this study, 75 soil samples were collected, 25 each in January of 2011, 2012, and 2013. Principal component analysis was used to evaluate the influence of the emission sources on the soil samples. The concentrations of total seven PCBs (Σ7 PCBs) ranged between 0.034 ng/g and 143 ng/g (mean: 5.10 ng/g, median: 0.440 ng/g), which indicated slight or moderate contamination levels, respectively, compared to those in the other countries or other cities in Korea. The concentrations of Σ7 PCBs at the industrial and urban sites were significantly higher than those at the rural sites, due to the direct influence of emission sources related to industrial activities rather than urban emission sources. Generally, the profiles of PCBs were dominated by penta- and hexa-chlorinated biphenyls at all the study sites, suggesting common sources of PCBs in Ulsan. PCB source identification indicated that leakage from transformer oils in the major industrial complexes and PCB-containing paints used in the automobile and shipbuilding industrial complexes were possibly the main sources of indicator PCBs in the study areas. Copyright © 2016 Elsevier Ltd. All rights reserved.

Mobile laboratory measurements of atmospheric emissions from agriculture, oil, and natural gas activities in northeastern Colorado

NASA Astrophysics Data System (ADS)

Eilerman, S. J.; Peischl, J.; Neuman, J. A.; Ryerson, T. B.; Wild, R. J.; Perring, A. E.; Brown, S. S.; Aikin, K. C.; Holloway, M.; Roberts, O.

2014-12-01

Atmospheric emissions from agriculture are important to air quality and climate, yet their representation in inventories is incomplete. Increased fertilizer use has lead to increased emissions of nitrogen compounds, which can adversely affect ecosystems and contribute to the formation of fine particulates. Furthermore, extraction and processing of oil and natural gas continues to expand throughout northeastern Colorado; emissions from these operations require ongoing measurement and characterization. This presentation summarizes initial data and analysis from a summer 2014 campaign to study emissions of nitrogen compounds, methane, and other species in northeastern Colorado using a new mobile laboratory. A van was instrumented to measure NH3, N2O, NOx, NOy, CH4, CO, CO2, O3, and bioaerosols with high time resolution. By sampling in close proximity to a variety of emissions sources, the mobile laboratory facilitated accurate source identification and quantification of emissions ratios. Measurements were obtained near agricultural sites, natural gas and oil operations, and other point sources. Additionally, extensive measurements were obtained downwind from urban areas and along roadways. The relationship between ammonia and other trace gases is used to characterize sources and constrain emissions inventories.

Identification and chemical characterization of industrial particulate matter sources in southwest Spain.

PubMed

Alastuey, Andrés; Querol, Xavier; Plana, Feliciano; Viana, Mar; Ruiz, Carmen R; Sánchez de la Campa, Ana; de la Rosa, Jesús; Mantilla, Enrique; García dos Santos, Saul

2006-07-01

A detailed physical and chemical characterization of coarse particulate matter (PM10) and fine particulate matter (PM2.5) in the city of Huelva (in Southwestern Spain) was carried out during 2001 and 2002. To identify the major emission sources with a significant influence on PM10 and PM2.5, a methodology was developed based on the combination of: (1) real-time measurements of levels of PM10, PM2.5, and very fine particulate matter (PM1); (2) chemical characterization and source apportionment analysis of PM10 and PM2.5; and (3) intensive measurements in field campaigns to characterize the emission plumes of several point sources. Annual means of 37, 19, and 16 microg/m3 were obtained for the study period for PM10, PM2.5, and PM1, respectively. High PM episodes, characterized by a very fine grain size distribution, are frequently detected in Huelva mainly in the winter as the result of the impact of the industrial emission plumes on the city. Chemical analysis showed that PM at Huelva is characterized by high PO4(3-) and As levels, as expected from the industrial activities. Source apportionment analyses identified a crustal source (36% of PM10 and 31% of PM2.5); a traffic-related source (33% of PM10 and 29% of PM2.5), and a marine aerosol contribution (only in PM10, 4%). In addition, two industrial emission sources were identified in PM10 and PM2.5: (1) a petrochemical source, 13% in PM10 and 8% in PM2.5; and (2) a mixed metallurgical-phosphate source, which accounts for 11-12% of PM10 and PM2.5. In PM2.5 a secondary source has been also identified, which contributed to 17% of the mass. A complete characterization of industrial emission plumes during their impact on the ground allowed for the identification of tracer species for specific point sources, such as petrochemical, metallurgic, and fertilizer and phosphate production industries.

40 CFR 62.9501 - Identification of sources.

Code of Federal Regulations, 2010 CFR

2010-07-01

... State Deparetment of Environmental Quality submitted on January 27, 1978, certification that there are..., Organic Compounds and Nitrogen Oxide Emissions From Existing Municipal Waste Combustors With the Capacity...

40 CFR 62.1501 - Identification of sources.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Metals, Acid Gases, Organic Compounds and Nitrogen Oxides from Existing Large and Small Municipal Waste... amended at 70 FR 9229, Feb. 25, 2005] Fluoride Emissions From Phosphate Fertilizer Plants ...

40 CFR 62.1501 - Identification of sources.

Code of Federal Regulations, 2013 CFR

2013-07-01

... Metals, Acid Gases, Organic Compounds and Nitrogen Oxides from Existing Large and Small Municipal Waste... amended at 70 FR 9229, Feb. 25, 2005] Fluoride Emissions From Phosphate Fertilizer Plants ...

40 CFR 62.1501 - Identification of sources.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Metals, Acid Gases, Organic Compounds and Nitrogen Oxides from Existing Large and Small Municipal Waste... amended at 70 FR 9229, Feb. 25, 2005] Fluoride Emissions From Phosphate Fertilizer Plants ...

40 CFR 62.1501 - Identification of sources.

Code of Federal Regulations, 2014 CFR

2014-07-01

... Metals, Acid Gases, Organic Compounds and Nitrogen Oxides from Existing Large and Small Municipal Waste... amended at 70 FR 9229, Feb. 25, 2005] Fluoride Emissions From Phosphate Fertilizer Plants ...

40 CFR 62.1501 - Identification of sources.

Code of Federal Regulations, 2012 CFR

2012-07-01

... Metals, Acid Gases, Organic Compounds and Nitrogen Oxides from Existing Large and Small Municipal Waste... amended at 70 FR 9229, Feb. 25, 2005] Fluoride Emissions From Phosphate Fertilizer Plants ...

Identification of biased sectors in emission data using a combination of chemical transport model and receptor model

NASA Astrophysics Data System (ADS)

Uranishi, Katsushige; Ikemori, Fumikazu; Nakatsubo, Ryohei; Shimadera, Hikari; Kondo, Akira; Kikutani, Yuki; Asano, Katsuyoshi; Sugata, Seiji

2017-10-01

This study presented a comparison approach with multiple source apportionment methods to identify which sectors of emission data have large biases. The source apportionment methods for the comparison approach included both receptor and chemical transport models, which are widely used to quantify the impacts of emission sources on fine particulate matter of less than 2.5 μm in diameter (PM2.5). We used daily chemical component concentration data in the year 2013, including data for water-soluble ions, elements, and carbonaceous species of PM2.5 at 11 sites in the Kinki-Tokai district in Japan in order to apply the Positive Matrix Factorization (PMF) model for the source apportionment. Seven PMF factors of PM2.5 were identified with the temporal and spatial variation patterns and also retained features of the sites. These factors comprised two types of secondary sulfate, road transportation, heavy oil combustion by ships, biomass burning, secondary nitrate, and soil and industrial dust, accounting for 46%, 17%, 7%, 14%, 13%, and 3% of the PM2.5, respectively. The multiple-site data enabled a comprehensive identification of the PM2.5 sources. For the same period, source contributions were estimated by air quality simulations using the Community Multiscale Air Quality model (CMAQ) with the brute-force method (BFM) for four source categories. Both models provided consistent results for the following three of the four source categories: secondary sulfates, road transportation, and heavy oil combustion sources. For these three target categories, the models' agreement was supported by the small differences and high correlations between the CMAQ/BFM- and PMF-estimated source contributions to the concentrations of PM2.5, SO42-, and EC. In contrast, contributions of the biomass burning sources apportioned by CMAQ/BFM were much lower than and little correlated with those captured by the PMF model, indicating large uncertainties in the biomass burning emissions used in the CMAQ simulations. Thus, this comparison approach using the two antithetical models enables us to identify which sectors of emission data have large biases for improvement of future air quality simulations.

Damage source identification of reinforced concrete structure using acoustic emission technique.

PubMed

Panjsetooni, Alireza; Bunnori, Norazura Muhamad; Vakili, Amir Hossein

2013-01-01

Acoustic emission (AE) technique is one of the nondestructive evaluation (NDE) techniques that have been considered as the prime candidate for structural health and damage monitoring in loaded structures. This technique was employed for investigation process of damage in reinforced concrete (RC) frame specimens. A number of reinforced concrete RC frames were tested under loading cycle and were simultaneously monitored using AE. The AE test data were analyzed using the AE source location analysis method. The results showed that AE technique is suitable to identify the sources location of damage in RC structures.

Damage Source Identification of Reinforced Concrete Structure Using Acoustic Emission Technique

PubMed Central

Panjsetooni, Alireza; Bunnori, Norazura Muhamad; Vakili, Amir Hossein

2013-01-01

Acoustic emission (AE) technique is one of the nondestructive evaluation (NDE) techniques that have been considered as the prime candidate for structural health and damage monitoring in loaded structures. This technique was employed for investigation process of damage in reinforced concrete (RC) frame specimens. A number of reinforced concrete RC frames were tested under loading cycle and were simultaneously monitored using AE. The AE test data were analyzed using the AE source location analysis method. The results showed that AE technique is suitable to identify the sources location of damage in RC structures. PMID:23997681

Identifiability and Identification of Trace Continuous Pollutant Source

PubMed Central

Qu, Hongquan; Liu, Shouwen; Pang, Liping; Hu, Tao

2014-01-01

Accidental pollution events often threaten people's health and lives, and a pollutant source is very necessary so that prompt remedial actions can be taken. In this paper, a trace continuous pollutant source identification method is developed to identify a sudden continuous emission pollutant source in an enclosed space. The location probability model is set up firstly, and then the identification method is realized by searching a global optimal objective value of the location probability. In order to discuss the identifiability performance of the presented method, a conception of a synergy degree of velocity fields is presented in order to quantitatively analyze the impact of velocity field on the identification performance. Based on this conception, some simulation cases were conducted. The application conditions of this method are obtained according to the simulation studies. In order to verify the presented method, we designed an experiment and identified an unknown source appearing in the experimental space. The result showed that the method can identify a sudden trace continuous source when the studied situation satisfies the application conditions. PMID:24892041

40 CFR 62.10190 - Identification of Sources.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Air Emissions from Commercial and Industrial Solid Waste Incineration (ciswi) Units (section 111(d... Solid Waste Incineration Units that Commenced Construction On or Before November 30, 1999. [69 FR 9557...

40 CFR 63.5 - Preconstruction review and notification requirements.

Code of Federal Regulations, 2010 CFR

2010-07-01

...) [Reserved] (H) The type and quantity of hazardous air pollutants emitted by the source, reported in units... actual emissions data are not yet available, an estimate of the type and quantity of hazardous air..., operating design capacity, and method of operation of the source, including an identification of each type...

40 CFR 62.9631 - Identification of sources.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Landfill Gas Emissions from Existing Municipal Solid Waste Landfills (section 111(d) Plan) § 62.9631... landfills for which construction, reconstruction, or modification was commenced before May 30, 1991 and that...

Seasonal changes, identification and source apportionment of PAH in PM1.0

NASA Astrophysics Data System (ADS)

Agudelo-Castañeda, Dayana Milena; Teixeira, Elba Calesso

2014-10-01

The objective of this research was to evaluate the seasonal variation of PAHs in PM1.0, as well as to identify and quantify the contributions of each source profile using the PMF receptor model. PM1.0 samples were collected on PTFE filters from August 2011 to July 2013 in the Metropolitan Area of Porto Alegre, Rio Grande do Sul, Brazil. The samples were extracted using the EPA method TO-13A and 16 Polycyclic Aromatic Hydrocarbons (PAHs) were analyzed using a gaseous chromatograph coupled with a mass spectrometer (GC-MS). Also, the data discussed in this study were analyzed to identify the relations of the PAHs concentrations with NOx, NO, O3 and meteorological parameters (temperature, solar radiation, wind speed, relative humidity). The results showed that in winter, concentrations of total PAHs were significantly higher than in summer, thus showing their seasonal variation. The identification of emission sources by applying diagnostic ratios confirmed that PAHs in the study area originate from mobile sources, especially, from diesel and gasoline emissions. The analysis by PMF receptor model showed the contribution of these two main sources of emissions, too, followed by coal combustion, incomplete combustion/unburned petroleum and wood combustion. The toxic equivalent factors were calculated to characterize the risk of cancer from PAH exposure to PM1.0 samples, and BaP and DahA dominated BaPeq levels.

Spectral identification of a 90Sr source in the presence of masking nuclides using Maximum-Likelihood deconvolution

NASA Astrophysics Data System (ADS)

Neuer, Marcus J.

2013-11-01

A technique for the spectral identification of strontium-90 is shown, utilising a Maximum-Likelihood deconvolution. Different deconvolution approaches are discussed and summarised. Based on the intensity distribution of the beta emission and Geant4 simulations, a combined response matrix is derived, tailored to the β- detection process in sodium iodide detectors. It includes scattering effects and attenuation by applying a base material decomposition extracted from Geant4 simulations with a CAD model for a realistic detector system. Inversion results of measurements show the agreement between deconvolution and reconstruction. A detailed investigation with additional masking sources like 40K, 226Ra and 131I shows that a contamination of strontium can be found in the presence of these nuisance sources. Identification algorithms for strontium are presented based on the derived technique. For the implementation of blind identification, an exemplary masking ratio is calculated.

The Micro-Arcsecond Scintillation-Induced Variability (MASIV) Survey III. Optical Identifications and New Redshifts

NASA Technical Reports Server (NTRS)

Pursimo, Tapio; Ojha, Roopesh; Jauncey, David L.; Rickett, Barney J.; Dutka, Michael S.; Koay, Jun Yi; Lovell, James E. J.; Bignall, Hayley E.; Kedziora-Chudczer, Lucyna; Macquart, Jean-Pierre

2013-01-01

Intraday variability (IDV) of the radio emission from active galactic nuclei is now known to be predominantly due to interstellar scintillation (ISS). The MASIV (The Microarcsecond Scintillation Induced Variability) survey of 443 at spectrum sources revealed that the IDV is related to the radio flux density and redshift. A study of the physical properties of these sources has been severely handicapped by the absence of reliable redshift measurements for many of these objects. This paper presents 79 new redshifts and a critical evaluation of 233 redshifts obtained from the literature. We classify spectroscopic identifications based on emission line properties, finding that 78% of the sources have broad emission lines and are mainly FSRQs. About 16% are weak lined objects, chiefly BL Lacs, and the remaining 6% are narrow line objects. The gross properties (redshift, spectroscopic class) of the MASIV sample are similar to those of other blazar surveys. However, the extreme compactness implied by ISS favors FSRQs and BL Lacs in the MASIV sample as these are the most compact object classes. We confirm that the level of IDV depends on the 5 GHz flux density for all optical spectral types. We find that BL Lac objects tend to be more variable than broad line quasars. The level of ISS decreases substantially above a redshift of about two. The decrease is found to be generally consistent with ISS expected for beamed emission from a jet that is limited to a fixed maximum brightness temperature in the source rest frame.

Opacity meter for monitoring exhaust emissions from non-stationary sources

DOEpatents

Dec, John Edward

2000-01-01

Method and apparatus for determining the opacity of exhaust plumes from moving emissions sources. In operation, a light source is activated at a time prior to the arrival of a diesel locomotive at a measurement point, by means of a track trigger switch or the Automatic Equipment Identification system, such that the opacity measurement is synchronized with the passage of an exhaust plume past the measurement point. A beam of light from the light source passes through the exhaust plume of the locomotive and is detected by a suitable detector, preferably a high-rate photodiode. The light beam is well-collimated and is preferably monochromatic, permitting the use of a narrowband pass filter to discriminate against background light. In order to span a double railroad track and provide a beam which is substantially stronger than background, the light source, preferably a diode laser, must provide a locally intense beam. A high intensity light source is also desirable in order to increase accuracy at the high sampling rates required. Also included is a computer control system useful for data acquisition, manipulation, storage and transmission of opacity data and the identification of the associated diesel engine to a central data collection center.

Composition and source apportionment of PM1 at urban site Kanpur in India using PMF coupled with CBPF

NASA Astrophysics Data System (ADS)

Rai, Pragati; Chakraborty, Abhishek; Mandariya, Anil Kumar; Gupta, Tarun

2016-09-01

This study addresses the three major questions: (1) what are the emission sources of PM1 which are affecting the study area; (2) where do these emission sources come from; and (3) is there any temporal variation in the emission sources. To address these issues, two advanced statistical methods are described in this paper. Identification of emission sources was performed by EPA PMF (v 5.0) and to understand the temporal variability, sampling was done for three winter seasons 2008-09, 2009-10 and 2011-12 within Kanpur city. To identify the possible source directions, Conditional Bivariate Probability function (CBPF) was used. The average PM1 concentration was higher in 2008-09 followed by 2011-12 and 2009-10 winter seasons. 2008-09 winter showed sources such as secondary sources mixed with power plant emission (42.8%), industrial emission (32.3%), coal combustion, brick kilns and vehicular emission (13.2%) and residual oil combustion and road dust (11.7%). The major contributors during winter season 2009-10 were secondary sources (33.1%), biomass burning (23.3%), heavy oil combustion (13%), vehicular emission mixed with crustal dust (11.3%), leather tanning industries (10.3%), industrial emission (4%), coal combustion and brick kilns (3.4%) and solid waste burning and incineration (1.5%) compared to secondary sources mixed with biomass burning (42.3%), industrial emission and crustal dust (35.1%) and vehicular emission and brick kilns (22.6%) during 2011-12 winter season. PMF model revealed that secondary sources were the main contributors for all the three winter seasons followed by biomass burning and power plant emission. The results of CBPF analysis agreed well with the locations of known local point sources., e.g. in the case of industrial emissions, the maximum probability was in the direction between NES direction where almost all the major industries are located in and around Kanpur while in the opposite direction the probability of biomass burning was high due to a rural area in NWS direction.

The application of magnetic measurements for the characterization of atmospheric particulate pollution within the airport environment.

PubMed

Jones, S; Richardson, N; Bennett, M; Hoon, S R

2015-01-01

The significant increase in global air travel which has occurred during the last fifty years has generated growing concern regarding the potential impacts associated with increasing emissions of atmospheric particulate matter (PM) on health and the environment. PM within the airport environment may be derived from a range of sources. To date, however, the identification of individual sources of airport derived PM has remained elusive but constitutes a research priority for the aviation industry.The aim of this research was to identify distinctive and characteristic fingerprints of atmospheric PM derived from various sources in an airport environment through the use of environmental magnetic measurements. PM samples from aircraft engine emissions, brake wear and tire wear residues have been obtained from a range of different aircraft and engine types. Samples have been analyzed utilizing a range of magnetic mineral properties indicative of magnetic mineralogy and grain size. Results indicate that the dusts from the three 'aircraft' sources, (i.e. engines, brakes and tires) display distinctive magnetic mineral characteristics which may serve as 'magnetic fingerprints' for these sources. Magnetic measurements of runway dusts collected at different locations on the runway surface also show contrasting magnetic characteristics which, when compared with those of the aircraft-derived samples, suggest that they may relate to different sources characteristic of aircraft emissions at various stages of the take-off/landing cycle. The findings suggest that magnetic measurements could have wider applicability for the differentiation and identification of PM within the airport environment.

Temporal variation and source identification of black carbon at Lin'an and Longfengshan regional background stations in China

NASA Astrophysics Data System (ADS)

Cheng, Siyang; Wang, Yaqiang; An, Xingqin

2017-12-01

Black carbon (BC) is a component of fine particulate matter (PM2.5), associated with climate, weather, air quality, and people's health. However, studies on temporal variation of atmospheric BC concentration at background stations in China and its source area identification are lacking. In this paper, we use 2-yr BC observations from two background stations, Lin'an (LAN) and Longfengshan (LFS), to perform the investigation. The results show that the mean diurnal variation of BC has two significant peaks at LAN while different characteristics are found in the BC variation at LFS, which are probably caused by the difference in emission source contributions. Seasonal variation of monthly BC shows double peaks at LAN but a single peak at LFS. The annual mean concentrations of BC at LAN and LFS decrease by 1.63 and 0.26 μg m-3 from 2009 to 2010, respectively. The annual background concentration of BC at LAN is twice higher than that at LFS. The major source of the LAN BC is industrial emission while the source of the LFS BC is residential emission. Based on transport climatology on a 7-day timescale, LAN and LFS stations are sensitive to surface emissions respectively in belt or approximately circular area, which are dominated by summer monsoon or colder land air flows in Northwest China. In addition, we statistically analyze the BC source regions by using BC observation and FLEXible PARTicle dispersion model (FLEXPART) simulation. In summer, the source regions of BC are distributed in the northwest and south of LAN and the southwest of LFS. Low BC concentration is closely related to air mass from the sea. In winter, the source regions of BC are concentrated in the west and south of LAN and the northeast of the threshold area of s tot at LFS. The cold air mass in the northwest plays an important role in the purification of atmospheric BC. On a yearly scale, sources of BC are approximately from five provinces in the northwest/southeast of LAN and the west of LFS. These findings are helpful in reducing BC emission and controlling air pollution.

40 CFR 62.9501 - Identification of sources.

Code of Federal Regulations, 2011 CFR

2011-07-01

... no existing sulfuric acid plants in the State subject to part 60, subpart B of this chapter. [44 FR..., Organic Compounds and Nitrogen Oxide Emissions From Existing Municipal Waste Combustors With the Capacity...

40 CFR 62.9501 - Identification of sources.

Code of Federal Regulations, 2014 CFR

2014-07-01

... no existing sulfuric acid plants in the State subject to part 60, subpart B of this chapter. [44 FR..., Organic Compounds and Nitrogen Oxide Emissions From Existing Municipal Waste Combustors With the Capacity...

40 CFR 62.9501 - Identification of sources.

Code of Federal Regulations, 2012 CFR

2012-07-01

... no existing sulfuric acid plants in the State subject to part 60, subpart B of this chapter. [44 FR..., Organic Compounds and Nitrogen Oxide Emissions From Existing Municipal Waste Combustors With the Capacity...

40 CFR 62.9501 - Identification of sources.

Code of Federal Regulations, 2013 CFR

2013-07-01

... no existing sulfuric acid plants in the State subject to part 60, subpart B of this chapter. [44 FR..., Organic Compounds and Nitrogen Oxide Emissions From Existing Municipal Waste Combustors With the Capacity...

An Optimal Image-Based Method for Identification of Acoustic Emission (AE) Sources in Plate-Like Structures Using a Lead Zirconium Titanate (PZT) Sensor Array.

PubMed

Yan, Gang; Zhou, Li

2018-02-21

This paper proposes an innovative method for identifying the locations of multiple simultaneous acoustic emission (AE) events in plate-like structures from the view of image processing. By using a linear lead zirconium titanate (PZT) sensor array to record the AE wave signals, a reverse-time frequency-wavenumber (f-k) migration is employed to produce images displaying the locations of AE sources by back-propagating the AE waves. Lamb wave theory is included in the f-k migration to consider the dispersive property of the AE waves. Since the exact occurrence time of the AE events is usually unknown when recording the AE wave signals, a heuristic artificial bee colony (ABC) algorithm combined with an optimal criterion using minimum Shannon entropy is used to find the image with the identified AE source locations and occurrence time that mostly approximate the actual ones. Experimental studies on an aluminum plate with AE events simulated by PZT actuators are performed to validate the applicability and effectiveness of the proposed optimal image-based AE source identification method.

An Optimal Image-Based Method for Identification of Acoustic Emission (AE) Sources in Plate-Like Structures Using a Lead Zirconium Titanate (PZT) Sensor Array

PubMed Central

Zhou, Li

2018-01-01

This paper proposes an innovative method for identifying the locations of multiple simultaneous acoustic emission (AE) events in plate-like structures from the view of image processing. By using a linear lead zirconium titanate (PZT) sensor array to record the AE wave signals, a reverse-time frequency-wavenumber (f-k) migration is employed to produce images displaying the locations of AE sources by back-propagating the AE waves. Lamb wave theory is included in the f-k migration to consider the dispersive property of the AE waves. Since the exact occurrence time of the AE events is usually unknown when recording the AE wave signals, a heuristic artificial bee colony (ABC) algorithm combined with an optimal criterion using minimum Shannon entropy is used to find the image with the identified AE source locations and occurrence time that mostly approximate the actual ones. Experimental studies on an aluminum plate with AE events simulated by PZT actuators are performed to validate the applicability and effectiveness of the proposed optimal image-based AE source identification method. PMID:29466310

Methane source identification in Boston, Massachusetts using isotopic and ethane measurements

NASA Astrophysics Data System (ADS)

Down, A.; Jackson, R. B.; Plata, D.; McKain, K.; Wofsy, S. C.; Rella, C.; Crosson, E.; Phillips, N. G.

2012-12-01

Methane has substantial greenhouse warming potential and is the principle component of natural gas. Fugitive natural gas emissions could be a significant source of methane to the atmosphere. However, the cumulative magnitude of natural gas leaks is not yet well constrained. We used a combination of point source measurements and ambient monitoring to characterize the methane sources in the Boston urban area. We developed distinct fingerprints for natural gas and multiple biogenic methane sources based on hydrocarbon concentration and isotopic composition. We combine these data with periodic measurements of atmospheric methane and ethane concentration to estimate the fractional contribution of natural gas and biogenic methane sources to the cumulative urban methane flux in Boston. These results are used to inform an inverse model of urban methane concentration and emissions.

Ammonia emissions from non-agricultural sources in the UK

NASA Astrophysics Data System (ADS)

Sutton, M. A.; Dragosits, U.; Tang, Y. S.; Fowler, D.

A detailed literature review has been undertaken of the magnitude of non-agricultural sources of ammonia (NH 3) in the United Kingdom. Key elements of the work included estimation of nitrogen (N) excreted by different sources (birds, animals, babies, human sweat), review of miscellaneous combustion sources, as well as identification of industrial sources and use of NH 3 as a solvent. Overall the total non-agricultural emission of NH 3 from the UK in 1996 is estimated here as 54 (27-106) kt NH 3-N yr -1, although this includes 11 (6-23) kt yr -1 from agriculture related sources (sewage sludge spreading, biomass burning and agro-industry). Compared with previous estimates for 1990, component source magnitudes have changed both because of revised average emissions per source unit (emission factors) and changes in the source activity between 1990 and 1996. Sources with larger average emission factors than before include horses, wild animals and sea bird colonies, industry, sugar beet processing, household products and non-agricultural fertilizer use, with the last three sources being included for the first time. Sources with smaller emission factors than before include: land spreading of sewage sludge, direct human emissions (sweat, breath, smoking, infants), pets (cats and dogs) and fertilizer manufacture. Between 1990 and 1996 source activities increased for sewage spreading (due to reduced dumping at sea) and transport (due to increased use of catalytic converters), but decreased for coal combustion. Combined with the current UK estimates of agricultural NH 3 emissions of 229 kt N yr -1 (1996), total UK NH 3 emissions are estimated at 283 kt N yr -1. Allowing for an import of reduced nitrogen (NH x) of 30 kt N yr -1 and deposition of 230 kt N yr -1, these figures imply an export of 83 kt NH 3-N yr -1. Although export is larger than previously estimated, due to the larger contribution of non-agricultural NH 3 emissions, it is still insufficient to balance the UK budget, for which around 150 kt NH 3-N are estimated to be exported. The shortfall in the budget is, nevertheless, well within the range of uncertainty of the total emissions.

Comparison of receptor models for source apportionment of the PM10 in Zaragoza (Spain).

PubMed

Callén, M S; de la Cruz, M T; López, J M; Navarro, M V; Mastral, A M

2009-08-01

Receptor models are useful to understand the chemical and physical characteristics of air pollutants by identifying their sources and by estimating contributions of each source to receptor concentrations. In this work, three receptor models based on principal component analysis with absolute principal component scores (PCA-APCS), Unmix and positive matrix factorization (PMF) were applied to study for the first time the apportionment of the airborne particulate matter less or equal than 10microm (PM10) in Zaragoza, Spain, during 1year sampling campaign (2003-2004). The PM10 samples were characterized regarding their concentrations in inorganic components: trace elements and ions and also organic components: polycyclic aromatic hydrocarbons (PAH) not only in the solid phase but also in the gas phase. A comparison of the three receptor models was carried out in order to do a more robust characterization of the PM10. The three models predicted that the major sources of PM10 in Zaragoza were related to natural sources (60%, 75% and 47%, respectively, for PCA-APCS, Unmix and PMF) although anthropogenic sources also contributed to PM10 (28%, 25% and 39%). With regard to the anthropogenic sources, while PCA and PMF allowed high discrimination in the sources identification associated with different combustion sources such as traffic and industry, fossil fuel, biomass and fuel-oil combustion, heavy traffic and evaporative emissions, the Unmix model only allowed the identification of industry and traffic emissions, evaporative emissions and heavy-duty vehicles. The three models provided good correlations between the experimental and modelled PM10 concentrations with major precision and the closest agreement between the PMF and PCA models.

40 CFR 62.6121 - Identification of sources-negative declaration.

Code of Federal Regulations, 2010 CFR

2010-07-01

...—negative declaration. The Mississippi Bureau of Pollution Control submitted on March 6, 1985, a letter..., subpart B of this chapter. [50 FR 26204, June 25, 1985] Total Reduced Sulfur Emissions From Kraft Pulp...

Low-cost, high-density sensor network for urban emission monitoring: BEACO2N

NASA Astrophysics Data System (ADS)

Kim, J.; Shusterman, A.; Lieschke, K.; Newman, C.; Cohen, R. C.

2017-12-01

In urban environments, air quality is spatially and temporally heterogeneous as diverse emission sources create a high degree of variability even at the neighborhood scale. Conventional air quality monitoring relies on continuous measurements with limited spatial resolution or passive sampling with high-density and low temporal resolution. Either approach averages the air quality information over space or time and hinders our attempts to understand emissions, chemistry, and human exposure in the near-field of emission sources. To better capture the true spatio-temporal heterogeneity of urban conditions, we have deployed a low-cost, high-density air quality monitoring network in San Francisco Bay Area distributed at 2km horizontal spacing. The BErkeley Atmospheric CO2 Observation Network (BEACO2N) consists of approximately 50 sensor nodes, measuring CO2, CO, NO, NO2, O­3, and aerosol. Here we describe field-based calibration approaches that are consistent with the low-cost strategy of the monitoring network. Observations that allow inference of emission factors and identification of specific local emission sources will also be presented.

Identification of the odour and chemical composition of alumina refinery air emissions.

PubMed

Coffey, P S; Ioppolo-Armanios, M

2004-01-01

Alcoa World Alumina Australia has undertaken comprehensive air emissions monitoring aimed at characterising and quantifying the complete range of emissions to the atmosphere from Bayer refining of alumina at its Western Australian refineries. To the best of our knowledge, this project represents the most complete air emissions inventory of a Bayer refinery conducted in the worldwide alumina industry. It adds considerably to knowledge of air emission factors available for use in emissions estimation required under national pollutant release and transfer registers (NPRTs), such as the Toxic Releases Inventory, USA, and the National Pollutant Inventory, Australia. It also allows the preliminary identification of the key chemical components responsible for characteristic alumina refinery odours and the contribution of these components to the quality, or hedonic tone, of the odours. The strength and acceptability of refinery odours to employees and neighbours appears to be dependent upon where and in what proportion the odorous gases have been emitted from the refineries. This paper presents the results of the programme and develops a basis for classifying the odour properties of the key emission sources in the alumina-refining process.

Identification of HESS J1303-631 as a pulsar wind nebula through γ-ray, X-ray, and radio observations

NASA Astrophysics Data System (ADS)

H.E.S.S. Collaboration; Abramowski, A.; Acero, F.; Aharonian, F.; Akhperjanian, A. G.; Anton, G.; Balenderan, S.; Balzer, A.; Barnacka, A.; Becherini, Y.; Becker, J.; Bernlöhr, K.; Birsin, E.; Biteau, J.; Bochow, A.; Boisson, C.; Bolmont, J.; Bordas, P.; Brucker, J.; Brun, F.; Brun, P.; Bulik, T.; Büsching, I.; Carrigan, S.; Casanova, S.; Cerruti, M.; Chadwick, P. M.; Charbonnier, A.; Chaves, R. C. G.; Cheesebrough, A.; Cologna, G.; Conrad, J.; Couturier, C.; Dalton, M.; Daniel, M. K.; Davids, I. D.; Degrange, B.; Deil, C.; Dickinson, H. J.; Djannati-Ataï, A.; Domainko, W.; Drury, L. O'C.; Dubus, G.; Dutson, K.; Dyks, J.; Dyrda, M.; Egberts, K.; Eger, P.; Espigat, P.; Fallon, L.; Farnier, C.; Fegan, S.; Feinstein, F.; Fernandes, M. V.; Fiasson, A.; Fontaine, G.; Förster, A.; Füßling, M.; Gajdus, M.; Gallant, Y. A.; Garrigoux, T.; Gast, H.; Gérard, L.; Giebels, B.; Glicenstein, J. F.; Glück, B.; Göring, D.; Grondin, M.-H.; Häffner, S.; Hague, J. D.; Hahn, J.; Hampf, D.; Harris, J.; Hauser, M.; Heinz, S.; Heinzelmann, G.; Henri, G.; Hermann, G.; Hillert, A.; Hinton, J. A.; Hofmann, W.; Hofverberg, P.; Holler, M.; Horns, D.; Jacholkowska, A.; Jahn, C.; Jamrozy, M.; Jung, I.; Kastendieck, M. A.; Katarzyński, K.; Katz, U.; Kaufmann, S.; Khélifi, B.; Klochkov, D.; Kluźniak, W.; Kneiske, T.; Komin, Nu.; Kosack, K.; Kossakowski, R.; Krayzel, F.; Laffon, H.; Lamanna, G.; Lenain, J.-P.; Lennarz, D.; Lohse, T.; Lopatin, A.; Lu, C.-C.; Marandon, V.; Marcowith, A.; Masbou, J.; Maurin, G.; Maxted, N.; Mayer, M.; McComb, T. J. L.; Medina, M. C.; Méhault, J.; Menzler, U.; Moderski, R.; Mohamed, M.; Moulin, E.; Naumann, C. L.; Naumann-Godo, M.; de Naurois, M.; Nedbal, D.; Nekrassov, D.; Nguyen, N.; Nicholas, B.; Niemiec, J.; Nolan, S. J.; Ohm, S.; de Oña Wilhelmi, E.; Opitz, B.; Ostrowski, M.; Oya, I.; Panter, M.; Paz Arribas, M.; Pekeur, N. W.; Pelletier, G.; Perez, J.; Petrucci, P.-O.; Peyaud, B.; Pita, S.; Pühlhofer, G.; Punch, M.; Quirrenbach, A.; Raue, M.; Reimer, A.; Reimer, O.; Renaud, M.; de los Reyes, R.; Rieger, F.; Ripken, J.; Rob, L.; Rosier-Lees, S.; Rowell, G.; Rudak, B.; Rulten, C. B.; Sahakian, V.; Sanchez, D. A.; Santangelo, A.; Schlickeiser, R.; Schulz, A.; Schwanke, U.; Schwarzburg, S.; Schwemmer, S.; Sheidaei, F.; Skilton, J. L.; Sol, H.; Spengler, G.; Stawarz, Ł.; Steenkamp, R.; Stegmann, C.; Stinzing, F.; Stycz, K.; Sushch, I.; Szostek, A.; Tavernet, J.-P.; Terrier, R.; Tluczykont, M.; Valerius, K.; van Eldik, C.; Vasileiadis, G.; Venter, C.; Viana, A.; Vincent, P.; Völk, H. J.; Volpe, F.; Vorobiov, S.; Vorster, M.; Wagner, S. J.; Ward, M.; White, R.; Wierzcholska, A.; Zacharias, M.; Zajczyk, A.; Zdziarski, A. A.; Zech, A.; Zechlin, H.-S.

2012-12-01

Aims: The previously unidentified very high-energy (VHE; E > 100 GeV) γ-ray source HESS J1303-631, discovered in 2004, is re-examined including new data from the H.E.S.S. Cherenkov telescope array in order to identify this object. Archival data from the XMM-Newton X-ray satellite and from the PMN radio survey are also examined. Methods: Detailed morphological and spectral studies of VHE γ-ray emission as well as of the XMM-Newton X-ray data are performed. Radio data from the PMN survey are used as well to construct a leptonic model of the source. The γ-ray and X-ray spectra and radio upper limit are used to construct a one zone leptonic model of the spectral energy distribution (SED). Results: Significant energy-dependent morphology of the γ-ray source is detected with high-energy emission (E > 10 TeV) positionally coincident with the pulsar PSR J1301-6305 and lower energy emission (E < 2 TeV) extending 0.4° to the southeast of the pulsar. The spectrum of the VHE source can be described with a power-law with an exponential cut-off N0 = (5.6 ± 0.5) × 10-12 TeV-1 cm-2 s-1, Γ = 1.5 ± 0.2) and Ecut = (7.7 ± 2.2) TeV. The pulsar wind nebula (PWN) is also detected in X-rays, extending 2-3' from the pulsar position towards the center of the γ-ray emission region. A potential radio counterpart from the PMN survey is also discussed, showing a hint for a counterpart at the edge of the X-ray PWN trail and is taken as an upper limit in the SED. The extended X-ray PWN has an unabsorbed flux of F_2{-10 keV ˜ 1.6+0.2-0.4× 10-13 erg cm-2 s-1} and is detected at a significance of 6.5σ. The SED is well described by a one zone leptonic scenario which, with its associated caveats, predicts a very low average magnetic field for this source. Conclusions: Significant energy-dependent morphology of this source, as well as the identification of an associated X-ray PWN from XMM-Newton observations enable identification of the VHE source as an evolved PWN associated to the pulsar PSR J1301-6305. This identification is supported by the one zone leptonic model, which suggests that the energetics of the γ-ray and X-ray radiation are such that they may have a similar origin in the pulsar nebula. However, the large discrepancy in emission region sizes and the low level of synchrotron radiation suggest a multi-population leptonic nature. The low implied magnetic field suggests that the PWN has undergone significant expansion. This would explain the low level of synchrotron radiation and the difficulty in detecting counterparts at lower energies, the reason this source was originally classified as a "dark" VHE γ-ray source.

VOC source identification from personal and residential indoor, outdoor and workplace microenvironment samples in EXPOLIS-Helsinki, Finland

NASA Astrophysics Data System (ADS)

Edwards, Rufus D.; Jurvelin, J.; Koistinen, K.; Saarela, K.; Jantunen, M.

Principal component analyses (varimax rotation) were used to identify common sources of 30 target volatile organic compounds (VOCs) in residential outdoor, residential indoor and workplace microenvironment and personal 48-h exposure samples, as a component of the EXPOLIS-Helsinki study. Variability in VOC concentrations in residential outdoor microenvironments was dominated by compounds associated with long-range transport of pollutants, followed by traffic emissions, emissions from trees and product emissions. Variability in VOC concentrations in environmental tobacco smoke (ETS) free residential indoor environments was dominated by compounds associated with indoor cleaning products, followed by compounds associated with traffic emissions, long-range transport of pollutants and product emissions. Median indoor/outdoor ratios for compounds typically associated with traffic emissions and long-range transport of pollutants exceeded 1, in some cases quite considerably, indicating substantial indoor source contributions. Changes in the median indoor/outdoor ratios during different seasons reflected different seasonal ventilation patterns as increased ventilation led to dilution of those VOC compounds in the indoor environment that had indoor sources. Variability in workplace VOC concentrations was dominated by compounds associated with traffic emissions followed by product emissions, long-range transport and air fresheners. Variability in VOC concentrations in ETS free personal exposure samples was dominated by compounds associated with traffic emissions, followed by long-range transport, cleaning products and product emissions. VOC sources in personal exposure samples reflected the times spent in different microenvironments, and personal exposure samples were not adequately represented by any one microenvironment, demonstrating the need for personal exposure sampling.

THE MICRO-ARCSECOND SCINTILLATION-INDUCED VARIABILITY (MASIV) SURVEY. III. OPTICAL IDENTIFICATIONS AND NEW REDSHIFTS

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

Pursimo, Tapio; Ojha, Roopesh; Jauncey, David L.

2013-04-10

Intraday variability (IDV) of the radio emission from active galactic nuclei is now known to be predominantly due to interstellar scintillation (ISS). The MASIV (The Micro-Arcsecond Scintillation-Induced Variability) survey of 443 flat spectrum sources revealed that the IDV is related to the radio flux density and redshift. A study of the physical properties of these sources has been severely handicapped by the absence of reliable redshift measurements for many of these objects. This paper presents 79 new redshifts and a critical evaluation of 233 redshifts obtained from the literature. We classify spectroscopic identifications based on emission line properties, finding thatmore » 78% of the sources have broad emission lines and are mainly FSRQs. About 16% are weak lined objects, chiefly BL Lacs, and the remaining 6% are narrow line objects. The gross properties (redshift, spectroscopic class) of the MASIV sample are similar to those of other blazar surveys. However, the extreme compactness implied by ISS favors FSRQs and BL Lacs in the MASIV sample as these are the most compact object classes. We confirm that the level of IDV depends on the 5 GHz flux density for all optical spectral types. We find that BL Lac objects tend to be more variable than broad line quasars. The level of ISS decreases substantially above a redshift of about two. The decrease is found to be generally consistent with ISS expected for beamed emission from a jet that is limited to a fixed maximum brightness temperature in the source rest frame.« less

Identification of specific sources of airborne particles emitted from within a complex industrial (steelworks) site

NASA Astrophysics Data System (ADS)

Beddows, D. C. S.; Harrison, Roy M.

2018-06-01

A case study is provided of the development and application of methods to identify and quantify specific sources of emissions from within a large complex industrial site. Methods include directional analysis of concentrations, chemical source tracers and correlations with gaseous emissions. Extensive measurements of PM10, PM2.5, trace gases, particulate elements and single particle mass spectra were made at sites around the Port Talbot steelworks in 2012. By using wind direction data in conjunction with real-time or hourly-average pollutant concentration measurements, it has been possible to locate areas within the steelworks associated with enhanced pollutant emissions. Directional analysis highlights the Slag Handling area of the works as the most substantial source of elevated PM10 concentrations during the measurement period. Chemical analyses of air sampled from relevant wind directions is consistent with the anticipated composition of slags, as are single particle mass spectra. Elevated concentrations of PM10 are related to inverse distance from the Slag Handling area, and concentrations increase with increased wind speed, consistent with a wind-driven resuspension source. There also appears to be a lesser source associated with Sinter Plant emissions affecting PM10 concentrations at the Fire Station monitoring site. The results are compared with a ME2 study using some of the same data, and shown to give a clearer view of the location and characteristics of emission sources, including fugitive dusts.

Methodical principles of recognition different source types in an acoustic-emission testing of metal objects

NASA Astrophysics Data System (ADS)

Bobrov, A. L.

2017-08-01

This paper presents issues of identification of various AE sources in order to increase the information value of AE method. This task is especially relevant for complex objects, when factors that affect an acoustic path on an object of testing significantly affect parameters of signals recorded by sensor. Correlation criteria, sensitive to type of AE source in metal objects is determined in the article.

Elemental composition of airborne particulates and source identification - An extensive one year survey. [in Cleveland, OH

NASA Technical Reports Server (NTRS)

King, R. B.; Fordyce, J. S.; Antoine, A. C.; Leibecki, H. F.; Neustadter, H. E.; Sidik, S. M.

1976-01-01

Concentrations of 60 chemical elements in the airborne particulate matter were measured at 16 sites in Cleveland, OH over a 1 year period during 1971 and 1972 (45 to 50 sampling days). Analytical methods used included instrumental neutron activation, emission spectroscopy, and combustion techniques. Uncertainties in the concentrations associated with the sampling procedures, the analytical methods, the use of several analytical facilities, and samples with concentrations below the detection limits are evaluated in detail. The data are discussed in relation to other studies and source origins. The trace constituent concentrations as a function of wind direction are used to suggest a practical method for air pollution source identification.

Spectral identification/elimination of molecular species in spacecraft glow

NASA Technical Reports Server (NTRS)

Green, B. D.; Marinelli, W. J.; Rawlins, W. T.

1985-01-01

Computer models of molecular electronic and vibrational emission intensities were developed. Known radiative emission rates (Einstein coefficients) permit the determination of relative excited state densities from spectral intensities. These codes were applied to the published spectra of glow above shuttle surface and to the Spacelab 1 results of Torr and Torr. The theoretical high-resolution spectra were convolved with the appropriate instrumental slit functions to allow accurate comparison with data. The published spacelab spectrum is complex but N2+ Meinel emission can be clearly identified in the ram spectrum. M2 First Positive emission does not correlate well with observed features, nor does the CN Red System. Spectral overlay comparisons are presented. The spectrum of glow above shuttle surfaces, in contrast to the ISO data, is not highly structured. Diatomic molecular emission was matched to the observed spectral shape. Source excitation mechanisms such as (oxygen atom)-(surface species) reaction product chemiluminescence, surface recombination, or resonance fluorescent re-emission will be discussed for each tentative assignment. These assignments are the necessary first analytical step toward mechanism identification. Different glow mechanisms will occur above surfaces under different orbital conditions.

Positive matrix factorization and trajectory modelling for source identification: A new look at Indian Ocean Experiment ship observations

NASA Astrophysics Data System (ADS)

Bhanuprasad, S. G.; Venkataraman, Chandra; Bhushan, Mani

The sources of aerosols on a regional scale over India have only recently received attention in studies using back trajectory analysis and chemical transport modelling. Receptor modelling approaches such as positive matrix factorization (PMF) and the potential source contribution function (PSCF) are effective tools in source identification of urban and regional-scale pollution. In this work, PMF and PSCF analysis is applied to identify categories and locations of sources that influenced surface concentrations of aerosols in the Indian Ocean Experiment (INDOEX) domain measured on-board the research vessel Ron Brown [Quinn, P.K., Coffman, D.J., Bates, T.S., Miller, T.L., Johnson, J.E., Welton, E.J., et al., 2002. Aerosol optical properties during INDOEX 1999: means, variability, and controlling factors. Journal of Geophysical Research 107, 8020, doi:10.1029/2000JD000037]. Emissions inventory information is used to identify sources co-located with probable source regions from PSCF. PMF analysis identified six factors influencing PM concentrations during the INDOEX cruise of the Ron Brown including a biomass combustion factor (35-40%), three industrial emissions factors (35-40%), primarily secondary sulphate-nitrate, balance trace elements and Zn, and two dust factors (20-30%) of Si- and Ca-dust. The identified factors effectively predict the measured submicron PM concentrations (slope of regression line=0.90±0.20; R2=0.76). Probable source regions shifted based on changes in surface and elevated flows during different times in the ship cruise. They were in India in the early part of the cruise, but in west Asia, south-east Asia and Africa, during later parts of the cruise. Co-located sources include coal-fired electric utilities, cement, metals and petroleum production in India and west Asia, biofuel combustion for energy and crop residue burning in India, woodland/forest burning in north sub-Saharan Africa and forest burning in south-east Asia. Significant findings are equivalent contributions of biomass combustion and industrial emissions to the measured aerosol surface concentrations, the origin of carbonaceous aerosols largely from biomass combustion and the identification of probable source regions in Africa, west Asia, the Arabian peninsula and south-east Asia, in addition to India, which affected particulate matter concentrations over parts of the INDOEX domain covered by the Ron Brown cruise.

40 CFR 62.4975 - Identification of sources.

Code of Federal Regulations, 2012 CFR

2012-07-01

... Section 62.4975 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS...) Penobscot Energy Recovery Company, Orrington, Maine. (b) Maine Energy Recovery Company, Biddeford, Maine. (c) Regional Waste Systems, Inc., Portland, Maine. [63 FR 68397, Dec. 11, 1998] Air Emissions From Existing...

40 CFR 62.4975 - Identification of sources.

Code of Federal Regulations, 2013 CFR

2013-07-01

... Section 62.4975 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS...) Penobscot Energy Recovery Company, Orrington, Maine. (b) Maine Energy Recovery Company, Biddeford, Maine. (c) Regional Waste Systems, Inc., Portland, Maine. [63 FR 68397, Dec. 11, 1998] Air Emissions From Existing...

40 CFR 62.4975 - Identification of sources.

Code of Federal Regulations, 2014 CFR

2014-07-01

... Section 62.4975 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS...) Penobscot Energy Recovery Company, Orrington, Maine. (b) Maine Energy Recovery Company, Biddeford, Maine. (c) Regional Waste Systems, Inc., Portland, Maine. [63 FR 68397, Dec. 11, 1998] Air Emissions From Existing...

40 CFR 62.4975 - Identification of sources.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Section 62.4975 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS...) Penobscot Energy Recovery Company, Orrington, Maine. (b) Maine Energy Recovery Company, Biddeford, Maine. (c) Regional Waste Systems, Inc., Portland, Maine. [63 FR 68397, Dec. 11, 1998] Air Emissions From Existing...

40 CFR 62.1102 - Identification of sources.

Code of Federal Regulations, 2011 CFR

2011-07-01

...) Allied Chemical Corporation in Alameda County. (b) Monsanto Company in Alameda County. (c) Occidental Chemical Company in Fresno County. (d) Stauffer Chemical Company in Alameda County. (e) Valley Nitrogen Products, Inc. in Kern County. Fluoride Emissions From Primary Aluminum Reduction Plants ...

40 CFR 62.1102 - Identification of sources.

Code of Federal Regulations, 2014 CFR

2014-07-01

...) Allied Chemical Corporation in Alameda County. (b) Monsanto Company in Alameda County. (c) Occidental Chemical Company in Fresno County. (d) Stauffer Chemical Company in Alameda County. (e) Valley Nitrogen Products, Inc. in Kern County. Fluoride Emissions From Primary Aluminum Reduction Plants ...

40 CFR 62.1102 - Identification of sources.

Code of Federal Regulations, 2012 CFR

2012-07-01

...) Allied Chemical Corporation in Alameda County. (b) Monsanto Company in Alameda County. (c) Occidental Chemical Company in Fresno County. (d) Stauffer Chemical Company in Alameda County. (e) Valley Nitrogen Products, Inc. in Kern County. Fluoride Emissions From Primary Aluminum Reduction Plants ...

40 CFR 62.1102 - Identification of sources.

Code of Federal Regulations, 2013 CFR

2013-07-01

...) Allied Chemical Corporation in Alameda County. (b) Monsanto Company in Alameda County. (c) Occidental Chemical Company in Fresno County. (d) Stauffer Chemical Company in Alameda County. (e) Valley Nitrogen Products, Inc. in Kern County. Fluoride Emissions From Primary Aluminum Reduction Plants ...

Optical identification of radio-loud active galactic nuclei in the ROSAT-Green-Bank sample with SDSS spectroscopy

NASA Astrophysics Data System (ADS)

Wang, De-Liang; Wang, Jian-Guo; Dong, Xiao-Bo

2009-10-01

Results of extended and refined optical identification of 181 radio/X-ray sources in the RASS-Green Bank (RGB) catalog are presented (Brinkmann et al. 1997) which have been spectroscopically observed in the Sloan Digital Sky Survey (SDSS) DR5. The SDSS spectra of the optical counterparts are modeled in a careful and self-consistent way by incorporating the host galaxy's starlight. Optical emission line parameters are presented, which are derived accurately and reliably, along with the radio 1.4-5 GHz spectral indices estimated using (non-simultaneous) archival data. For 72 sources, the identifications are presented for the first time. It is confirmed that the majority of strong radio/X-ray emitters are radio-loud active galactic nuclei (AGNs), particularly blazars. Taking advantage of the high spectral quality and resolution and our refined spectral modeling, we are able to disentangle narrow line radio galaxies (NLRGs), as vaguely termed in most previous identification work, into Seyfert II galaxies and LINERs (low-ionization nuclear emission regions), based on the standard emission line diagnostics. The NLRGs in the RGB sample, mostly belonging to 'weak line radio galaxies', are found to have optical spectra consistent predominantly with LINERs, and only a small fraction with Seyfert II galaxies. A small number of LINERs have radio power as high as 1023 - 1026 W Hz-1 at 5 GHz, being among the strongest radio emitting LINERs known so far. Two sources are identified with radio-loud narrow line Seyfert 1 galaxies (NLS1s), a class of rare objects. The presence is also confirmed of flat-spectrum radio quasars whose radio-optical-X-ray effective spectral indices are similar to those of High-energy peaked BL Lacs (HBLs), as suggested by Padovani et al., although it is still a debate as to whether this is the case for their actual spectral energy distributions.

In-vitro bacterial identification using fluorescence spectroscopy with an optical fiber system

NASA Astrophysics Data System (ADS)

Spector, Brian C.; Werkhaven, Jay A.; Smith, Dana; Reinisch, Lou

2000-05-01

Acute otitis media (AOM) remains a source of significant morbidity in children. With the emergence of antibiotic resistant strains of bacteria, tympanocentesis has become an important method of bacterial identification in the setting of treatment failures. Previous studies described a prototype system for the non-invasive fluorescence identification of bacteria in vitro. We demonstrate the addition of an optical fiber to allow for the identification of a specimen distant to the spectrofluorometer. Emission spectra from three bacteria, Streptococcus pneumoniae, Haemophilus influenzae, and Staphylococcus aureus were successfully obtained in vitro. This represents a necessary step prior to the study of in vivo identification of bacteria in AOM using fluorescence spectroscopy.

Evolution of X-ray astronomy

NASA Technical Reports Server (NTRS)

Rossj, B.

1981-01-01

The evolution of X-ray astronomy up to the launching of the Einstein observatory is presented. The evaluation proceeded through the following major steps: (1) discovery of an extrasolar X-ray source, Sco X-1, orders of magnitude stronger than astronomers believed might exist; (2) identification of a strong X-ray source with the Crab Nebula; (3) identification of Sco X-1 with a faint, peculiar optical object; (4) demonstration that X-ray stars are binary systems, each consisting of a collapsed object accreting matter from an ordinary star; (5) discovery of X-ray bursts; (6) discovery of exceedingly strong X-ray emission from active galaxies, quasars and clusters of galaxies; (7) demonstration that the principal X-ray source is a hot gas filling the space between galaxies.

BTEX exposures in an area impacted by industrial and mobile sources: Source attribution and impact of averaging time.

PubMed

Presto, Albert A; Dallmann, Timothy R; Gu, Peishi; Rao, Unnati

2016-04-01

The impacts of emissions plumes from major industrial sources on black carbon (BC) and BTEX (benzene, toluene, ethyl benzene, xylene isomers) exposures in communities located >10 km from the industrial source areas were identified with a combination of stationary measurements, source identification using positive matrix factorization (PMF), and dispersion modeling. The industrial emissions create multihour plume events of BC and BTEX at the measurement sites. PMF source apportionment, along with wind patterns, indicates that the observed pollutant plumes are the result of transport of industrial emissions under conditions of low boundary layer height. PMF indicates that industrial emissions contribute >50% of outdoor exposures of BC and BTEX species at the receptor sites. Dispersion modeling of BTEX emissions from known industrial sources predicts numerous overnight plumes and overall qualitative agreement with PMF analysis, but predicts industrial impacts at the measurement sites a factor of 10 lower than PMF. Nonetheless, exposures associated with pollutant plumes occur mostly at night, when residents are expected to be home but are perhaps unaware of the elevated exposure. Averaging data samples over long times typical of public health interventions (e.g., weekly or biweekly passive sampling) misapportions the exposure, reducing the impact of industrial plumes at the expense of traffic emissions, because the longer samples cannot resolve subdaily plumes. Suggestions are made for ways for future distributed pollutant mapping or intervention studies to incorporate high time resolution tools to better understand the potential impacts of industrial plumes. Emissions from industrial or other stationary sources can dominate air toxics exposures in communities both near the source and in downwind areas in the form of multihour plume events. Common measurement strategies that use highly aggregated samples, such as weekly or biweekly averages, are insensitive to such plume events and can lead to significant under apportionment of exposures from these sources.

Attributing Methane and Carbon Dioxide Emissions from Anthropogenic and Natural Sources Using AVIRIS-NG

NASA Astrophysics Data System (ADS)

Thorpe, A. K.; Frankenberg, C.; Thompson, D. R.; Duren, R. M.; Aubrey, A. D.; Bue, B. D.; Green, R. O.; Gerilowski, K.; Krings, T.; Borchardt, J.; Kort, E. A.; Sweeney, C.; Conley, S. A.; Roberts, D. A.; Dennison, P. E.; Ayasse, A.

2016-12-01

Imaging spectrometers like the next generation Airborne Visible/Infrared Imaging Spectrometer (AVIRIS-NG) can map large regions with the high spatial resolution necessary to resolve methane (CH4) and carbon dioxide (CO2) emissions. This capability is aided by real time detection and geolocation of gas plumes, permitting unambiguous identification of individual emission source locations and communication to ground teams for rapid follow up. We present results from AVIRIS-NG flight campaigns in the Four Corners region (Colorado and New Mexico) and the San Joaquin Valley (California). Over three hundred plumes were observed, reflecting emissions from anthropogenic and natural sources. Examples of plumes will be shown for a number of sources, including CH4 from well completions, gas processing plants, tanks, pipeline leaks, natural seeps, and CO2 from power plants. Despite these promising results, an imaging spectrometer built exclusively for quantitative mapping of gas plumes would have improved sensitivity compared to AVIRIS-NG. For example, an instrument providing a 1 nm spectral sampling (2,000-2,400 micron) would permit mapping CH4, CO2, H2O, CO, and N2O from more diffuse sources using both airborne and orbital platforms. The ability to identify emission sources offers the potential to constrain regional greenhouse gas budgets and improve partitioning between anthropogenic and natural emission sources. Because the CH4 lifetime is only about 9 years and CH4 has a Global Warming Potential 86 times that of CO2 for a 20 year time interval, mitigating these emissions is a particularly cost-effective approach to reduce overall atmospheric radiative forcing. Fig. 1. True color image subset with superimposed gas plumes showing concentrations in ppmm. Left: AVIRIS-NG observed CH4 plumes from natural gas processing plant extending over 500 m downwind of multiple emissions sources. Right: Multiple CO2 plumes observed from coal-fired power plant.

CONSTRAINING URBAN-TO-GLOBAL SCALE ESTIMATES OF BLACK CARBON DISTRIBUTIONS, SOURCES, REGIONAL CLIMATE IMPACTS, AND CO-BENEFIT METRICS WITH ADVANCED COUPLED DYNAMIC - CHEMICAL TRANSPORT - ADJOINT MODELS

EPA Science Inventory

This project will provide an unprecedented and much-needed identification and ranking of the sources of uncertainty in BC, its effects on climate, and the impacts of policy actions to reduce its impact on air quality and climate. The estimates of process and emissions uncertai...

Historical evolution of sources identification by means of Receptor Modeling in the Metropolitan Area of São Paulo, Brazil.

NASA Astrophysics Data System (ADS)

Miranda, R. M.; Andrade, M. D. F.; Marien, Y., Sr.

2017-12-01

The atmospheric aerosols sources have been identified in Sao Paulo since the 80´s with the use of receptor models. The Metropolitan Area of São Paulo (MASP) is a megacity with a population of 21 million, corresponding to more than 11% of the total population of Brazil. The first results for the identification of sources of particles were obtained with the application of Absolute Principal Component Analysis, Factor Analysis and Chemical Mass Balance. More recently the Positive Matrix Factorization has been used in combination with the other receptor models. With the improvement of the aerosol composition analytical determination (more elements and better resolution) the source identification has became more accurate. But, in spite of that, the main sources are the same for fine particles: vehicular emission, secondary formation and biomass burning. The large amount of biofuels used in the MASP makes this region an important example of the atmospheric chemistry of fossil fuel and biofuel emissions. The 7 million vehicles can run on gasohol, ethanol (95% ethanol + 5% gasoline) and biodiesel (mostly for trucks and buses). We have considered the Black Carbon as the tracer for diesel engines and biomass burning, being this last source associated not only with burning of sugar cane plantation and forest fires, but also with wood and charcoal used in restaurant and domestic cooking and residues burning. The responsibility of the vehicular emission to the fine particles has been maintained in approximately 50% of the mass. The soil resuspension was associated with 8% of the fine particles origin. We are presenting the data obtained from experiments performed from 1983 to 2014, not continuously and mainly performed in the winter time. It is a long period of data that is going to be considered. The previous results obtained with the application of PCA were compared to that obtained with PMF applied to the historical data collected at MASP, showing the evolution of the participation of mobile and biomass burning.

A comparison of PCA and PMF models for source identification of fugitive methane emissions

NASA Astrophysics Data System (ADS)

Assan, Sabina; Baudic, Alexia; Bsaibes, Sandy; Gros, Valerie; Ciais, Philippe; Staufer, Johannes; Robinson, Rod; Vogel, Felix

2017-04-01

Methane (CH_4) is a greenhouse gas with a global warming potential 28-32 times that of carbon dioxide (CO_2) on a 100 year period, and even greater on shorter timescales [Etminan, et al., 2016, Allen, 2014]. Thus, despite its relatively short life time and smaller emission quantities compared to CO_2, CH4 emissions contribute to approximately 20{%} of today's anthropogenic greenhouse gas warming [Kirschke et al., 2013]. Major anthropogenic sources include livestock (enteric fermentation), oil and gas production and distribution, landfills, and wastewater emissions [EPA, 2011]. Especially in densely populated areas multiple CH4 sources can be found in close vicinity. Thus, when measuring CH4 emissions at local scales it is necessary to distinguish between different CH4 source categories to effectively quantify the contribution of each sector and aid the implementation of greenhouse gas reduction strategies. To this end, source apportionment models can be used to aid the interpretation of spatial and temporal patterns in order to identify and characterise emission sources. The focus of this study is to evaluate two common linear receptor models, namely Principle Component Analysis (PCA) and Positive Matrix Factorisation (PMF) for CH4 source apportionment. The statistical models I will present combine continuous in-situ CH4 , C_2H_6, δ^1^3CH4 measured using a Cavity Ring Down Spectroscopy (CRDS) instrument [Assan et al. 2016] with volatile organic compound (VOC) observations performed using Gas Chromatography (GC) in order to explain the underlying variance of the data. The strengths and weaknesses of both models are identified for data collected in multi-source environments in the vicinity of four different types of sites; an agricultural farm with cattle, a natural gas compressor station, a wastewater treatment plant, and a pari-urban location in the Ile de France region impacted by various sources. To conclude, receptor model results to separate statistically the different sources from the variability of atmospheric observations are compared with an independent source identification method using stable methane isotopic analysis and simple CH_4/VOC ratios. Allen, D. T. (2014). Methane emissions from natural gas production and use: reconciling bottom-up and top-down measurements. Current Opinion in Chemical Engineering, 5, 78-83. Assan, S., Baudic, A., Guemri, A., Ciais, P., Gros, V., and Vogel, F. R.: Characterisation of interferences to in-situ observations of δ13CH4 and C2H6 when using a Cavity Ring Down Spectrometer at industrial sites, Atmos. Meas. Tech. Discuss., doi:10.5194/amt-2016-261, in review, 2016. Etminan, M., G. Myhre, E. J. Highwood and K. P. Shine (2016), Radiative forcing of carbon dioxide, methane, and nitrous oxide: A significant revision of the methane radiative forcing, Geophys. Res.Lett,43. Kirschke, S., Bousquet, P., Ciais, P., Saunois, M., Canadell, J. G., Dlugokencky, E. et al. (2013). Three decades of global methane sources and sinks. Nature Geoscience, 6(10), 813-823. U.S. Environmental Protection Agency's (U.S. EPA's). (2011) Global Anthropogenic Emissions of Non-CO2 Greenhouse Gases: 1990-2030. EPA 430-D-11-003

Improving source identification of Atlanta aerosol using temperature resolved carbon fractions in positive matrix factorization

NASA Astrophysics Data System (ADS)

Kim, Eugene; Hopke, Philip K.; Edgerton, Eric S.

Daily integrated PM 2.5 (particulate matter ⩽2.5 μm in aerodynamic diameter) composition data including eight individual carbon fractions collected at the Jefferson Street monitoring site in Atlanta were analyzed with positive matrix factorization (PMF). Particulate carbon was analyzed using the thermal optical reflectance method that divides carbon into four organic carbon (OC), pyrolized organic carbon (OP), and three elemental carbon (EC) fractions. A total of 529 samples and 28 variables were measured between August 1998 and August 2000. PMF identified 11 sources in this study: sulfate-rich secondary aerosol I (50%), on-road diesel emissions (11%), nitrate-rich secondary aerosol (9%), wood smoke (7%), gasoline vehicle (6%), sulfate-rich secondary aerosol II (6%), metal processing (3%), airborne soil (3%), railroad traffic (3%), cement kiln/carbon-rich (2%), and bus maintenance facility/highway traffic (2%). Differences from previous studies using only the traditional OC and EC data (J. Air Waste Manag. Assoc. 53(2003a)731; Atmos Environ. (2003b)) include four traffic-related combustion sources (gasoline vehicle, on-road diesel, railroad, and bus maintenance facility) containing carbon fractions whose abundances were different between the various sources. This study indicates that the temperature resolved fractional carbon data can be utilized to enhance source apportionment study, especially with respect to the separation of diesel emissions from gasoline vehicle sources. Conditional probability functions using surface wind data and identified source contributions aid the identifications of local point sources.

Radio and X-ray properties of the source G29.37+0.1 linked to HESS J1844-030

NASA Astrophysics Data System (ADS)

Castelletti, G.; Supan, L.; Petriella, A.; Giacani, E.; Joshi, B. C.

2017-06-01

Aims: We report on the first detailed multiwavelength study of the radio source G29.37+0.1, which is an as-yet-unclassified object linked to the very-high-energy γ-emitting source HESS J1844-030. The origin of the multiwavelength emission toward G29.37+0.1 has not been clarified so far, leaving open the question about the physical relationship between these sources. Methods: Using observations carried out with the Giant Metrewave Radio Telescope (GMRT), we performed high-quality full-synthesis imaging at 610 MHz of the field containing G29.37+0.1. The obtained data, combined with observations at 1400 MHz from The Multi-Array Galactic Plane Imaging Survey (MAGPIS) were used to investigate in detail the properties of its radio emission. Additionally, we reprocessed archival data obtained with the XMM-Newton and Chandra observatories in order to get a multiwavelength view of this unusual source. Results: The radio source G29.37+0.1 mainly consists of a bright twisted structure, named the S-shaped feature. The high sensitivity of the new GMRT observations allowed the identification of potential lobes, jets, and a nuclear central region in the S-shaped morphology of G29.37+0.1. We also highlight the detection of diffuse and low surface brightness emission enveloping the brightest emitting regions. The brightest emission in G29.37+0.1 has a radio synchrotron spectral index α = 0.59 ± 0.09. Variations in the spectral behaviour are observed across the whole radio source with the flattest spectral features in the central nuclear and jets components (α 0.3). These results lead us to conclude that the brightest radio emission from G29.37+0.1 likely represents a newly recognized radio galaxy. The identification of optical and infrared counterparts to the emission arising from the core of G29.37+0.1 strengthens our interpretation of an extragalactic origin of the radio emission. We performed several tests to explain the physical mechanism responsible for the observed X-ray emission, which appears overlapping the northeastern part of the radio emission. Our spectral analysis demonstrated that a non-thermal origin for the X-ray emission compatible with a pulsar wind nebula is quite possible. The analysis of the spatial distribution of the CO gas revealed the presence of a complex of molecular clouds located in projection adjacent to the radio halo emission and probably interacting with it. We propose that the faint halo represents a composite supernova remnant with a pulsar powered component given by the diffuse X-ray emission superimposed along the line of sight to the radio galaxy. Further broadband observations of HESS J1844-030 are needed to disentangle its origin, although its shape and position suggest an extragalactic origin connected to G29.37+0.1. The reduced GMRT image (FITS file) is only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/602/A31

Identification of Dust Source Regions at High-Resolution and Dynamics of Dust Source Mask over Southwest United States Using Remote Sensing Data

NASA Astrophysics Data System (ADS)

Sprigg, W. A.; Sahoo, S.; Prasad, A. K.; Venkatesh, A. S.; Vukovic, A.; Nickovic, S.

2015-12-01

Identification and evaluation of sources of aeolian mineral dust is a critical task in the simulation of dust. Recently, time series of space based multi-sensor satellite images have been used to identify and monitor changes in the land surface characteristics. Modeling of windblown dust requires precise delineation of mineral dust source and its strength that varies over a region as well as seasonal and inter-annual variability due to changes in land use and land cover. Southwest USA is one of the major dust emission prone zone in North American continent where dust is generated from low lying dried-up areas with bare ground surface and they may be scattered or appear as point sources on high resolution satellite images. In the current research, various satellite derived variables have been integrated to produce a high-resolution dust source mask, at grid size of 250 m, using data such as digital elevation model, surface reflectance, vegetation cover, land cover class, and surface wetness. Previous dust source models have been adopted to produce a multi-parameter dust source mask using data from satellites such as Terra (Moderate Resolution Imaging Spectroradiometer - MODIS), and Landsat. The dust source mask model captures the topographically low regions with bare soil surface, dried-up river plains, and lakes which form important source of dust in southwest USA. The study region is also one of the hottest regions of USA where surface dryness, land use (agricultural use), and vegetation cover changes significantly leading to major changes in the areal coverage of potential dust source regions. A dynamic high resolution dust source mask have been produced to address intra-annual change in the aerial extent of bare dry surfaces. Time series of satellite derived data have been used to create dynamic dust source masks. A new dust source mask at 16 day interval allows enhanced detection of potential dust source regions that can be employed in the dust emission and transport pathways models for better estimation of emission of dust during dust storms, particulate air pollution, public health risk assessment tools and decision support systems.

Discovery of a Hand X-Ray Source, SAX J0635+0533, in the Error Box of the Gamma-Ray Source 2EG J0635+0521

NASA Technical Reports Server (NTRS)

Kaaret, P.; Piraino, S.; Halpern, Jules P.; Eracleous, M.; Oliversen, Ronald (Technical Monitor)

2001-01-01

We have discovered an X-ray source, SAX J0635+0533, with a hard spectrum within the error box of the GeV gamma-ray source in Monoceros, 2EG J0635+0521. The unabsorbed flux from the source is 1.2 x 10(exp -11) ergs /sq cm s in the 2-10 keV band. The X-ray spectrum is consistent with a simple power-law model with absorption. The photon index is 1.50 +/- 0.08, and we detect emission out to 40 keV. Optical observations identify a counterpart with a V magnitude of 12.8. The counterpart has broad emission lines and the colors of an early B-type star. If the identification of the X-ray/optical source with the gamma-ray source is correct, then the source would be a gamma-ray-emitting X-ray binary.

Sources and properties of non-exhaust particulate matter from road traffic: a review.

PubMed

Thorpe, Alistair; Harrison, Roy M

2008-08-01

While emissions control regulation has led to a substantial reduction in exhaust emissions from road traffic, currently non-exhaust emissions from road vehicles are unabated. These include particles from brake wear, tyre wear, road surface abrasion and resuspension in the wake of passing traffic. Quantification of the magnitude of such emissions is problematic both in the laboratory and the field and the latter depends heavily upon a knowledge of the physical and chemical properties of non-exhaust particles. This review looks at each source in turn, reviewing the available information on the source materials and particles derived from them in laboratory studies. In a final section, some of the key publications dealing with measurements in road tunnels and the roadside environment are reviewed. It is concluded that with the exception of brake dust particles which may be identified from their copper (Cu) and antimony (Sb) content, unequivocal identification of particles from other sources is likely to prove extremely difficult, either because of the lack of suitable tracer elements or compounds, or because of the interactions between sources prior to the emission process. Even in the case of brake dust, problems will arise in distinguishing directly emitted particles from those arising from resuspension of deposited brake dust from the road surface, or that derived from entrainment of polluted roadside soils, either directly or as a component of road surface dust.

New directions: Beyond sulphur, vanadium and nickel - About source apportionment of ship emissions in emission control areas

NASA Astrophysics Data System (ADS)

Czech, Hendryk; Schnelle-Kreis, Jürgen; Streibel, Thorsten; Zimmermann, Ralf

2017-08-01

During the oil crises of the 70s and the associated increase of the oil price, the usage of marine fuels shifted from middle distillates of the crude oil refinery, such as marine diesel oil (MDO) or marine gas oil (MGO), towards cheaper heavy fuel oils (HFO), or also called residual fuel oil. The latter refers to the vacuum residue of the crude oil refinery blended by lighter refinery products, such as kerosene, to meet a certain maximum viscosity. Those HFOs are rich in sulphur and heavy metals which end up as significant constituents in emitted fine particulate matter (PM2.5) after the combustion. Especially for harbour cities or highly frequented ship traffic routes, HFO-derived PM2.5 has been identified as a globally important perpetrator of increased mortality by cardiopulmonary diseases and lung cancer (e.g. Corbett et al., 2007). However, the emitted hazardous species provide reliable markers to assess the contribution of this emission source to air pollution in source apportionment studies. Such studies are often performed utilising positive matrix factorisation, whose score matrix can be interpreted as temporal contribution of k identified emission sources and factors represent the k corresponding emission profiles. If one of the k factors contains moderate to high amounts of sulphate, vanadium and nickel with a high ratio of the two latter ones, the ship identification was unambiguous (e.g. Viana et al., 2009). Even more sensitive towards emission profiles are receptor models such as chemical mass balance, which require detailed prior knowledge about the assumed emission sources (Jeong et al., 2017).

ENDOCRINE DISRUPTORS FROM COMBUSTION AND VEHICULAR EMISSIONS: IDENTIFICATION AND SOURCE NOMINATION

EPA Science Inventory

During the last decade, concerns have been raised regarding the possible harmful effects of exposure to certain chemicals that are capable of modulating or disrupting the function of the endocrine system. These chemicals, which are referred to as endocrine disrupting chemicals (E...

ENDOCRINE DISRUPTORS FROM COMBUSTION AND VEHICULAR EMISSIONS: IDENTIFICATION AND SOURCE NOMINATION. (R828190)

EPA Science Inventory

The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

Use of UV Sources for Detection and Identification of Explosives

NASA Technical Reports Server (NTRS)

Hug, William; Reid, Ray; Bhartia, Rohit; Lane, Arthur

2009-01-01

Measurement of Raman and native fluorescence emission using ultraviolet (UV) sources (<400 nm) on targeted materials is suitable for both sensitive detection and accurate identification of explosive materials. When the UV emission data are analyzed using a combination of Principal Component Analysis (PCA) and cluster analysis, chemicals and biological samples can be differentiated based on the geometric arrangement of molecules, the number of repeating aromatic rings, associated functional groups (nitrogen, sulfur, hydroxyl, and methyl), microbial life cycles (spores vs. vegetative cells), and the number of conjugated bonds. Explosive materials can be separated from one another as well as from a range of possible background materials, which includes microbes, car doors, motor oil, and fingerprints on car doors, etc. Many explosives are comprised of similar atomic constituents found in potential background samples such as fingerprint oils/skin, motor oil, and soil. This technique is sensitive to chemical bonds between the elements that lead to the discriminating separability between backgrounds and explosive materials.

Pattern recognition methods and air pollution source identification. [based on wind direction

NASA Technical Reports Server (NTRS)

Leibecki, H. F.; King, R. B.

1978-01-01

Directional air samplers, used for resolving suspended particulate matter on the basis of time and wind direction were used to assess the feasibility of characterizing and identifying emission source types in urban multisource environments. Filters were evaluated for 16 elements and X-ray fluorescence methods yielded elemental concentrations for direction, day, and the interaction of direction and day. Large numbers of samples are necessary to compensate for large day-to-day variations caused by wind perturbations and/or source changes.

Circinus X-1: a Laboratory for Studying the Accretion Phenomenon in Compact Binary X-Ray Sources. Ph.D. Thesis - Maryland Univ.

NASA Technical Reports Server (NTRS)

Robinson-Saba, J. L.

1983-01-01

Observations of the binary X-ray source Circinus X-1 provide samples of a range of spectral and temporal behavior whose variety is thought to reflect a broad continuum of accretion conditions in an eccentric binary system. The data support an identification of three or more X-ray spectral components, probably associated with distinct emission regions.

Fermi Large Area Telescope First Source Catalog

DOE PAGES

Abdo, A. A.; Ackermann, M.; Ajello, M.; ...

2010-05-25

Here, we present a catalog of high-energy gamma-ray sources detected by the Large Area Telescope (LAT), the primary science instrument on the Fermi Gamma-ray Space Telescope (Fermi), during the first 11 months of the science phase of the mission, which began on 2008 August 4. The First Fermi-LAT catalog (1FGL) contains 1451 sources detected and characterized in the 100 MeV to 100 GeV range. Source detection was based on the average flux over the 11 month period, and the threshold likelihood Test Statistic is 25, corresponding to a significance of just over 4σ. The 1FGL catalog includes source location regions,more » defined in terms of elliptical fits to the 95% confidence regions and power-law spectral fits as well as flux measurements in five energy bands for each source. In addition, monthly light curves are provided. Using a protocol defined before launch we have tested for several populations of gamma-ray sources among the sources in the catalog. For individual LAT-detected sources we provide firm identifications or plausible associations with sources in other astronomical catalogs. Identifications are based on correlated variability with counterparts at other wavelengths, or on spin or orbital periodicity. For the catalogs and association criteria that we have selected, 630 of the sources are unassociated. In conclusion, care was taken to characterize the sensitivity of the results to the model of interstellar diffuse gamma-ray emission used to model the bright foreground, with the result that 161 sources at low Galactic latitudes and toward bright local interstellar clouds are flagged as having properties that are strongly dependent on the model or as potentially being due to incorrectly modeled structure in the Galactic diffuse emission.« less

EX56a study of extended X-ray emission around isolated galaxies EX56b identification and spectra of bright X-ray sources at high galactic latitude

NASA Technical Reports Server (NTRS)

Schwartz, Daniel A.

1987-01-01

The EXOSAT observations confirmed the identification and extended nature of PKS 2345-35. It gave a good 2 to 10 keV X-ray spectrum and a detailed spatial profile indicating asymmetry of the structure. In the high galactic latitidue investigation, the BL Lac object identified with the HEAO-1 source 1430+423 was detected, and the first X-ray spectrum was obtained. Several simulataneous observations of H0323+022 were obtained over a broad range of electromagnetic spectrum. Studies of luminous active galactic nuclei have given significant information on the spectrum of the quasar PKS 0558-504. In a study of Southern sky cataclysmic variables, the EXOSAT was used to determine the X-ray spectrum and search for periodicities in two objects. Studies of complete identifications have revealed that X-ray sources in two high galactic latitude fields are stars, and therefore are to be excluded from the Piccinotti extragalactic sample. Only one Piccinotti source remains to be identified.

Identification and elucidation of anthropogenic source contribution in PM10 pollutant: Insight gain from dispersion and receptor models.

PubMed

Roy, Debananda; Singh, Gurdeep; Yadav, Pankaj

2016-10-01

Source apportionment study of PM 10 (Particulate Matter) in a critically polluted area of Jharia coalfield, India has been carried out using Dispersion model, Principle Component Analysis (PCA) and Chemical Mass Balance (CMB) techniques. Dispersion model Atmospheric Dispersion Model (AERMOD) was introduced to simplify the complexity of sources in Jharia coalfield. PCA and CMB analysis indicates that monitoring stations near the mining area were mainly affected by the emission from open coal mining and its associated activities such as coal transportation, loading and unloading of coal. Mine fire emission also contributed a considerable amount of particulate matters in monitoring stations. Locations in the city area were mostly affected by vehicular, Liquid Petroleum Gas (LPG) & Diesel Generator (DG) set emissions, residential, and commercial activities. The experimental data sampling and their analysis could aid understanding how dispersion based model technique along with receptor model based concept can be strategically used for quantitative analysis of Natural and Anthropogenic sources of PM 10 . Copyright © 2016. Published by Elsevier B.V.

HEAO Science Symposium

NASA Technical Reports Server (NTRS)

Dailey, C. (Editor); Johnson, W. (Editor)

1979-01-01

Scientific results from the early analysis of data from the HEAO 1 mission are presented. Development of astronomical catalogs and maps, X-ray variability, extragalactic astronomy, X-ray iron line emission, and optical identification and spectroscopy of X-ray sources are among the topics discussed. Results from HEAO 2 imaging and nonimaging instruments are included.

40 CFR 49.139 - Rule for non-Title V operating permits.

Code of Federal Regulations, 2011 CFR

2011-07-01

... the air pollution source, the Tribal governing body, and the Tribal, State, and local air pollution... limitation. (C) A description of the production processes and a related flow chart. (D) Identification of...; (ii) Mass balance calculations; (iii) Published, verifiable emission factors that are applicable to...

40 CFR 49.139 - Rule for non-Title V operating permits.

Code of Federal Regulations, 2013 CFR

2013-07-01

... the air pollution source, the Tribal governing body, and the Tribal, State, and local air pollution... limitation. (C) A description of the production processes and a related flow chart. (D) Identification of...; (ii) Mass balance calculations; (iii) Published, verifiable emission factors that are applicable to...

40 CFR 49.139 - Rule for non-Title V operating permits.

Code of Federal Regulations, 2014 CFR

2014-07-01

... the air pollution source, the Tribal governing body, and the Tribal, State, and local air pollution... limitation. (C) A description of the production processes and a related flow chart. (D) Identification of...; (ii) Mass balance calculations; (iii) Published, verifiable emission factors that are applicable to...

40 CFR 49.139 - Rule for non-Title V operating permits.

Code of Federal Regulations, 2012 CFR

2012-07-01

... the air pollution source, the Tribal governing body, and the Tribal, State, and local air pollution... limitation. (C) A description of the production processes and a related flow chart. (D) Identification of...; (ii) Mass balance calculations; (iii) Published, verifiable emission factors that are applicable to...

40 CFR 52.2720 - Identification of plan.

Code of Federal Regulations, 2010 CFR

2010-07-01

...) Emission limitation for one source in the Ponce Air Basin was submitted on March 26, 1976, by the... schedules submitted on March 13, 1974, by the Puerto Rico Environmental Quality Board. (13) Information on procedures followed in adoption of compliance schedules submitted on March 15, 1974, by the Puerto Rico...

Airborne DOAS retrievals of methane, carbon dioxide, and water vapor concentrations at high spatial resolution: application to AVIRIS-NG

NASA Astrophysics Data System (ADS)

Thorpe, Andrew K.; Frankenberg, Christian; Thompson, David R.; Duren, Riley M.; Aubrey, Andrew D.; Bue, Brian D.; Green, Robert O.; Gerilowski, Konstantin; Krings, Thomas; Borchardt, Jakob; Kort, Eric A.; Sweeney, Colm; Conley, Stephen; Roberts, Dar A.; Dennison, Philip E.

2017-10-01

At local scales, emissions of methane and carbon dioxide are highly uncertain. Localized sources of both trace gases can create strong local gradients in its columnar abundance, which can be discerned using absorption spectroscopy at high spatial resolution. In a previous study, more than 250 methane plumes were observed in the San Juan Basin near Four Corners during April 2015 using the next-generation Airborne Visible/Infrared Imaging Spectrometer (AVIRIS-NG) and a linearized matched filter. For the first time, we apply the iterative maximum a posteriori differential optical absorption spectroscopy (IMAP-DOAS) method to AVIRIS-NG data and generate gas concentration maps for methane, carbon dioxide, and water vapor plumes. This demonstrates a comprehensive greenhouse gas monitoring capability that targets methane and carbon dioxide, the two dominant anthropogenic climate-forcing agents. Water vapor results indicate the ability of these retrievals to distinguish between methane and water vapor despite spectral interference in the shortwave infrared. We focus on selected cases from anthropogenic and natural sources, including emissions from mine ventilation shafts, a gas processing plant, tank, pipeline leak, and natural seep. In addition, carbon dioxide emissions were mapped from the flue-gas stacks of two coal-fired power plants and a water vapor plume was observed from the combined sources of cooling towers and cooling ponds. Observed plumes were consistent with known and suspected emission sources verified by the true color AVIRIS-NG scenes and higher-resolution Google Earth imagery. Real-time detection and geolocation of methane plumes by AVIRIS-NG provided unambiguous identification of individual emission source locations and communication to a ground team for rapid follow-up. This permitted verification of a number of methane emission sources using a thermal camera, including a tank and buried natural gas pipeline.

A search for soft X-ray emission from red-giant coronae

NASA Technical Reports Server (NTRS)

Margon, B.; Mason, K. O.; Sanford, P. W.

1974-01-01

Hills has pointed out that if red-giant coronae are weak sources of soft X-rays, then the problems of the identification of the local component of the soft X-ray background and the observed lack of gas in globular clusters may be simultaneously resolved. Using instrumentation aboard OAO Copernicus, we have searched unsuccessfully for emission in the 10-100 A band from four nearby red giants. In all cases, our upper limits are of the order of the minimum theoretically predicted fluxes.

Toward a better understanding and quantification of methane emissions from shale gas development

PubMed Central

Caulton, Dana R.; Shepson, Paul B.; Santoro, Renee L.; Sparks, Jed P.; Howarth, Robert W.; Ingraffea, Anthony R.; Cambaliza, Maria O. L.; Sweeney, Colm; Karion, Anna; Davis, Kenneth J.; Stirm, Brian H.; Montzka, Stephen A.; Miller, Ben R.

2014-01-01

The identification and quantification of methane emissions from natural gas production has become increasingly important owing to the increase in the natural gas component of the energy sector. An instrumented aircraft platform was used to identify large sources of methane and quantify emission rates in southwestern PA in June 2012. A large regional flux, 2.0–14 g CH4 s−1 km−2, was quantified for a ∼2,800-km2 area, which did not differ statistically from a bottom-up inventory, 2.3–4.6 g CH4 s−1 km−2. Large emissions averaging 34 g CH4/s per well were observed from seven well pads determined to be in the drilling phase, 2 to 3 orders of magnitude greater than US Environmental Protection Agency estimates for this operational phase. The emissions from these well pads, representing ∼1% of the total number of wells, account for 4–30% of the observed regional flux. More work is needed to determine all of the sources of methane emissions from natural gas production, to ascertain why these emissions occur and to evaluate their climate and atmospheric chemistry impacts. PMID:24733927

Toward a better understanding and quantification of methane emissions from shale gas development.

PubMed

Caulton, Dana R; Shepson, Paul B; Santoro, Renee L; Sparks, Jed P; Howarth, Robert W; Ingraffea, Anthony R; Cambaliza, Maria O L; Sweeney, Colm; Karion, Anna; Davis, Kenneth J; Stirm, Brian H; Montzka, Stephen A; Miller, Ben R

2014-04-29

The identification and quantification of methane emissions from natural gas production has become increasingly important owing to the increase in the natural gas component of the energy sector. An instrumented aircraft platform was used to identify large sources of methane and quantify emission rates in southwestern PA in June 2012. A large regional flux, 2.0-14 g CH4 s(-1) km(-2), was quantified for a ∼ 2,800-km(2) area, which did not differ statistically from a bottom-up inventory, 2.3-4.6 g CH4 s(-1) km(-2). Large emissions averaging 34 g CH4/s per well were observed from seven well pads determined to be in the drilling phase, 2 to 3 orders of magnitude greater than US Environmental Protection Agency estimates for this operational phase. The emissions from these well pads, representing ∼ 1% of the total number of wells, account for 4-30% of the observed regional flux. More work is needed to determine all of the sources of methane emissions from natural gas production, to ascertain why these emissions occur and to evaluate their climate and atmospheric chemistry impacts.

Identification of the Hard X-Ray Source Dominating the E > 25 keV Emission of the Nearby Galaxy M31

NASA Technical Reports Server (NTRS)

Yukita, M.; Ptak, A.; Hornschemeier, A. E.; Wik, D.; Maccarone, T.J.; Pottschmidt, Katja; Zezas, A.; Antoniou, V.; Ballhausen, R.; Lehmer, B.D.;

Identification of the Hard X-Ray Source Dominating the E > 25 keV Emission of the Nearby Galaxy M31

NASA Technical Reports Server (NTRS)

Yukita, M.; Ptak, A.; Hornschemeier, A. E.; Wik, D.; Maccarone, T. J.; Pottschmidt, K.; Zezas, A.; Antoniou, V.; Ballhausen, R.; Lehmer, B. D.;

[Spatial heterogeneity and classified control of agricultural non-point source pollution in Huaihe River Basin].

PubMed

Zhou, Liang; Xu, Jian-Gang; Sun, Dong-Qi; Ni, Tian-Hua

2013-02-01

Agricultural non-point source pollution is of importance in river deterioration. Thus identifying and concentrated controlling the key source-areas are the most effective approaches for non-point source pollution control. This study adopts inventory method to analysis four kinds of pollution sources and their emissions intensity of the chemical oxygen demand (COD), total nitrogen (TN), and total phosphorus (TP) in 173 counties (cities, districts) in Huaihe River Basin. The four pollution sources include livestock breeding, rural life, farmland cultivation, aquacultures. The paper mainly addresses identification of non-point polluted sensitivity areas, key pollution sources and its spatial distribution characteristics through cluster, sensitivity evaluation and spatial analysis. A geographic information system (GIS) and SPSS were used to carry out this study. The results show that: the COD, TN and TP emissions of agricultural non-point sources were 206.74 x 10(4) t, 66.49 x 10(4) t, 8.74 x 10(4) t separately in Huaihe River Basin in 2009; the emission intensity were 7.69, 2.47, 0.32 t.hm-2; the proportions of COD, TN, TP emissions were 73%, 24%, 3%. The paper achieves that: the major pollution source of COD, TN and TP was livestock breeding and rural life; the sensitivity areas and priority pollution control areas among the river basin of non-point source pollution are some sub-basins of the upper branches in Huaihe River, such as Shahe River, Yinghe River, Beiru River, Jialu River and Qingyi River; livestock breeding is the key pollution source in the priority pollution control areas. Finally, the paper concludes that pollution type of rural life has the highest pollution contribution rate, while comprehensive pollution is one type which is hard to control.

Small plasma focus as neutron pulsed source for nuclides identification

NASA Astrophysics Data System (ADS)

Milanese, M.; Niedbalski, J.; Moroso, R.; Barbaglia, M.; Mayer, R.; Castillo, F.; Guichón, S.

2013-10-01

In this paper, we present preliminary results on the feasibility of employing a low energy (2 kJ, 31 kV) plasma focus device as a portable source of pulsed neutron beams (2.45 MeV) generated by nuclear fusion reactions D-D, for the "in situ" analysis of substances by nuclear activation. This source has the relevant advantage of being pulsed at requirement, transportable, not permanently radioactive, without radioactive waste, cheap, among others. We prove the feasibility of using this source showing several spectra of the characteristic emission line for manganese, gold, lead, and silver.

Small plasma focus as neutron pulsed source for nuclides identification.

PubMed

Milanese, M; Niedbalski, J; Moroso, R; Barbaglia, M; Mayer, R; Castillo, F; Guichón, S

2013-10-01

In this paper, we present preliminary results on the feasibility of employing a low energy (2 kJ, 31 kV) plasma focus device as a portable source of pulsed neutron beams (2.45 MeV) generated by nuclear fusion reactions D-D, for the "in situ" analysis of substances by nuclear activation. This source has the relevant advantage of being pulsed at requirement, transportable, not permanently radioactive, without radioactive waste, cheap, among others. We prove the feasibility of using this source showing several spectra of the characteristic emission line for manganese, gold, lead, and silver.

Source identification of PM2.5 at a port and an adjacent urban site in a coastal city of China: Impact of ship emissions and port activities.

PubMed

Xu, Lingling; Jiao, Ling; Hong, Zhenyu; Zhang, Yanru; Du, Wenjiao; Wu, Xin; Chen, Yanting; Deng, Junjun; Hong, Youwei; Chen, Jinsheng

2018-09-01

Daily PM 2.5 samples were collected simultaneously at an urban site (UB) and a nearby port-industrial site (PI) on the coast of southeastern China from April 2015 to January 2016. The PM 2.5 mass concentration at the PI (51.9μgm -3 ) was significantly higher than that at the UB. The V concentration at the PI was also significantly higher and well-correlated to the urban value, which suggests that shipping emissions had a significant impact on the PI and, to a lesser extent, on the urban area. A positive matrix factorization (PMF) analysis showed that secondary aerosols were the dominant contribution of PM 2.5 at both sites (36.4% at the PI and 27.2% at the UB), while the contribution of industry and ship emissions identified by V, Mn, and Ba at the PI (26.1%) were double those at the UB. The difference in each source contribution among the trajectory clusters that included significant differences and insignificant differences from the UB to the PI provided insight into the role of local impacts. With regards to the UB, local potential sources play important roles in industry and ship emissions, traffic emissions, fugitive dust, and in their contributions to secondary aerosols. A conditional probability function further revealed that the ship emissions and port activities distributed in the NE, E, and SSE wind sectors were responsible for the source contributions of industry and ship emissions and secondary aerosols at the UB. This study provides an example of investigating the impact of ship emissions and port activities on the surrounding air environment using land-based measurements. Copyright © 2018 Elsevier B.V. All rights reserved.

Methane sources in Hong Kong - identification by mobile measurement and isotopic analysis

NASA Astrophysics Data System (ADS)

Fisher, Rebecca; Brownlow, Rebecca; Lowry, David; Lanoisellé, Mathias; Nisbet, Euan

2017-04-01

Hong Kong (22.4°N, 114.1°E) has a wide variety of natural and anthropogenic sources of methane within a small densely populated area (1106 km2, population ˜7.3 million). These include emissions from important source categories that have previously been poorly studied in tropical regions such as agriculture and wetlands. According to inventories (EDGAR v.4.2) anthropogenic methane emissions are mainly from solid waste disposal, wastewater disposal and fugitive leaks from oil and gas. Methane mole fraction was mapped out across Hong Kong during a mobile measurement campaign in July 2016. This technique allows rapid detection of the locations of large methane emissions which may focus targets for efforts to reduce emissions. Methane is mostly emitted from large point sources, with highest concentrations measured close to active landfill sites, sewage works and a gas processing plant. Air samples were collected close to sources (landfills, sewage works, gas processing plant, wetland, rice, traffic, cows and water buffalo) and analysed by mass spectrometry to determine the δ13C isotopic signatures to extend the database of δ13C isotopic signatures of methane from tropical regions. Isotopic signatures of methane sources in Hong Kong range from -70 ‰ (cows) to -37 ‰ (gas processing). Regular sampling of air for methane mole fraction and δ13C has recently begun at the Swire Institute of Marine Science, situated at Cape d'Aguilar in the southeast of Hong Kong Island. This station receives air from important source regions: southerly marine air from the South China Sea in summer and northerly continental air in winter and measurements will allow an integrated assessment of emissions from the wider region.

40 CFR 52.2320 - Identification of plan

Code of Federal Regulations, 2014 CFR

2014-07-01

... contaminant source,” “air pollution,” “allowable emissions,” “ambient air,” “best available control technology..., Kennecott Utah Copper Utah Power Plant AO DAQE-433-94 dated May 27, 1994, Hill Air Force Base (HAFB) AO DAQE... 52.2320 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED...

IDENTIFICATION OF SOURCES AND ESTIMATION OF EMISSION PROFILES FROM HIGHLY TIME-RESOLVED POLLUTANT MEASUREMENTS IN TAMPA, FL

EPA Science Inventory

Aerosol slurry samples were collected at 30-min intervals for sequential 1-month periods at each of two sites (Sydney and "Dairy") in the Tampa Bay area during the 2002 Bay Regional Atmospheric Chemistry Experiment using the University of Maryland Semicontinuous Elements in Aeros...

Image digitising and analysis of outflows from young stars

NASA Astrophysics Data System (ADS)

Zealey, W. J.; Mader, S. L.

1997-08-01

We present IIIaJ, IIIaF and IVN band images of Herbig-Haro objects digitised from the ESO/SERC Southern Sky Survey plates. These form part of a digital image database of southern HH objects, which allows the identification of emission and reflection nebulosity and the location of the obscured sources of outflows.

Two methods for transmission line simulation model creation based on time domain measurements

NASA Astrophysics Data System (ADS)

Rinas, D.; Frei, S.

2011-07-01

The emission from transmission lines plays an important role in the electromagnetic compatibility of automotive electronic systems. In a frequency range below 200 MHz radiation from cables is often the dominant emission factor. In higher frequency ranges radiation from PCBs and their housing becomes more relevant. Main sources for this emission are the conducting traces. The established field measurement methods according CISPR 25 for evaluation of emissions suffer from the need to use large anechoic chambers. Furthermore measurement data can not be used for simulation model creation in order to compute the overall fields radiated from a car. In this paper a method to determine the far-fields and a simulation model of radiating transmission lines, esp. cable bundles and conducting traces on planar structures, is proposed. The method measures the electromagnetic near-field above the test object. Measurements are done in time domain in order to get phase information and to reduce measurement time. On the basis of near-field data equivalent source identification can be done. Considering correlations between sources along each conductive structure in model creation process, the model accuracy increases and computational costs can be reduced.

PM₁₀ and PM₂.₅ sources at an insular location in the western Mediterranean by using source apportionment techniques.

PubMed

Pey, Jorge; Alastuey, Andrés; Querol, Xavier

2013-07-01

PM₁₀ and PM₂.₅ chemical composition has been determined at a suburban insular site in the Balearic Islands (Spain) during almost one and a half year. As a result, 200 samples with more than 50 chemical parameters analyzed have been obtained. The whole database has been analyzed by two receptor modelling techniques (Principal Component Analysis and Positive Matrix Factorisation) in order to identify the main PM sources. After that, regression analyses with respect to the PM mass concentrations were conducted to quantify the daily contributions of each source. Four common sources were identified by both receptor models: secondary nitrate coupled with vehicular emissions, secondary sulphate influenced by fuel-oil combustion, aged marine aerosols and mineral dust. In addition, PCA isolated harbour emissions and a mixed anthropogenic factor containing industrial emissions; whereas PMF isolated an additional mineral factor interpreted as road dust+harbour emissions, and a vehicular abrasion products factor. The use of both methodologies appeared complementary. Nevertheless, PMF sources by themselves were better differentiated. Besides these receptor models, a specific methodology to quantify African dust was also applied. The combination of these three source apportionment tools allowed the identification of 8 sources, being 4 of them mineral (African, regional, urban and harbour dusts). As a summary, 29% of PM₁₀ was attributed to natural sources (African dust, regional dust and sea spray), whereas the proportion diminished to 11% in PM₂.₅. Furthermore, the secondary sulphate source, which accounted for about 22 and 32% of PM₁₀ and PM₂.₅, is strongly linked to the aged polluted air masses residing over the western Mediterranean in the warm period. Copyright © 2013 Elsevier B.V. All rights reserved.

Identification of brake wear particles and derivation of a quantitative tracer for brake dust at a major road

NASA Astrophysics Data System (ADS)

Gietl, Johanna K.; Lawrence, Roy; Thorpe, Alistair J.; Harrison, Roy M.

2010-01-01

Traffic-generated air pollutant emissions can be classified into exhaust and non-exhaust emissions. Increased attention is focussing on non-exhaust emissions as exhaust emissions are progressively limited by regulations. To characterise metal-rich emission from abrasion processes, size-segregated analysis of atmospheric aerosol particles sampled with micro-orifice uniform deposit impactors (MOUDI) in March 2007 in London was performed. The samples were collected at a roadside and a background site and were analysed for Al, Ba, Cu, Fe, Sb, Ti, V, Zn, Ca 2+, K +, Mg 2+, Na +, and NH 4+. Most components showed a clear roadside increment, which was evident as a higher mass concentration and a change in the size distribution. In particular, Fe, Cu, Ba, and Sb correlated highly, indicative of a common traffic-related source. Using complementary information on the fleet composition, vehicle number and average speed, the brake wear emission was calculated using the EMEP/CORINAIR emission database. The total PM 10 and barium emission of the traffic was determined by ratio to NO x whose source strength was estimated from published emission factors. Barium was found to comprise 1.1% of brake wear (PM 10) particles from the traffic fleet as a whole, allowing its use as a quantitative tracer of brake wear emissions at other traffic-influenced sites.

Urban air quality in a mid-size city - PM2.5 composition, sources and identification of impact areas: From local to long range contributions

NASA Astrophysics Data System (ADS)

Squizzato, Stefania; Cazzaro, Marta; Innocente, Elena; Visin, Flavia; Hopke, Philip K.; Rampazzo, Giancarlo

2017-04-01

Urban air quality represents a major public health burden and is a long-standing concern to European citizens. Combustion processes and traffic-related emissions represent the main primary particulate matter (PM) sources in urban areas. Other sources can also affect air quality (e.g., secondary aerosol, industrial) depending on the characteristics of the study area. Thus, the identification and the apportionment of all sources is of crucial importance to make effective corrective decisions within environmental policies. The aim of this study is to evaluate the impacts of different emissions sources on PM2.5 concentrations and compositions in a mid-size city in the Po Valley (Treviso, Italy). Data have been analyzed to highlight compositional differences (elements and major inorganic ions), to determine PM2.5 sources and their contributions, and to evaluate the influence of air mass movements. Non-parametric tests, positive matrix factorization (PMF), conditional bivariate probability function (CBPF), and concentration weighted trajectory (CWT) have been used in a multi-chemometrics approach to understand the areal-scale (proximate, local, long-range) where different sources act on PM2.5 levels and composition. Results identified three levels of scale from which the pollution arose: (i) a proximate local scale (close to the sampling site) for traffic non-exhaust and resuspended dust sources; (ii) a local urban scale (including both sampling site and areas close to them) for combustion and industrial; and (iii) a regional scale characterized by ammonium nitrate and ammonium sulfate. This approach and results can help to develop and adopt better air quality policy action.

Receptor modeling for source apportionment of polycyclic aromatic hydrocarbons in urban atmosphere.

PubMed

Singh, Kunwar P; Malik, Amrita; Kumar, Ranjan; Saxena, Puneet; Sinha, Sarita

2008-01-01

This study reports source apportionment of polycyclic aromatic hydrocarbons (PAHs) in particulate depositions on vegetation foliages near highway in the urban environment of Lucknow city (India) using the principal components analysis/absolute principal components scores (PCA/APCS) receptor modeling approach. The multivariate method enables identification of major PAHs sources along with their quantitative contributions with respect to individual PAH. The PCA identified three major sources of PAHs viz. combustion, vehicular emissions, and diesel based activities. The PCA/APCS receptor modeling approach revealed that the combustion sources (natural gas, wood, coal/coke, biomass) contributed 19-97% of various PAHs, vehicular emissions 0-70%, diesel based sources 0-81% and other miscellaneous sources 0-20% of different PAHs. The contributions of major pyrolytic and petrogenic sources to the total PAHs were 56 and 42%, respectively. Further, the combustion related sources contribute major fraction of the carcinogenic PAHs in the study area. High correlation coefficient (R2 > 0.75 for most PAHs) between the measured and predicted concentrations of PAHs suggests for the applicability of the PCA/APCS receptor modeling approach for estimation of source contribution to the PAHs in particulates.

The Investigation of the Impact of SO2 Emissions from the Hong Kong International Airport

NASA Astrophysics Data System (ADS)

Gray, J. P.; Lau, A. K.; Yuan, Z.

2009-12-01

A previous study of the emissions from Hong Kong’s International Airport (HKIA) utilized a semi-quantitative wind direction and speed technique and identified HKIA as a significant source of SO2 in the region. This study however was based on a single data point and the conclusions reached appeared to be inconsistent with accepted thinking regarding aircraft and airport emissions, prompting an in-depth look at airport emissions and their impact on neighbouring region. Varied modelling techniques, making use of a more complete dataset, were employed to ensure a more comprehensive and defensible result. A similar analysis technique and the same monitoring station used in the previous study (Tung Chung) were combined with three additional stations to provided coverage to reach more certain conclusions. While results at Tung Chung were similar to those in the previous study, information from the other three sensors pointed to a source further to the north in the direction of the Black Point Coal Power Station and other power plants further to the north in Mainland China. This conclusion was confirmed by use of the CALMET / CALPUFF model to reproduce emission plumes from major sources within the region on problem days. The modelled results clearly showed that, in the cases simulated, pollution events noted at Tung Chung were primarily influenced by emissions originating at Hong Kong’s and Mainland China’s power stations, and the impact from HKIA is small. This study reiterates the importance of proper identification of all major sources in wind receptor type studies.

An AzTEC 1.1mm survey of the GOODS-N field - II. Multiwavelength identifications and redshift distribution

NASA Astrophysics Data System (ADS)

Chapin, Edward L.; Pope, Alexandra; Scott, Douglas; Aretxaga, Itziar; Austermann, Jason E.; Chary, Ranga-Ram; Coppin, Kristen; Halpern, Mark; Hughes, David H.; Lowenthal, James D.; Morrison, Glenn E.; Perera, Thushara A.; Scott, Kimberly S.; Wilson, Grant W.; Yun, Min S.

2009-10-01

We present results from a multiwavelength study of 29 sources (false detection probabilities <5 per cent) from a survey of the Great Observatories Origins Deep Survey-North (GOODS-N) field at 1.1mm using the Astronomical Thermal Emission Camera (AzTEC). Comparing with existing 850μm Submillimetre Common-User Bolometer Array (SCUBA) studies in the field, we examine differences in the source populations selected at the two wavelengths. The AzTEC observations uniformly cover the entire survey field to a 1σ depth of ~1mJy. Searching deep 1.4GHz Very Large Array (VLA) and Spitzer 3-24μm catalogues, we identify robust counterparts for 21 1.1mm sources, and tentative associations for the remaining objects. The redshift distribution of AzTEC sources is inferred from available spectroscopic and photometric redshifts. We find a median redshift of z = 2.7, somewhat higher than z = 2.0 for 850μm selected sources in the same field, and our lowest redshift identification lies at a spectroscopic redshift z = 1.1460. We measure the 850μm to 1.1mm colour of our sources and do not find evidence for `850μm dropouts', which can be explained by the low signal-to-noise ratio of the observations. We also combine these observed colours with spectroscopic redshifts to derive the range of dust temperatures T, and dust emissivity indices β for the sample, concluding that existing estimates T ~ 30K and β ~ 1.75 are consistent with these new data.

Future research needs associated with the assessment of potential human health risks from exposure to toxic ambient air pollutants.

PubMed Central

Möller, L; Schuetzle, D; Autrup, H

1994-01-01

This paper presents key conclusions and future research needs from a Workshop on the Risk Assessment of Urban Air, Emissions, Exposure, Risk Identification, and Quantification, which was held in Stockholm during June 1992 by 41 participants from 13 countries. Research is recommended in the areas of identification and quantification of toxics in source emissions and ambient air, atmospheric transport and chemistry, exposure level assessment, the development of improved in vitro bioassays, biomarker development, the development of more accurate epidemiological methodologies, and risk quantification techniques. Studies are described that will be necessary to assess and reduce the level of uncertainties associated with each step of the risk assessment process. International collaborative research efforts between industry and government organizations are recommended as the most effective way to carry out this research. PMID:7529703

Standoff Mid-Infrared Emissive Imaging Spectroscopy for Identification and Mapping of Materials in Polychrome Objects.

PubMed

Gabrieli, Francesca; Dooley, Kathryn A; Zeibel, Jason G; Howe, James D; Delaney, John K

2018-06-18

Microscale mid-infrared (mid-IR) imaging spectroscopy is used for the mapping of chemical functional groups. The extension to macroscale imaging requires that either the mid-IR radiation reflected off or that emitted by the object be greater than the radiation from the thermal background. Reflectance spectra can be obtained using an active IR source to increase the amount of radiation reflected off the object, but rapid heating of greater than 4 °C can occur, which is a problem for paintings. Rather than using an active source, by placing a highly reflective tube between the painting and camera and introducing a low temperature source, thermal radiation from the room can be reduced, allowing the IR radiation emitted by the painting to dominate. Thus, emissivity spectra of the object can be recovered. Using this technique, mid-IR emissivity image cubes of paintings were collected at high collection rates with a low-noise, line-scanning imaging spectrometer, which allowed pigments and paint binders to be identified and mapped. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Aspect-dependent radiated noise analysis of an underway autonomous underwater vehicle.

PubMed

Gebbie, John; Siderius, Martin; Allen, John S

2012-11-01

This paper presents an analysis of the acoustic emissions emitted by an underway REMUS-100 autonomous underwater vehicle (AUV) that were obtained near Honolulu Harbor, HI using a fixed, bottom-mounted horizontal line array (HLA). Spectral analysis, beamforming, and cross-correlation facilitate identification of independent sources of noise originating from the AUV. Fusion of navigational records from the AUV with acoustic data from the HLA allows for an aspect-dependent presentation of calculated source levels of the strongest propulsion tone.

Infrasonic emissions from local meteorological events: A summary of data taken throughout 1984

NASA Technical Reports Server (NTRS)

Zuckerwar, A. J.

1986-01-01

Records of infrasonic signals, propagating through the Earth's atmosphere in the frequency band 2 to 16 Hz, were gathered on a three microphone array at Langley Research Center throughout the year 1984. Digital processing of these records fulfilled three functions: time delay estimation, based on an adaptive filter; source location, determined from the time delay estimates; and source identification, based on spectral analysis. Meteorological support was provided by significant meteorological advisories, lightning locator plots, and daily reports from the Air Weather Service. The infrasonic data are organized into four characteristic signatures, one of which is believed to contain emissions from local meteorological sources. This class of signature prevailed only on those days when major global meteorological events appeared in or near to eastern United States. Eleven case histories are examined. Practical application of the infrasonic array in a low level wing shear alert system is discussed.

The nature of ULX source M101 X-1: optically thick outflow from a stellar mass black hole

NASA Astrophysics Data System (ADS)

Shen, Rong-Feng; Barniol Duran, Rodolfo; Nakar, Ehud; Piran, Tsvi

2015-02-01

The nature of ultraluminous X-ray sources (ULXs) has long been plagued by an ambiguity about whether the central compact objects are intermediate-mass (IMBH, ≳103 M⊙) or stellar-mass (a few tens M⊙) black holes (BHs). The high-luminosity (≃1039 erg s-1) and supersoft spectrum (T ≃ 0.1 keV) during the high state of the ULX source X-1 in the galaxy M101 suggest a large emission radius (≳109 cm), consistent with being an IMBH accreting at a sub-Eddington rate. However, recent kinematic measurement of the binary orbit of this source and identification of the secondary as a Wolf-Rayet star suggest a stellar-mass BH primary with a super-Eddington accretion. If that is the case, a hot, optically thick outflow from the BH can account for the large emission radius and the soft spectrum. By considering the interplay of photons' absorption and scattering opacities, we determine the radius and mass density of the emission region of the outflow and constrain the outflow mass-loss rate. The analysis presented here can be potentially applied to other ULXs with thermally dominated spectra, and to other super-Eddington accreting sources.

IDENTIFICATION OF FMC EMISSION SOURCES CONTRIBUTING TO AMBIENT PM10 ON THE FORT HALL RESERVATION

EPA Science Inventory

More than 300 air change rate experiments were completed in two occupied residences: a two-story detached house in Redwood City, CA, and a three-story townhouse in Reston, VA. A continuous monitor was used to measure the decay of SF6 tracer gas over periods of 1-18 hr. Each e...

Effects of downscaled high-resolution meteorological data on the PSCF identification of emission sources

DOE PAGES

Cheng, Meng -Dawn; Kabela, Erik D.

2016-04-30

The Potential Source Contribution Function (PSCF) model has been successfully used for identifying regions of emission source at a long distance in this study, the PSCF model relies on backward trajectories calculated by the Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model. In this study, we investigated the impacts of grid resolution and Planetary Boundary Layer (PBL) parameterization (e.g., turbulent transport of pollutants) on the PSCF analysis. The Mellor-Yamada-Janjic (MYJ) and Yonsei University (YUS) parameterization schemes were selected to model the turbulent transport in the PBL within the Weather Research and Forecasting (WRF version 3.6) model. Two separate domain grid sizesmore » (83 and 27 km) were chosen in the WRF downscaling in generating the wind data for driving the HYSPLIT calculation. The effects of grid size and PBL parameterization are important in incorporating the influ- ence of regional and local meteorological processes such as jet streaks, blocking patterns, Rossby waves, and terrain-induced convection on the transport of pollutants by a wind trajectory. We found high resolution PSCF did discover and locate source areas more precisely than that with lower resolution meteorological inputs. The lack of anticipated improvement could also be because a PBL scheme chosen to produce the WRF data was only a local parameterization and unable to faithfully duplicate the real atmosphere on a global scale. The MYJ scheme was able to replicate PSCF source identification by those using the Reanalysis and discover additional source areas that was not identified by the Reanalysis data. In conclusion, a potential benefit for using high-resolution wind data in the PSCF modeling is that it could discover new source location in addition to those identified by using the Reanalysis data input.« less

[Estimation inventory of polycyclic aromatic hydrocarbons (PAHs) from anthropogenic sources and its impacts within the Yanghe Watershed, an important water-source site of Beijing, China].

PubMed

Gao, Jia-Jia; Luo, Wei; Xi, Xiao-Xia

2014-12-01

The Yanghe Watershed, situated at the upwind of Beijing, is an important water-source site and ecologic protection barrier for Beijing and Zhangjiakou cities. The Yanghe Watershed is also a farming-pastoral transitional area and an ecologically vulnerable and sensitive region, as well as the place applying for Winter Olympic Game in 2022. Establishment of atmospheric emissions inventory of polycyclic aromatic hydrocarbons (PAHs) and identification of its sources within the Yanghe Watershed and its possible transportation paths to Beijing can help us get a better understanding of regional environmental pollution (especially air environmental pollution) in Beijing-Zhangjiakou area. In the present study, PAHs emission from different counties and cities within the Yanghe Watershed in 2012 was calculated based on the statistical data of local industries, agriculture and resident living while PAHs emission factors were estimated. According to the cluster analysis for air transport trajectories, main categories of air masses were obtained. Results indicated that total emission of PAHs in 2012 was 4.4 x 10(2) t. Coal combustion and crop-straw burning were the most important emission sources of PAHs, accounting for 76% and 16% of total emission of PAHs, respectively. Xuanhua county had the greatest emission of PAHs (49 t), followed by Xinghe (36 t), Tianzhen (32 t), Huailai (24 t) and Wanquan (15 t). In emission of 16 isomers of PAHs, the emission of high molecular weight isomers containing 4-6 rings was approximate to that of low molecular weight isomers containing 2-3 rings, accounting for approximately 50% of total emission of PAHs. Emission of PAHs had positive correlations with gross industrial production (GIP) (r = 0.96, P < 0.05) and resident income (RI) (r = 0.94, P < 0.05) and population density (PD) (r = 0.92, P < 0.05), but negatively correlated with land area (LA) (r = - 0.9, P < 0.05) and no significant correlationship with gross output value of agriculture (GOA) (r = 0.026, P > 0.01). The high emission of PAHs within the Yanghe Watershed was associated with local energy structure and residents' consumption level. Combined the back trajectory analysis with PAHs emission, high amount of PAHs could be transported to Beijing by northwest airflow, suggesting its potential ecological risk and human health effect in Beijing.

Identification of the sources of primary organic aerosols at urban schools: a molecular marker approach.

PubMed

Crilley, Leigh R; Qadir, Raeed M; Ayoko, Godwin A; Schnelle-Kreis, Jürgen; Abbaszade, Gülcin; Orasche, Jürgen; Zimmermann, Ralf; Morawska, Lidia

2014-08-01

Children are particularly susceptible to air pollution and schools are examples of urban microenvironments that can account for a large portion of children's exposure to airborne particles. Thus this paper aimed to determine the sources of primary airborne particles that children are exposed to at school by analyzing selected organic molecular markers at 11 urban schools in Brisbane, Australia. Positive matrix factorization analysis identified four sources at the schools: vehicle emissions, biomass burning, meat cooking and plant wax emissions accounting for 45%, 29%, 16% and 7%, of the organic carbon respectively. Biomass burning peaked in winter due to prescribed burning of bushland around Brisbane. Overall, the results indicated that both local (traffic) and regional (biomass burning) sources of primary organic aerosols influence the levels of ambient particles that children are exposed at the schools. These results have implications for potential control strategies for mitigating exposure at schools. Copyright © 2014 Elsevier Ltd. All rights reserved.

Mobile Methane Monitoring Surveys of the Pinedale Anticline Development in the Upper Green River Basin of Wyoming

NASA Astrophysics Data System (ADS)

Field, R. A.; Soltis, J.; Murphy, S. M.; Montague, D. C.

2013-12-01

Methane emissions from the oil and gas sector have become part of a wider debate of the magnitude of climate change impacts from different fossil fuels. This debate is contentious, as a wide range of estimates of development area leakage rates have been postulated. Here we present the results of mobile monitoring performed in the Pinedale Anticline, WY (PAPA) development. A 4-hour circuit upwind, downwind and within the development was designed to determine methane distributions relative to background concentrations. The circuit was repeated thirty-two times to assess the influence of meteorology and emission sources upon measured values. Figure 1 is a composite of methane data for the project. This pilot project enabled identification of areas and emission sources for subsequent plume quantification studies planned for 2014. Here we present the finding of the circuits through mapping and site comparisons. Along with the methane measurements, mobile ozone and oxides of nitrogen observations were also performed, thereby facilitating a better understanding of the phenomenon of wintertime ground level ozone. Building upon surveys from 2012, we also carried out canister measurements of VOC at selected sites to demonstrate the importance of relating methane and selected VOC concentrations when identifying variations in the contributions of emission sources to ambient measurements. While methane and C2 to C5 alkanes elevations are widespread and highly correlated, those of higher molecular weight VOC, in particular benzene, toluene and xylene isomers, show the importance of emission sources other than wet gas leakage. We discuss the utility of 3D visualization of methane data for illustrating the distribution of leakage relative to emission sources. The influence of emission sources and meteorology upon the data is explored through a comparative analysis of the circuit data. This assessment sets the foundation for planned plume quantification. Finally we compare the mobile data with 1-minute data from the Wyoming DEQ site at Boulder, WY, to determine how well the site represents conditions in the surrounding area. Effective policy decisions require better coupling of air quality measurements and emission inventories. We outline an approach that links regulatory network site data with mobile monitoring and plume quantification that should reduce uncertainty for determining the magnitude of methane emissions from oil and gas sources. Pinedale Anticline methane concentrations for mobile monitoring circuits 2/12/2013 to 3/8/2013

Identification, Attribution, and Quantification of Highly Heterogeneous Methane Sources Using a Mobile Stable Isotope Analyzer

NASA Astrophysics Data System (ADS)

Crosson, E.; Rella, C.; Cunningham, K.

2012-04-01

Despite methane's importance as a potent greenhouse gas second only to carbon dioxide in the magnitude of its contribution to global warming, natural contributions to the overall methane budget are only poorly understood. A big contributor to this gap in knowledge is the highly spatially and temporally heterogeneous nature of most natural (and for that matter anthropogenic) methane sources. This high degree of heterogeneity, where the methane emission rates can vary over many orders of magnitude on a spatial scale of meters or even centimeters, and over a temporal scale of minutes or even seconds, means that traditional methods of emissions flux estimation, such as flux chambers or eddy-covariance, are difficult or impossible to apply. In this paper we present new measurement methods that are capable of detecting, attributing, and quantifying emissions from highly heterogeneous sources. These methods take full advantage of the new class of methane concentration and stable isotope analyzers that are capable of laboratory-quality analysis from a mobile field platform in real time. In this paper we present field measurements demonstrating the real-time detection of methane 'hot spots,' attribution of the methane to a source process via real-time stable isotope analysis, and quantification of the emissions flux using mobile concentration measurements of the horizontal and vertical atmospheric dispersion, combined with atmospheric transport calculations. Although these techniques are applicable to both anthropogenic and natural methane sources, in this initial work we focus primarily on landfills and fugitive emissions from natural gas distribution, as these sources are better characterized, and because they provide a more reliable and stable source of methane for quantifying the measurement uncertainty inherent in the different methods. Implications of these new technologies and techniques are explored for the quantification of natural methane sources in a variety of environments, including wetlands, peatlands, and the arctic.

Sources of nitrogen and phosphorus emissions to Irish rivers: estimates from the Source Load Apportionment Model (SLAM)

NASA Astrophysics Data System (ADS)

Mockler, Eva; Deakin, Jenny; Archbold, Marie; Daly, Donal; Bruen, Michael

2017-04-01

More than half of the river and lake water bodies in Europe are at less than good ecological status or potential, and diffuse pollution from agriculture remains a major, but not the only, cause of this poor performance. In Ireland, it is evident that agri-environmental policy and land management practices have, in many areas, reduced nutrient emissions to water, mitigating the potential impact on water quality. However, additional measures may be required in order to further decouple the relationship between agricultural productivity and emissions to water, which is of vital importance given the on-going agricultural intensification in Ireland. Catchment management can be greatly supported by modelling, which can reduce the resources required to analyse large amounts of information and can enable investigations and measures to be targeted. The Source Load Apportionment Model (SLAM) framework was developed to support catchment management in Ireland by characterising the contributions from various sources of phosphorus (P) and nitrogen (N) emissions to water. The SLAM integrates multiple national spatial datasets relating to nutrient emissions to surface water, including land use and physical characteristics of the sub-catchments to predict emissions from point (wastewater, industry discharges and septic tank systems) and diffuse sources (agriculture, forestry, peatlands, etc.). The annual nutrient emissions predicted by the SLAM were assessed against nutrient monitoring data for 16 major river catchments covering 50% of the area of Ireland. At national scale, results indicate that the total average annual emissions to surface water in Ireland are over 2,700 t yr-1 of P and 80,000 t yr-1 of N. The SLAM results include the proportional contributions from individual sources at a range of scales from sub-catchment to national, and show that the main sources of P are from wastewater and agriculture, with wide variations across the country related to local anthropogenic pressures and the hydrogeological setting. Agriculture is the main source of N emissions to water across all regions of Ireland. The SLAM results have been incorporated into an Integrated Catchment Management process and used in conjunction with monitoring data and local knowledge during the characterisation of all Irish water bodies by the Environmental Protection Agency. This demonstrates the successful integration of research into catchment management to inform the identification of (i) the sources of nutrients at regional and local scales and (ii) the potential significant pressures and appropriate mitigation measures.

Nature of the Diffuse Source and Its Central Point-like Source in SNR 0509–67.5

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

Litke, Katrina C.; Chu, You-Hua; Holmes, Abigail

We examine a diffuse emission region near the center of SNR 0509−67.5 to determine its nature. Within this diffuse region we observe a point-like source that is bright in the near-IR, but is not visible in the B and V bands. We consider an emission line observed at 6766 Å and the possibilities that it is Ly α , H α , and [O ii] λ 3727. We examine the spectral energy distribution (SED) of the source, comprised of Hubble Space Telescope B , V , I , J , and H bands in addition to Spitzer /IRAC 3.6, 4.5,more » 5.8, and 8 μ m bands. The peak of the SED is consistent with a background galaxy at z ≈ 0.8 ± 0.2 and a possible Balmer jump places the galaxy at z ≈ 0.9 ± 0.3. These SED considerations support the emission line’s identification as [O ii] λ 3727. We conclude that the diffuse source in SNR 0509−67.5 is a background galaxy at z ≈ 0.82. Furthermore, we identify the point-like source superposed near the center of the galaxy as its central bulge. Finally, we find no evidence for a surviving companion star, indicating a double-degenerate origin for SNR 0509−67.5.« less

Accretion states in X-ray binaries and their connection to GeV emission

NASA Astrophysics Data System (ADS)

Koerding, Elmar

Accretion onto compact objects is intrinsically a multi-wavelength phenomenon: it shows emis-sion components visible from the radio to GeV bands. In X-ray binaries one can well observe the evolution of a single source under changes of the accretion rate and thus study the interplay between the different emission components.I will introduce the phenomenology of X-ray bina-ries and their accretion states and present our current understanding of the interplay between the optically thin and optically thick part of the accretion flow and the jet.The recent detection of the Fermi Large Area Telescope of a variable high-energy source coinciding with the position of the x-ray binary Cygnus X-3 will be presented. Its identification with Cygnus X-3 has been secured by the detection of its orbital period in gamma rays, as well as the correlation of the LAT flux with radio emission from the relativistic jets of Cygnus X-3. This will be interpreted in the context of the accretion states of the X-ray binary.

Polarization and long-term variability of Sgr A* X-ray echo

NASA Astrophysics Data System (ADS)

Churazov, E.; Khabibullin, I.; Ponti, G.; Sunyaev, R.

2017-06-01

We use a model of the molecular gas distribution within ˜100 pc from the centre of the Milky Way (Kruijssen, Dale & Longmore) to simulate time evolution and polarization properties of the reflected X-ray emission, associated with the past outbursts from Sgr A*. While this model is too simple to describe the complexity of the true gas distribution, it illustrates the importance and power of long-term observations of the reflected emission. We show that the variable part of X-ray emission observed by Chandra and XMM-Newton from prominent molecular clouds is well described by a pure reflection model, providing strong support of the reflection scenario. While the identification of Sgr A* as a primary source for this reflected emission is already a very appealing hypothesis, a decisive test of this model can be provided by future X-ray polarimetric observations, which will allow placing constraints on the location of the primary source. In addition, X-ray polarimeters (like, e.g. XIPE) have sufficient sensitivity to constrain the line-of-sight positions of molecular complexes, removing major uncertainty in the model.

Carbon footprint as an environmental sustainability indicator for the particleboard produced in Pakistan.

PubMed

Hussain, Majid; Naseem Malik, Riffat; Taylor, Adam

2017-05-01

This study quantified the carbon footprint of particleboard production in Pakistan using a cradle-to-gate life cycle assessment approach. The system boundary comprised raw materials acquisition, transport, particleboard manufacture and finished product distribution. Primary data were collected through surveys and meetings with particleboard manufacturers. Secondary data were taken from the literature. Greenhouse gas emissions from off-site industrial operations of the particleboard industry represented 52% of the total emissions from the production of 1.0m 3 of particleboard in Pakistan. The on-site industrial operations cause direct greenhouse gas emissions and accounted for 48% of the total emissions. These operations included energy consumption in stationary sources, the company-owned vehicle fleet, and the distribution and marketing of the finished product. The use of natural gas combustion in the stationary and mobile sources, raw material transport and urea-formaldehyde resin production chain accounted for the highest emissions from the particleboard production chain in Pakistan. The identification of the major hotspots in the particleboard production chain can assist the wood panel industry to improve their environmental profile. More efforts are needed to investigate the urea-formaldehyde resin production chain and substitution of roundwood with wood and agri-residues to assess the potential improvements. In addition, renewable energy sources should be encouraged to avoid greenhouse gas emissions by substituting fossil energy. This study also provides a benchmark for future research work to formulate comprehensive greenhouse gas emissions reduction plans, because no previous research work is available on the carbon footprint of particleboard production in Pakistan. Copyright © 2017 Elsevier Inc. All rights reserved.

Identification of phosphorus emission hotspots in agricultural catchments

PubMed Central

Kovacs, Adam; Honti, Mark; Zessner, Matthias; Eder, Alexander; Clement, Adrienne; Blöschl, Günter

2012-01-01

An enhanced transport-based management approach is presented, which is able to support cost-effective water quality management with respect to diffuse phosphorus pollution. Suspended solids and particulate phosphorus emissions and their transport were modeled in two hilly agricultural watersheds (Wulka River in Austria and Zala River in Hungary) with an improved version of the catchment-scale PhosFate model. Source and transmission areas were ranked by an optimization method in order to provide a priority list of the areas of economically efficient (optimal) management alternatives. The model was calibrated and validated at different gauges and for various years. The spatial distribution of the emissions shows that approximately one third of the catchment area is responsible for the majority of the emissions. However, only a few percent of the source areas can transport fluxes to the catchment outlet. These effective source areas, together with the main transmission areas are potential candidates for improved management practices. In accordance with the critical area concept, it was shown that intervention with better management practices on a properly selected small proportion of the total area (1–3%) is sufficient to reach a remarkable improvement in water quality. If soil nutrient management is also considered in addition to water quality, intervention on 4–12% of the catchment areas can fulfill both aspects. PMID:22771465

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

Gutiérrez, Carlos M.; Moon, Dae-Sik, E-mail: cgc@iac.es

We present the identification and characterization of the optical counterpart to 2XMM J011942.7+032421, one of the most luminous and distant ultra-luminous X-ray sources (ULXs). The counterpart is located near a star-forming region in a spiral arm of the galaxy NGC 470 with u, g, and r magnitudes of 21.53, 21.69, and 21.71 mag, respectively. The luminosity of the counterpart is much larger than that of a single O-type star, indicating that it may be a stellar cluster. Our optical spectroscopic observations confirm the association of the X-ray source and the optical counterpart with its host galaxy NGC 470, which validates the high,more » ≳10{sup 41} erg s{sup -1}, X-ray luminosity of the source. Its optical spectrum is embedded with numerous emission lines, including H recombination lines, metallic forbidden lines, and more notably the high-ionization He II (λ4686) line. That line shows a large velocity dispersion of ≅410 km s{sup -1}, consistent with the existence of a compact (<5 AU) highly ionized accretion disk rotating around the central X-ray source. The ∼1.4 × 10{sup 37} erg s{sup -1} luminosity of the He II line emission makes the source one of the most luminous ULXs in that emission. This, together with the high X-ray luminosity and the large velocity dispersion of the He II emission, suggests that the source is an ideal candidate for more extensive follow-up observations for understanding the nature of hyper-luminous X-ray sources, a more luminous subgroup of ULXs, and more likely candidates for intermediate-mass black holes.« less

Resonant-type MEMS transducers excited by two acoustic emission simulation techniques

NASA Astrophysics Data System (ADS)

Ozevin, Didem; Greve, David W.; Oppenheim, Irving J.; Pessiki, Stephen

2004-07-01

Acoustic emission testing is a passive nondestructive testing technique used to identify the onset and characteristics of damage through the detection and analysis of transient stress waves. Successful detection and implementation of acoustic emission requires good coupling, high transducer sensitivity and ability to discriminate noise from real signals. We report here detection of simulated acoustic emission signals using a MEMS chip fabricated in the multi-user polysilicon surface micromachining (MUMPs) process. The chip includes 18 different transducers with 10 different resonant frequencies in the range of 100 kHz to 1 MHz. It was excited by two different source simulation techniques; pencil lead break and impact loading. The former simulation was accomplished by breaking 0.5 mm lead on the ceramic package. Four transducer outputs were collected simultaneously using a multi-channel oscilloscope. The impact loading was repeated for five different diameter ball bearings. Traditional acoustic emission waveform analysis methods were applied to both data sets to illustrate the identification of different source mechanisms. In addition, a sliding window Fourier transform was performed to differentiate frequencies in time-frequency-amplitude domain. The arrival and energy contents of each resonant frequency were investigated in time-magnitude plots. The advantages of the simultaneous excitation of resonant transducers on one chip are discussed and compared with broadband acoustic emission transducers.

Demonstration of an ethane spectrometer for methane source identification.

PubMed

Yacovitch, Tara I; Herndon, Scott C; Roscioli, Joseph R; Floerchinger, Cody; McGovern, Ryan M; Agnese, Michael; Pétron, Gabrielle; Kofler, Jonathan; Sweeney, Colm; Karion, Anna; Conley, Stephen A; Kort, Eric A; Nähle, Lars; Fischer, Marc; Hildebrandt, Lars; Koeth, Johannes; McManus, J Barry; Nelson, David D; Zahniser, Mark S; Kolb, Charles E

2014-07-15

Methane is an important greenhouse gas and tropospheric ozone precursor. Simultaneous observation of ethane with methane can help identify specific methane source types. Aerodyne Ethane-Mini spectrometers, employing recently available mid-infrared distributed feedback tunable diode lasers (DFB-TDL), provide 1 s ethane measurements with sub-ppb precision. In this work, an Ethane-Mini spectrometer has been integrated into two mobile sampling platforms, a ground vehicle and a small airplane, and used to measure ethane/methane enhancement ratios downwind of methane sources. Methane emissions with precisely known sources are shown to have ethane/methane enhancement ratios that differ greatly depending on the source type. Large differences between biogenic and thermogenic sources are observed. Variation within thermogenic sources are detected and tabulated. Methane emitters are classified by their expected ethane content. Categories include the following: biogenic (<0.2%), dry gas (1-6%), wet gas (>6%), pipeline grade natural gas (<15%), and processed natural gas liquids (>30%). Regional scale observations in the Dallas/Fort Worth area of Texas show two distinct ethane/methane enhancement ratios bridged by a transitional region. These results demonstrate the usefulness of continuous and fast ethane measurements in experimental studies of methane emissions, particularly in the oil and natural gas sector.

Chemical compositions and source identification of PM₂.₅ aerosols for estimation of a diesel source surrogate.

PubMed

Sahu, Manoranjan; Hu, Shaohua; Ryan, Patrick H; Le Masters, Grace; Grinshpun, Sergey A; Chow, Judith C; Biswas, Pratim

2011-06-01

Exposure to traffic-related pollution during childhood has been associated with asthma exacerbation, and asthma incidence. The objective of the Cincinnati Childhood Allergy and Air Pollution Study (CCAAPS) is to determine if the development of allergic and respiratory disease is associated with exposure to diesel engine exhaust particles. A detailed receptor model analyses was undertaken by applying positive matrix factorization (PMF) and UNMIX receptor models to two PM₂.₅ data sets: one consisting of two carbon fractions and the other of eight temperature-resolved carbon fractions. Based on the source profiles resolved from the analyses, markers of traffic-related air pollution were estimated: the elemental carbon attributed to traffic (ECAT) and elemental carbon attributed to diesel vehicle emission (ECAD). Application of UNMIX to the two data sets generated four source factors: combustion related sulfate, traffic, metal processing and soil/crustal. The PMF application generated six source factors derived from analyzing two carbon fractions and seven factors from temperature-resolved eight carbon fractions. The source factors (with source contribution estimates by mass concentrations in parentheses) are: combustion sulfate (46.8%), vegetative burning (15.8%), secondary sulfate (12.9%), diesel vehicle emission (10.9%), metal processing (7.5%), gasoline vehicle emission (5.6%) and soil/crustal (0.7%). Diesel and gasoline vehicle emission sources were separated using eight temperature-resolved organic and elemental carbon fractions. Application of PMF to both datasets also differentiated the sulfate rich source from the vegetative burning source, which are combined in a single factor by UNMIX modeling. Calculated ECAT and ECAD values at different locations indicated that traffic source impacts depend on factors such as traffic volumes, meteorological parameters, and the mode of vehicle operation apart from the proximity of the sites to highways. The difference in ECAT and ECAD, however, was less than one standard deviation. Thus, a cost benefit consideration should be used when deciding on the benefits of an eight or two carbon approach. Published by Elsevier B.V.

40 CFR 52.2620 - Identification of plan.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Ambient standards for particulate matter 9/13/99, 10/29/99 7/28/04, 69 FR 44965. Section 3 Ambient... standards for particulate matter 9/13/99, 10/29/99 7/28/04, 69 FR 44965. Section 3 Emission standards for... sources 9/13/99, 10/29/99 7/28/04, 69 FR 44965. Chapter 8 Section 2 Sweetwater County particulate matter...

Gamma-Ray Emission from the Broad-Line Radio Galaxy 3C 111

NASA Technical Reports Server (NTRS)

Hartman, Robert C.; Kadler, M.; Tueller, Jack

2008-01-01

The broad-line radio galaxy 3C 111 has been suggested as the counterpart of the y-ray source 3EG J0416+3650. While 3C 111 meets most of the criteria for a high-probability identification, like a bright flat-spectrum radio core and a blazar-like broadband SED, in the Third EGRET Catalog, the large positional offset of about 1.5' put 3C 111 outside the 99% probability region for 3EG J0416+3650, making this association questionable. We present a re-analysis of all available archival data for 3C 111 from the EGRET archives, resulting in detection of variable hard-spectrum high-energy gamma-ray emission above 1000 MeV from a position close to the nominal position of 3C 111, in three separate viewing periods (VPs), at a 3sigma level in each. A second variable hard-spectrum source is present nearby. At >100 MeV, one variable soft-spectrum source seems to account for most of the EGRET-detected emission of 3EG J0416+3650. A follow-up Swift UVOT/XRT observation reveals one moderately bright X-ray source in the error box of 3EG J0416+3650, but because of the large EGRET position uncertainty, it is not certain that the X-ray and gamma-ray sources are associated. Another Swift observation near the second (unidentified) hard gamma-ray source detected no X-ray source nearby.

European sources of halocarbons and nitrous oxide - Update 1986

NASA Technical Reports Server (NTRS)

Prather, Michael

1988-01-01

New information on seasonal and secular trends in the releases of CFCl3, CF2Cl2, CCl4, CH3CCl3, and N20 from Europe was obtained as part of the Atmospheric Lifetime Experiment. Semicontinuous measurements of these pollutants were made at Adrigole, Ireland, using lean air from the Atlantic Ocean as a baseline. The results obtained include unambiguous evidence for elevated levels of N2O occurring concurrent with halocarbon pollution events; the detection of trends in the relative emission of different halocarbons; the discovery of seasonal variations in emission of CF2Cl2, CCl4, and CH3Cl3; the characterization of typical summer and winter pollution episodes; and the identification of weather patterns over Europe that are associated with high concentrations of chlorofluorocarbons at Adrigole. It was estimated that the European source of N2O represents 25 percent of the global emissions associated with combustion and 10 percent of the integrated stratospheric losses.

Direct spectroscopic evidence for ionized polycyclic aromatic hydrocarbons in the interstellar medium.

PubMed

Sloan, G C; Hayward, T L; Allamandola, L J; Bregman, J D; DeVito, B; Hudgins, D M

1999-03-01

Long-slit 8-13 micrometers spectroscopy of the nebula around NGC 1333 SVS 3 reveals spatial variations in the strength and shape of emission features that are probably produced by polycyclic aromatic hydrocarbons (PAHs). Close to SVS 3, the 11.2 micrometers feature develops an excess at approximately 10.8-11.0 micrometers and a feature appears at approximately 10 micrometers. These features disappear with increasing distance from the central source, and they show striking similarities to recent laboratory data of PAH cations, providing the first identification of emission features arising specifically from ionized PAHs in the interstellar medium.

Sources of methane and nitrous oxide in California's Central Valley estimated through direct airborne flux and positive matrix factorization source apportionment of groundbased and regional tall tower measurements

NASA Astrophysics Data System (ADS)

Guha, Abhinav

Methane (CH4) and nitrous oxide (N2O) are two major greenhouse gases that contribute significantly to the increase in anthropogenic radiative-forcing causing perturbations to the earth's climate system. In a watershed moment in the state's history of environmental leadership and commitment, California, in 2006, opted for sharp reductions in their greenhouse gas (GHG) emissions and adopted a long-term approach to address climate change that includes regulation of emissions from individual emitters and source categories. There are large CH4 and N2O emissions sources in the state, predominantly in the agricultural and waste management sector. While these two gases account for < 10% of total annual greenhouse gas emissions of the state, large uncertainties exist in their `bottom-up' accounting in the state GHG inventory. Additionally, an increasing number of `top-down' studies based on ambient observations point towards underestimation of their emissions in the inventory. Three intensive field observation campaigns that were spatially and temporally diverse took place between 2010 and 2013 in the Central Valley of California where the largest known sources of CH4 and N2O (e.g. agricultural systems and dairies) and potentially significant CH4 sources (e.g. oil and gas extraction) are located. The CalNex (California Nexus - Research at the Nexus of Air Quality and Climate Change) field campaign during summer 2010 (May 15 - June 30) took place in the urban core of Bakersfield in the southern San Joaquin Valley, a city whose economy is built around agriculture and the oil and gas industry. During summer of 2011, airborne measurements were performed over a large spatial domain, all across and around the Central Valley as part of the CABERNET (California Airborne BVOC Emission Research in Natural Ecosystem Transects) study. Next, a one-year continuous field campaign (WGC 2012-13, June 2012 - August 2013) was conducted at the Walnut Grove tall tower near the Sacramento-San Joaquin River Delta in the Central Valley. Through analysis of these field measurements, this dissertation presents the apportionment of observed CH4 and N2O concentration enhancements into major source categories along with direct emissions estimates from airborne observations. We perform high-precision measurements of greenhouse gases using gas analyzers based on absorption spectroscopy, and other source marker volatile organic compounds (VOCs) using state of the art VOC measurement systems (e.g. proton transfer reaction mass spectrometry). We combine these measurements with a statistical source apportionment technique called positive matrix factorization (PMF) to evaluate and investigate the major local sources of CH4 and N2O during CalNex and Walnut Grove campaigns. In the CABERNET study, we combine measurements with an airborne approach to a well-established micrometeorological technique (eddy-covariance method) to derive CH4 fluxes over different source regions in the Central Valley. In the CalNex experiments, we demonstrate that dairy and livestock remains the largest source sector of non-CO2 greenhouse gases in the San Joaquin Valley contributing most of the CH4 and much of the measured N2O at Bakersfield. Agriculture is observed to provide another major source of N2O, while vehicle emissions are found to be an insignificant source of N2O, contrary to the current statewide greenhouse gas inventory which includes vehicles as a major source. Our PMF source apportionment also produces an evaporative/fugitive factor but its relative lack of CH4 contributions points to removal processes from vented emissions in the surrounding O&G industry and the overwhelming dominance of the dairy CH4 source. In the CABERNET experiments, we report enhancements of CH4 from a number of sources spread across the spatial domain of the Central Valley that improves our understanding of their distribution and relative strengths. We observe large enhancements of CH4 mixing ratios over the dairy and feedlot intensive regions of Central Valley corresponding with significant flux estimates that are larger than CH4 emission rates reported in the greenhouse gas inventory. We find evidence of significant CH 4 emissions from fugitive and/or vented sources and cogeneration plants in the oil and gas fields of Kern County, all of which are minor to insignificant CH4 sources in the current greenhouse gas inventory. The CABERNET campaign represents the first successful implementation of airborne eddy covariance technique for CH4 flux measurements. At Walnut Grove, we demonstrate the seasonal and temporal dependence of CH4 and N2O sources in the Central Valley. Applying PMF analysis on seasonal GHG-VOC data sets, we again identify dairies and livestock as the dominant source of CH4. A clear temporal dependence of emissions originating from a wetlands / Delta CH4 source is observed while CH4 contributions are also observed from a source originating from upwind urban and natural gas extraction activities. The agricultural soil management source of N2O has a seasonal dependence coincident with the agricultural growing season (and hence, fertilizer use) accounting for a majority of the N2O enhancements during spring and summers but being reduced to a negligible source during late fall and winters when manure management N2O emissions from dairy and livestock dominate the relative distribution. N2O is absent from the 'urban' source, in contrast to the significant contribution to the statewide N2O inventory from vehicle emissions. The application of greenhouse gas source apportionment using VOC tracers as identification tools at two independent sites in the Central Valley over vastly different temporal resolutions provide significant insights into the regional distribution of major CH4 sources. Direct airborne eddy covariance measurements provide a unique opportunity to constrain CH 4 emissions in the Central Valley over regional spatial scales that are not directly observable by ground-based methods. Airborne observations provide identification of 'hotspots' and under-inventoried CH4 sources, while airborne eddy covariance enables quantification of emissions from those area sources that are largely composed of arbitrarily located minor point sources (e.g. dairies and oil fields). The top-down analysis provides confirmation of the dominance of dairy and livestock source for methane emissions in California. Minor but significant contributions to methane emissions are observed from oil and gas extraction, rice cultivation and wetlands; the estimates for these sectors being either negligible (e.g. wetlands) or highly uncertain (e.g. oil and gas extraction) in the statewide inventories and probably underestimated as a proportion of the total inventory. The top-down analysis also confirms agricultural soil management and dairy and livestock as the two principal sources of N2O consistent with the inventory, but shows that N2O contributions attributed to the transportation sector are overestimated in the statewide inventory. These new top down constraints should be used to correct these errors in the current bottom-up inventory, which is a critical step for future assessments of the efficacy of emission reduction regulations. Particularly, measurement techniques like vehicle dynamometer emission calculations (for transportation sources), source-specific short range ground-based inverse dispersion (for dairy and livestock sources), airborne eddy covariance and airborne mass balance approach based emissions estimation (over oil and gas fields) and ground based eddy-covariance (for wetlands and agriculture sector) can be used effectively to generate direct emissions estimates for methane and nitrous oxide that help update and improve the accuracy of the state inventory.

Modulated high-energy gamma-ray emission from the microquasar Cygnus X-3.

PubMed

Abdo, A A; Ackermann, M; Ajello, M; Axelsson, M; Baldini, L; Ballet, J; Barbiellini, G; Bastieri, D; Baughman, B M; Bechtol, K; Bellazzini, R; Berenji, B; Blandford, R D; Bloom, E D; Bonamente, E; Borgland, A W; Brez, A; Brigida, M; Bruel, P; Burnett, T H; Buson, S; Caliandro, G A; Cameron, R A; Caraveo, P A; Casandjian, J M; Cecchi, C; Celik, O; Chaty, S; Cheung, C C; Chiang, J; Ciprini, S; Claus, R; Cohen-Tanugi, J; Cominsky, L R; Conrad, J; Corbel, S; Corbet, R; Dermer, C D; de Palma, F; Digel, S W; do Couto e Silva, E; Drell, P S; Dubois, R; Dubus, G; Dumora, D; Farnier, C; Favuzzi, C; Fegan, S J; Focke, W B; Fortin, P; Frailis, M; Fusco, P; Gargano, F; Gehrels, N; Germani, S; Giavitto, G; Giebels, B; Giglietto, N; Giordano, F; Glanzman, T; Godfrey, G; Grenier, I A; Grondin, M-H; Grove, J E; Guillemot, L; Guiriec, S; Hanabata, Y; Harding, A K; Hayashida, M; Hays, E; Hill, A B; Hjalmarsdotter, L; Horan, D; Hughes, R E; Jackson, M S; Jóhannesson, G; Johnson, A S; Johnson, T J; Johnson, W N; Kamae, T; Katagiri, H; Kawai, N; Kerr, M; Knödlseder, J; Kocian, M L; Koerding, E; Kuss, M; Lande, J; Latronico, L; Lemoine-Goumard, M; Longo, F; Loparco, F; Lott, B; Lovellette, M N; Lubrano, P; Madejski, G M; Makeev, A; Marchand, L; Marelli, M; Max-Moerbeck, W; Mazziotta, M N; McColl, N; McEnery, J E; Meurer, C; Michelson, P F; Migliari, S; Mitthumsiri, W; Mizuno, T; Monte, C; Monzani, M E; Morselli, A; Moskalenko, I V; Murgia, S; Nolan, P L; Norris, J P; Nuss, E; Ohsugi, T; Omodei, N; Ong, R A; Ormes, J F; Paneque, D; Parent, D; Pelassa, V; Pepe, M; Pesce-Rollins, M; Piron, F; Pooley, G; Porter, T A; Pottschmidt, K; Rainò, S; Rando, R; Ray, P S; Razzano, M; Rea, N; Readhead, A; Reimer, A; Reimer, O; Richards, J L; Rochester, L S; Rodriguez, J; Rodriguez, A Y; Romani, R W; Ryde, F; Sadrozinski, H F-W; Sander, A; Saz Parkinson, P M; Sgrò, C; Siskind, E J; Smith, D A; Smith, P D; Spinelli, P; Starck, J-L; Stevenson, M; Strickman, M S; Suson, D J; Takahashi, H; Tanaka, T; Thayer, J B; Thompson, D J; Tibaldo, L; Tomsick, J A; Torres, D F; Tosti, G; Tramacere, A; Uchiyama, Y; Usher, T L; Vasileiou, V; Vilchez, N; Vitale, V; Waite, A P; Wang, P; Wilms, J; Winer, B L; Wood, K S; Ylinen, T; Ziegler, M

2009-12-11

Microquasars are accreting black holes or neutron stars in binary systems with associated relativistic jets. Despite their frequent outburst activity, they have never been unambiguously detected emitting high-energy gamma rays. The Fermi Large Area Telescope (LAT) has detected a variable high-energy source coinciding with the position of the x-ray binary and microquasar Cygnus X-3. Its identification with Cygnus X-3 is secured by the detection of its orbital period in gamma rays, as well as the correlation of the LAT flux with radio emission from the relativistic jets of Cygnus X-3. The gamma-ray emission probably originates from within the binary system, opening new areas in which to study the formation of relativistic jets.

Mercury stable isotope signatures of world coal deposits and historical coal combustion emissions.

PubMed

Sun, Ruoyu; Sonke, Jeroen E; Heimbürger, Lars-Eric; Belkin, Harvey E; Liu, Guijian; Shome, Debasish; Cukrowska, Ewa; Liousse, Catherine; Pokrovsky, Oleg S; Streets, David G

2014-07-01

Mercury (Hg) emissions from coal combustion contribute approximately half of anthropogenic Hg emissions to the atmosphere. With the implementation of the first legally binding UNEP treaty aimed at reducing anthropogenic Hg emissions, the identification and traceability of Hg emissions from different countries/regions are critically important. Here, we present a comprehensive world coal Hg stable isotope database including 108 new coal samples from major coal-producing deposits in South Africa, China, Europe, India, Indonesia, Mongolia, former USSR, and the U.S. A 4.7‰ range in δ(202)Hg (-3.9 to 0.8‰) and a 1‰ range in Δ(199)Hg (-0.6 to 0.4‰) are observed. Fourteen (p < 0.05) to 17 (p < 0.1) of the 28 pairwise comparisons between eight global regions are statistically distinguishable on the basis of δ(202)Hg, Δ(199)Hg or both, highlighting the potential application of Hg isotope signatures to coal Hg emissions tracing. A revised coal combustion Hg isotope fractionation model is presented, and suggests that gaseous elemental coal Hg emissions are enriched in the heavier Hg isotopes relative to oxidized forms of emitted Hg. The model explains to first order the published δ(202)Hg observations on near-field Hg deposition from a power plant and global scale atmospheric gaseous Hg. Yet, model uncertainties appear too large at present to permit straightforward Hg isotope source identification of atmospheric forms of Hg. Finally, global historical (1850-2008) coal Hg isotope emission curves were modeled and indicate modern-day mean δ(202)Hg and Δ(199)Hg values for bulk coal emissions of -1.2 ± 0.5‰ (1SD) and 0.05 ± 0.06‰ (1SD).

VizieR Online Data Catalog: Vatican Emission-line stars (Coyne+ 1974-1983)

NASA Astrophysics Data System (ADS)

Coyne, G. V.; Lee, T. A.; de Graeve, E.; Wisniewski, W.; Corbally, C.; Otten, L. B.; MacConnell, D. J.

2009-10-01

The survey represents a search for Hα emission-line stars, and was conducted with a 12{deg} objective prism on the Vatican Schmidt telescope. The Vatican Emission Stars (VES) survey covers the galactic plane (|b|<=5{deg}) between galactic longitudes 58 and 174{deg}. The catalog was re-examined by B. Skiff (Lowell Observatory), and tne VES stars were cross-identified with modern surveys: GSC (Cat. I/255), Tycho-2 (I/256), 2MASS (II/246), IRAS point source catalog (II/125), MSX6C (V/114), CMC14 (I/304), GSC-2.3 (I/305), UCAC2 (I/289). Cross-identifications are also supplied with HD/BD/GCVS names, and with Dearborn catalog of red stars (II/68). Many of the stars in the first four papers are not early-type emission-line stars, but instead M giants, where the sharp TiO bandhead at 6544{AA} was mistaken for H-{alpha} emission on the objective-prism plates. Based on the revision of paper V and a later list prepared by Jack MacConnell, a column identifies the "non H-alpha" stars explicitly. The links with the Dearborn, IRAS, and MSX catalogues help identify the red stars. These and other identifications and comments are given in the remarks at the end of each line, or in longer notes in a separate file, indicated by an asterisk (*) next to the star number. (3 data files).

VizieR Online Data Catalog: Vatican Emission-line stars (Coyne+ 1974-1983)

NASA Astrophysics Data System (ADS)

Coyne, G. V.; Lee, T. A.; de Graeve, E.; Wisniewski, W.; Corbally, C.; Otten, L. B.; MacConnell, D. J.

2008-03-01

The survey represents a search for Hα emission-line stars, and was conducted with a 12{deg} objective prism on the Vatican Schmidt telescope. The Vatican Emission Stars (VES) survey covers the galactic plane (|b|<=5{deg}) between galactic longitudes 58 and 174{deg}. The catalog was re-examined by B. Skiff (Lowell Observatory), and tne VES stars were cross-identified with modern surveys: GSC (Cat. I/255), Tycho-2 (I/256), 2MASS (II/246), IRAS point source catalog (II/125), MSX6C (V/114), CMC14 (I/304), GSC-2.3 (I/305), UCAC2 (I/289). Cross-identifications are also supplied with HD/BD/GCVS names, and with Dearborn catalog of red stars (II/68). Many of the stars in the first four papers are not early-type emission-line stars, but instead M giants, where the sharp TiO bandhead at 6544{AA} was mistaken for H-{alpha} emission on the objective-prism plates. Based on the revision of paper V and a later list prepared by Jack MacConnell, a column identifies the "non H-alpha" stars explicitly. The links with the Dearborn, IRAS, and MSX catalogues help identify the red stars. These and other identifications and comments are given in the remarks at the end of each line, or in longer notes in a separate file, indicated by an asterisk (*) next to the star number. (2 data files).

N(2)O emissions and source processes in snow-covered soils in the Swiss Alps.

PubMed

Mohn, Joachim; Steinlin, Christine; Merbold, Lutz; Emmenegger, Lukas; Hagedorn, Frank

2013-01-01

Nitrous oxide (N2O) emissions from snow-covered soils represent a significant fraction of the annual flux from alpine, subalpine or cold-temperate regions. In winter 2010-2011, we investigated the temporal variability of N2O emissions and source processes from a subalpine valley in the Swiss Alps. The study included regular measurements of N2O snow profiles at a fixed location and an intensive sampling campaign along a transversal cut through the valley with grassland at the bottom and coniferous forest at the slopes. During the intensive campaign, recently developed laser spectroscopy was employed for high-precision N2O isotopomer analysis. Maximum N2O fluxes (0.77±0.64 nmol m(-2) h(-1)) were found for periods with elevated air temperature and, in contrast to our expectations, were higher from forest than from grassland in mid-February. At maximum snow height (63 cm) the main N2O source processes were heterotrophic denitrification and nitrifier denitrification. The reduction of N2O by heterotrophic denitrifiers was much more pronounced for the grassland compared with the forest soil, as indicated by the (15)N site preferences of 16.4±11.5 ‰ (grassland) and-1.6±2.1 ‰ (forest). This illustrates the potential of laser spectroscopic N2O isotopomer analysis for the identification of source processes even at low emission rates in nutrient poor ecosystems.

Ambient air/near-field measurements of methane and Volatile Organic Compounds (VOCs) from a natural gas facility in Northern Europe

NASA Astrophysics Data System (ADS)

Baudic, Alexia; Gros, Valérie; Bonsang, Bernard; Baisnee, Dominique; Vogel, Félix; Yver Kwok, Camille; Ars, Sébastien; Finlayson, Andrew; Innocenti, Fabrizio; Robinson, Rod

2015-04-01

Since the 1970's, the natural gas consumption saw a rapid growth in large urban centers, thus becoming an important energy resource to meet continuous needs of factories and inhabitants. Nevertheless, it can be a substantial source of methane (CH4) and pollutants in urban areas. For instance, we have determined that about 20% of Volatile Organic Compounds (VOCs) in downtown Paris are originating from this emission source (Baudic, Gros et al., in preparation). Within the framework of the "Fugitive Methane Emissions" (FuME) project (Climate-KIC, EIT); 2-weeks gas measurements were conducted at a gas compressor station in Northern Europe. Continuous ambient air measurements of methane and VOCs concentrations were performed using a cavity ring-down spectrometer (model G2201, Picarro Inc., Santa Clara, USA) and two portable GC-FID (Chromatotec, Saint-Antoine, France), respectively. On-site near-field samplings were also carried out at the source of two pipelines using stainless steel flasks (later analyzed with a laboratory GC-FID). The objective of this study aims to use VOCs as additional tracers in order to better characterize the fugitive methane emissions in a complex environment, which can be affected by several urban sources (road-traffic, others industries, etc.). Moreover, these measurements have allowed determining the chemical composition of this specific source. Our results revealed that the variability of methane and some VOCs was (rather) well correlated, especially for alkanes (ethane, propane, etc.). An analysis of selected events with strong concentrations enhancement was performed using ambient air measurements; thus allowing the preliminary identification of different emission sources. In addition, some flasks were also sampled in Paris to determine the local natural gas composition. A comparison between both was then performed. Preliminary results from these experiments will be presented here.

Time-distance domain transformation for Acoustic Emission source localization in thin metallic plates.

PubMed

Grabowski, Krzysztof; Gawronski, Mateusz; Baran, Ireneusz; Spychalski, Wojciech; Staszewski, Wieslaw J; Uhl, Tadeusz; Kundu, Tribikram; Packo, Pawel

2016-05-01

Acoustic Emission used in Non-Destructive Testing is focused on analysis of elastic waves propagating in mechanical structures. Then any information carried by generated acoustic waves, further recorded by a set of transducers, allow to determine integrity of these structures. It is clear that material properties and geometry strongly impacts the result. In this paper a method for Acoustic Emission source localization in thin plates is presented. The approach is based on the Time-Distance Domain Transform, that is a wavenumber-frequency mapping technique for precise event localization. The major advantage of the technique is dispersion compensation through a phase-shifting of investigated waveforms in order to acquire the most accurate output, allowing for source-sensor distance estimation using a single transducer. The accuracy and robustness of the above process are also investigated. This includes the study of Young's modulus value and numerical parameters influence on damage detection. By merging the Time-Distance Domain Transform with an optimal distance selection technique, an identification-localization algorithm is achieved. The method is investigated analytically, numerically and experimentally. The latter involves both laboratory and large scale industrial tests. Copyright © 2016 Elsevier B.V. All rights reserved.

Mapping methane emissions using the airborne imaging spectrometer AVIRIS-NG

NASA Astrophysics Data System (ADS)

Thorpe, A. K.; Frankenberg, C.; Thompson, D. R.; Duren, R. M.; Bue, B. D.; Green, R. O.

2017-12-01

The next generation Airborne Visible/Infrared Imaging Spectrometer (AVIRIS-NG) has been used to survey large regions and map methane plumes with unambiguous identification of emission source locations. This capability is aided by real time detection and geolocation of gas plumes, permitting adaptive surveys and communication to ground teams for rapid follow up. We present results from AVIRIS-NG flight campaigns in Colorado, New Mexico, and California. Hundreds of plumes were observed, reflecting emissions from the energy sector that include hydraulic fracturing, gas processing plants, tanks, pumpjacks, and pipeline leaks. In some cases, plumes observed by AVIRIS-NG resulted in mitigation. Additional examples will be shown for methane from dairy lagoons, landfills, natural emissions, as well as carbon dioxide from power plants and refineries. We describe the unique capabilities of airborne imaging spectrometers to augment other measurement techniques by efficiently surveying key regions for methane point sources and supporting timely assessment and mitigation. We summarize the outlook for near- and longer-term monitoring capabilities including future satellite systems. Figure caption. AVIRIS-NG true color image subset with superimposed methane plume showing retrieved gas concentrations. Plume extends 200 m downwind of the southern edge of the well pad. Google Earth imagery with finer spatial resolution is also included (red box), indicating that tanks in the inset scene as the source of emissions. Five wells are located at the center of this well pad and all use horizontal drilling to produce mostly natural gas.

Carbon footprint as an environmental sustainability indicator for the particleboard produced in Pakistan

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

Hussain, Majid

This study quantified the carbon footprint of particleboard production in Pakistan using a cradle-to-gate life cycle assessment approach. The system boundary comprised raw materials acquisition, transport, particleboard manufacture and finished product distribution. Primary data were collected through surveys and meetings with particleboard manufacturers. Secondary data were taken from the literature. Greenhouse gas emissions from off-site industrial operations of the particleboard industry represented 52% of the total emissions from the production of 1.0 m{sup 3} of particleboard in Pakistan. The on-site industrial operations cause direct greenhouse gas emissions and accounted for 48% of the total emissions. These operations included energy consumptionmore » in stationary sources, the company-owned vehicle fleet, and the distribution and marketing of the finished product. The use of natural gas combustion in the stationary and mobile sources, raw material transport and urea-formaldehyde resin production chain accounted for the highest emissions from the particleboard production chain in Pakistan. The identification of the major hotspots in the particleboard production chain can assist the wood panel industry to improve their environmental profile. More efforts are needed to investigate the urea-formaldehyde resin production chain and substitution of roundwood with wood and agri-residues to assess the potential improvements. In addition, renewable energy sources should be encouraged to avoid greenhouse gas emissions by substituting fossil energy. This study also provides a benchmark for future research work to formulate comprehensive greenhouse gas emissions reduction plans, because no previous research work is available on the carbon footprint of particleboard production in Pakistan. - Highlights: • We conducted the first carbon footprint assessment of particleboard produced in Pakistan. • System boundary comprised raw materials acquisition, particleboard manufacture and distribution. • Off-site industrial operations were accounted for highest emissions (52%) followed by on-site operations (48%). • Natural gas, materials transport and UF resin use accounted for highest emissions. • Identified potential strategies for GHG emissions reductions from PB production in Pakistan.« less

Ultrabroadband phased-array radio frequency (RF) receivers based on optical techniques

NASA Astrophysics Data System (ADS)

Overmiller, Brock M.; Schuetz, Christopher A.; Schneider, Garrett; Murakowski, Janusz; Prather, Dennis W.

2014-03-01

Military operations require the ability to locate and identify electronic emissions in the battlefield environment. However, recent developments in radio detection and ranging (RADAR) and communications technology are making it harder to effectively identify such emissions. Phased array systems aid in discriminating emitters in the scene by virtue of their relatively high-gain beam steering and nulling capabilities. For the purpose of locating emitters, we present an approach realize a broadband receiver based on optical processing techniques applied to the response of detectors in conformal antenna arrays. This approach utilizes photonic techniques that enable us to capture, route, and process the incoming signals. Optical modulators convert the incoming signals up to and exceeding 110 GHz with appreciable conversion efficiency and route these signals via fiber optics to a central processing location. This central processor consists of a closed loop phase control system which compensates for phase fluctuations induced on the fibers due to thermal or acoustic vibrations as well as an optical heterodyne approach for signal conversion down to baseband. Our optical heterodyne approach uses injection-locked paired optical sources to perform heterodyne downconversion/frequency identification of the detected emission. Preliminary geolocation and frequency identification testing of electronic emissions has been performed demonstrating the capabilities of our RF receiver.

Scientific investigations with the data base HEAO-1 scanning modulator collimator

NASA Technical Reports Server (NTRS)

Schwartz, Daniel A.

1992-01-01

The hardware specification for the Scanning Modulation Collimator (MC) experiment on HEAO-1 was to measure positions of bright (greater than 10(exp -11) ergs/cm(exp 2)s), hard (1 to 15 keV) x-ray sources to 5-10 arcsec, and to measure their size and structure in three energy bands down to 10 arcsec resolution. The scientific purpose of this specification was to enable the identification of these x-ray sources with optical and radio objects in order to elucidate the x-ray emission mechanism and the nature of the candidate astronomical system. The experiment was an outstanding success. Hardware systems functioned perfectly although loss of one (out of eight) proportional counters degraded our sensitivity by about 10 percent. Our aspect solution of 7 arcsec precision, allowed us to achieve statistic-limited location precision for all but the strongest sources. We vigorously pursued a strategy of determining the scientific importance of each identification, and of publishing each scientific result as it came along.

Source identification and apportionment of heavy metals in urban soil profiles.

PubMed

Luo, Xiao-San; Xue, Yan; Wang, Yan-Ling; Cang, Long; Xu, Bo; Ding, Jing

2015-05-01

Because heavy metals (HMs) occurring naturally in soils accumulate continuously due to human activities, identifying and apportioning their sources becomes a challenging task for pollution prevention in urban environments. Besides the enrichment factors (EFs) and principal component analysis (PCA) for source classification, the receptor model (Absolute Principal Component Scores-Multiple Linear Regression, APCS-MLR) and Pb isotopic mixing model were also developed to quantify the source contribution for typical HMs (Cd, Co, Cr, Cu, Mn, Ni, Pb, Zn) in urban park soils of Xiamen, a representative megacity in southeast China. Furthermore, distribution patterns of their concentrations and sources in 13 soil profiles (top 20 cm) were investigated by different depths (0-5, 5-10, 10-20 cm). Currently the principal anthropogenic source for HMs in urban soil of China is atmospheric deposition from coal combustion rather than vehicle exhaust. Specifically for Pb source by isotopic model ((206)Pb/(207)Pb and (208)Pb/(207)Pb), the average contributions were natural (49%)>coal combustion (45%)≫traffic emissions (6%). Although the urban surface soils are usually more contaminated owing to recent and current human sources, leaching effects and historic vehicle emissions can also make deep soil layer contaminated by HMs. Copyright © 2015 Elsevier Ltd. All rights reserved.

Resolved atomic lines reveal outflows in two ultraluminous X-ray sources.

PubMed

Pinto, Ciro; Middleton, Matthew J; Fabian, Andrew C

2016-05-05

Ultraluminous X-ray sources are extragalactic, off-nucleus, point sources in galaxies, and have X-ray luminosities in excess of 3 × 10(39) ergs per second. They are thought to be powered by accretion onto a compact object. Possible explanations include accretion onto neutron stars with strong magnetic fields, onto stellar-mass black holes (of up to 20 solar masses) at or in excess of the classical Eddington limit, or onto intermediate-mass black holes (10(3)-10(5) solar masses). The lack of sufficient energy resolution in previous analyses has prevented an unambiguous identification of any emission or absorption lines in the X-ray band, thereby precluding a detailed analysis of the accretion flow. Here we report the presence of X-ray emission lines arising from highly ionized iron, oxygen and neon with a cumulative significance in excess of five standard deviations, together with blueshifted (about 0.2 times light velocity) absorption lines of similar significance, in the high-resolution X-ray spectra of the ultraluminous X-ray sources NGC 1313 X-1 and NGC 5408 X-1. The blueshifted absorption lines must occur in a fast-outflowing gas, whereas the emission lines originate in slow-moving gas around the source. We conclude that the compact object in each source is surrounded by powerful winds with an outflow velocity of about 0.2 times that of light, as predicted by models of accreting supermassive black holes and hyper-accreting stellar-mass black holes.

Review on recent progress in observations, source identifications and countermeasures of PM2.5.

PubMed

Liang, Chun-Sheng; Duan, Feng-Kui; He, Ke-Bin; Ma, Yong-Liang

2016-01-01

Recently, PM2.5 (atmospheric fine particulate matter with aerodynamic diameter ≤ 2.5 μm) have received so much attention that the observations, source appointment and countermeasures of it have been widely studied due to its harmful impacts on visibility, mood (mental health), physical health, traffic safety, construction, economy and nature, as well as its complex interaction with climate. A review on the PM2.5 related research is necessary. We start with summary of chemical composition and characteristics of PM2.5 that contains both macro and micro observation results and analysis, wherein the temporal variability of concentrations of PM2.5 and major components in many recent reports is embraced. This is closely followed by an overview of source appointment, including the composition and sources of PM2.5 in different countries in the six inhabitable continents based on the best available results. Besides summarizing PM2.5 pollution countermeasures by policy, planning, technology and ideology, the World Air Day is proposed to be established to inspire and promote the crucial social action in energy-saving and emission-reduction. Some updated knowledge of the important topics (such as formation and evolution mechanisms of hazes, secondary aerosols, aerosol mass spectrometer, organic tracers, radiocarbon, emissions, solutions for air pollution problems, etc.) is also included in the present review by logically synthesizing the studies. In addition, the key research challenges and future directions are put forward. Despite our efforts, our understanding of the recent reported observations, source identifications and countermeasures of PM2.5 is limited, and subsequent efforts both of the authors and readers are needed. Copyright © 2015 Elsevier Ltd. All rights reserved.

Identifying risk sources of air contamination by polycyclic aromatic hydrocarbons.

PubMed

Huzlik, Jiri; Bozek, Frantisek; Pawelczyk, Adam; Licbinsky, Roman; Naplavova, Magdalena; Pondelicek, Michael

2017-09-01

This article is directed to determining concentrations of polycyclic aromatic hydrocarbons (PAHs), which are sorbed to solid particles in the air. Pollution sources were identified on the basis of the ratio of benzo[ghi]perylene (BghiPe) to benzo[a]pyrene (BaP). Because various important information is lost by determining the simple ratio of concentrations, least squares linear regression (classic ordinary least squares regression), reduced major axis, orthogonal regression, and Kendall-Theil robust diagnostics were utilized for identification. Statistical evaluation using all aforementioned methods demonstrated different ratios of the monitored PAHs in the intervals examined during warmer and colder periods. Analogous outputs were provided by comparing gradients of the emission factors acquired from the measured concentrations of BghiPe and BaP in motor vehicle exhaust gases. Based on these outputs, it was possible plausibly to state that the influence of burning organic fuels in heating stoves is prevalent in colder periods whereas in warmer periods transport was the exclusive source because other sources of PAH emissions were not found in the examined locations. Copyright © 2017 Elsevier Ltd. All rights reserved.

Identification of a Likely Radio Counterpart to the Rapid Burster

NASA Astrophysics Data System (ADS)

Moore, Christopher B.; Rutledge, Robert E.; Fox, Derek W.; Guerriero, Robert A.; Lewin, Walter H. G.; Fender, Robert; van Paradijs, Jan

2000-04-01

We have identified a likely radio counterpart to the low-mass X-ray binary MXB 1730-335 (the Rapid Burster). The counterpart has shown 8.4 GHz radio on/off behavior correlated with the X-ray on/off behavior as observed by the RXTE/ASM during six VLA observations. The probability of an unrelated, randomly varying background source duplicating this behavior is 1%-3% depending on the correlation timescale. The location of the radio source is R.A. 17h33m24.61s, decl. -33 deg23'19.8" (J2000), +/-0.1". We do not detect 8.4 GHz radio emission coincident with type II (accretion-driven) X-ray bursts. The ratio of radio to X-ray emission during such bursts is constrained to be below the ratio observed during X-ray-persistent emission at the 2.9 σ level. Synchrotron bubble models of the radio emission can provide a reasonable fit to the full data set, collected over several outbursts, assuming that the radio evolution is the same from outburst to outburst but given the physical constraints the emission is more likely to be due to ~1 hr radio flares such as have been observed from the X-ray binary GRS 1915+105.

Identification of Major Sources of Atmospheric NH3 in an Urban Environment in Northern China During Wintertime.

PubMed

Teng, Xiaolin; Hu, Qingjing; Zhang, Leiming; Qi, Jiajia; Shi, Jinhui; Xie, Huan; Gao, Huiwang; Yao, Xiaohong

2017-06-20

To assess the relative contributions of traffic emission and other potential sources to high levels of atmospheric ammonia (NH 3 ) in urban areas in the wintertime, atmospheric NH 3 and related pollutants were measured at an urban site, ∼300 m from a major traffic road, in northern China in November and December 2015. Hourly average NH 3 varied from 0.3 to 10.8 ppb with an average of 2.4 ppb during the campaign. Contrary to the common perspective in literature, traffic emission was demonstrated to be a negligible contributor to atmospheric NH 3 . Atmospheric NH 3 correlated well with ambient water vapor during many time periods lasting from tens of hours to several days, implying NH 3 released from water evaporation is an important source. Emissions from local green space inside the urban areas were identified to significantly contribute to the observed atmospheric NH 3 during ∼60% of the sampling times. Evaporation of predeposited NH x through wet precipitation combined with emissions from local green space likely caused the spikes of atmospheric NH 3 mostly occurring 1-4 h after morning rush hours or after and during slight shower events. There are still ∼30% of the data samples with appreciable NH 3 level for which major contributors are yet to be identified.

Twenty-two emission-line AGNs from the HEAO-1 X-ray survey

NASA Technical Reports Server (NTRS)

Remillard, R. A.; Bradt, H. V. D.; Brissenden, R. J. V.; Buckley, D. A. H.; Roberts, W.; Schwartz, D. A.; Stroozas, B. A.; Tuohy, I. R.

1993-01-01

We report 22 emission-line AGN as bright, hard X-ray sources. All of them appear to be new classifications with the exception of one peculiar IRAS source which is a known quasar and has no published spectrum. This sample exhibits a rich diversity in optical spectral properties and luminosities, ranging from a powerful broad-absorption-line quasar to a weak nucleus embedded in a nearby NGC galaxy. Two cases confer X-ray luminosities in excess of 10 exp 47 erg/s. However, there is a degree of uncertainty in the X-ray identification for the AGN fainter than V about 16.5. Optically, several AGN exhibit very strong Fe II emission. One Seyfert galaxy with substantial radio flux is an exception to the common association of strong Fe II emission and radio-quiet AGN. The previously recognized IRAS quasar shows extreme velocities in the profiles of the forbidden lines; the 0 III pair is broadened to the point that the lines are blended. Several of these AGN show evidence of intrinsic obscuration, illustrating the effectiveness of hard X-ray surveys in locating AGN through high column density.

The Nature of Radio Emission from Distant Galaxies: The 1.4 GHZ Observations

NASA Astrophysics Data System (ADS)

Richards, E. A.

2000-04-01

We have conducted a deep radio survey with the Very Large Array at 1.4 GHz of a region containing the Hubble Deep Field (HDF). This survey overlaps previous observations at 8.5 GHz allowing us to investigate the radio spectral properties of microjansky sources to flux densities greater than 40 μJy at 1.4 GHz and greater than 8 μJy at 8.5 GHz. A total of 371 sources have been cataloged at 1.4 GHz as part of a complete sample within 20' of the HDF. The differential source count for this region is only marginally sub-Euclidean and is given by n(S)=(8.3+/-0.4)S-2.4+/-0.1 sr-1 Jy-1. Above about 100 μJy the radio source count is systematically lower in the HDF as compared to other fields. We conclude that there is clustering in our radio sample on size scales of 1'-40'. The 1.4 GHz-selected sample shows that the radio spectral indices are preferentially steep (α1.4=0.85) and that the sources are moderately extended with average angular size θ=1.8". Optical identification with disk-type systems at z~0.1-1 suggests that synchrotron emission, produced by supernovae remnants, is powering the radio emission in the majority of sources. The 8.5 GHz sample contains primarily moderately flat spectrum sources (α8.5=0.35), with less than 15% inverted. We argue that we may be observing an increased fraction of optically thin bremsstrahlung over synchrotron radiation in these distant star-forming galaxies.

Source contributions to PM2.5 in Guangdong province, China by numerical modeling: Results and implications

NASA Astrophysics Data System (ADS)

Yin, Xiaohong; Huang, Zhijiong; Zheng, Junyu; Yuan, Zibing; Zhu, Wenbo; Huang, Xiaobo; Chen, Duohong

2017-04-01

As one of the most populous and developed provinces in China, Guangdong province (GD) has been experiencing regional haze problems. Identification of source contributions to ambient PM2.5 level is essential for developing effective control strategies. In this study, using the most up-to-date emission inventory and validated numerical model, source contributions to ambient PM2.5 from eight emission source sectors (agriculture, biogenic, dust, industry, power plant, residential, mobile and others) in GD in 2012 were quantified. Results showed that mobile sources are the dominant contributors to the ambient PM2.5 (24.0%) in the Pearl River Delta (PRD) region, the central and most developed area of GD, while industry sources are the major contributors (21.5% 23.6%) to those in the Northeastern GD (NE-GD) region and the Southwestern GD (SW-GD) region. Although many industries have been encouraged to move from the central GD to peripheral areas such as NE-GD and SW-GD, their emissions still have an important impact on the PM2.5 level in the PRD. In addition, agriculture sources are responsible for 17.5% to ambient PM2.5 in GD, indicating the importance of regulations on agricultural activities, which has been largely ignored in the current air quality management. Super-regional contributions were also quantified and their contributions to the ambient PM2.5 in GD are significant with notable seasonal differences. But they might be overestimated and further studies are needed to better quantify the transport impacts.

40 CFR 62.11620 - Identification of plan-negative declaration.

Code of Federal Regulations, 2011 CFR

2011-07-01

... POLLUTANTS Virginia Fluoride Emissions from Existing Primary Aluminum Plants § 62.11620 Identification of... emission guidelines set forth in the Final Guideline Document for the Control of Fluoride Emissions from...

40 CFR 62.11620 - Identification of plan-negative declaration.

Code of Federal Regulations, 2010 CFR

2010-07-01

... POLLUTANTS Virginia Fluoride Emissions from Existing Primary Aluminum Plants § 62.11620 Identification of... emission guidelines set forth in the Final Guideline Document for the Control of Fluoride Emissions from...

MEMO2 - MEthane goes MObile - MEasurements and Modelling - Part 2

NASA Astrophysics Data System (ADS)

Röckmann, Thomas; Walter, Sylvia

2017-04-01

As mitigation of climate change is a key scientific and societal challenge, the 2015 United Nations Climate Change Conference in Paris (COP21) agreed to limit global warming "well below" 2˚ C and, if possible, below 1.5˚ C. Reaching this target requires massive reductions of greenhouse gas emissions, and achieving significant reduction of greenhouse gas emissions is a logical headline targets of the EU climate action and of the H2020 strategy. CH4 emissions are a major contributor to Europe's global warming impact and emissions are not well quantified yet. There are significant discrepancies between official inventories of emissions and estimates derived from direct atmospheric measurement. Effective emission reduction can only be achieved if sources are properly quantified, and mitigation efforts are verified. New advanced combinations of measurement and modelling are needed to archive such quantification. MEMO2 will contribute to the targets of the EU with a focus on methane (CH4). The project will bridge the gap between large-scale scientific estimates from in situ monitoring programs and the 'bottom-up' estimates of emissions from local sources that are used in the national reporting by I) developing new and advanced mobile methane (CH4) measurements tools and networks, II) isotopic source identification, and III) modelling at different scales. Within the project qualified scientists will be educated in the use and implementation of interdisciplinary knowledge and techniques that are essential to meet and verify emission reduction goals. MEMO2 will facilitate intensive collaboration between the largely academic greenhouse gas monitoring community and non-academic partners who are responsible for evaluating and reporting greenhouse gas emissions to policy makers. MEMO2 is a European Training Network with more than 20 collaborators from 7 countries. It is a 4-years project and we will present the project and its objectives to the scientific community to foster collaboration and scientific exchange from the beginning.

Search for the Identification of 3EG J1835+5918: Evidence for a New Type of High-Energy Gamma-Ray Source

NASA Technical Reports Server (NTRS)

Mirabal, N.; Halpern, Jules P.; Eracleous, M.; Becker, R. H.; Oliversen, Ronald (Technical Monitor)

2001-01-01

The EGRET source 3EG J1835+5918 is the brightest and most accurately positioned of the as-yet unidentified high-energy gamma-ray sources at high Galactic latitude (l, b = 89 deg, 25 deg). We present a multiwavelength study of the region around it, including X-ray, radio, and optical imaging surveys, as well as optical spectroscopic classification of most of the active objects in this area. Identifications are made of all but one of the ROSAT and ASCA sources in this region to a flux limit of approximately 5 x 10(exp -14) erg/sq cm s, which is 10(exp -4) of the gamma-ray flux. The identified X-ray sources in or near the EGRET error ellipse are radio-quiet QSOs, a galaxy cluster, and coronal emitting stars. We also find eight quasars using purely optical color selection, and we have monitored the entire field for variable optical objects on short and long time scales without any notable discoveries. The radio sources inside the error ellipse are all fainter than 4 mJy at 1.4 GHz. There are no flat-spectrum radio sources in the vicinity; the brightest neighboring radio sources are steep-spectrum radio galaxies or quasars. Since no blazar-like or pulsar-like candidate has been found as a result of these searches, 3EG J1835+5918 must be lacking one or more of the physically essential attributes of these known classes of gamma-ray emitters. If it is an AGN it lacks the beamed emission radio of blazars by at least a factor of 100 relative to identified EGRET blazars. If it is an isolated neutron star, it lacks the steady thermal X-rays from a cooling surface and the magnetospheric non-thermal X-ray emission that is characteristic of all EGRET pulsars. If a pulsar, 3EG J1835+5918 must be either older or more distant than Geminga, and probably an even more efficient or beamed gamma-ray engine. One intermittent ROSA T source falls on a blank optical field to a limit of B greater than 23.4, V greater than 23.3, and R greater than 22.5. In view of this conspicuous absence, RX J1836-2+5925 should be examined further as a candidate for identification with 3EG J1835+5918 and possibly the prototype of a new class of high-energy gamma-ray source.

An integrated system for the determination of the local, regional and long-transport contributions to Particulate Matter concentrations

NASA Astrophysics Data System (ADS)

Amodio, M.; Andriani, E.; Daresta, B. E.; de Gennaro, G.; di Gilio, A.; Ielpo, P.,; Placentino, C. M.; Trizio, L.; Tutino, M.

2010-05-01

Several epidemiological studies have shown the negative effects of air pollution on human health, which range from respiratory and cardiovascular disease to neurotoxic effects, and cancer. Most recent investigations have been focused on health toxicological features of Particulate Matter (PM) and its interactions with other pollutants: it was found that fine particles (PM2.5) could be an effective media to transport these pollutants deeply into the lung and to cause many kind of reactions which include oxidative stress, local pulmonary and systemic inflammatory responses (Künzli and Perez, 2009). Based on these implications on public health, many countries have developed plans to suggest effective control strategies which involve the identification of Particulate Matter sources, the quantitative estimation of the emission rates of the pollutants, the understanding of PM transport, mixing and transformation processes and the identification of main factors influencing PM concentrations. In this field, receptor models can be useful tools to estimate sources contributions to PM collected in an area under investigations. Different approaches to receptor model analysis can be distinguished on basis of whether chemical characteristics of emission sources are required to be known before the source apportionment. The multivariate approach could be preferred when a lack of information concerning sources profiles occurred (Hopke, 2003). In this work, the results obtained by applying an integrated approach in the monitoring of PM using several typologies of instrumentations will be shown. A prototype for the determination of the contributions of a single source (‘fugitive emission') on the fine PM concentrations has been developed: it consists of a Swam dual-channel sampler, an OPC Monitor, a sonic anemometer and a PBL Mixing monitor. The investigated site chosen for the application of prototype will be the iron and steel pole of Taranto (Apulia Region, South of Italy). Fugitive emission campaign will be performed by using three different positions around the Taranto industrial area; the main interest on Taranto is due to the presence of several activities of high impact as very wide industrial area close to the town and the numerous maritime and military activities in the harbour area (Amodio et al., 2008). The aim is to triangulate the area of the examined source on the basis of the prevalent directions of the wind. The investigation will be completed by chemical-physical characterization of PM2.5 and PM10 samples collected by the prototype in order to have additional information about the possible emissive sources. The statistical analysis, performed by Principal Component Analysis (PCA) and Positive Matrix Factorization (PMF), will be used for a detailed study of the impact of the local emissive source on the neighboring areas. Finally, the prototype will allow to identify and distinguish long range transport, regional and other local contributions on the fine PM concentrations. This work was supported by the Strategic Project PS_122 founded by Apulia Region. References Künzli, N., Perez, L., 2009. Swiss Medical Weekly 139(17-18), 242-250. Hopke, P.K., 2003. Journal of Chemometrics 17(5), 255-265. Amodio, M., Caselli, M., Daresta, B.E., de Gennaro, G., Ielpo, P., Placentino, C.M., Tutino, 2008. Chemical Engineering Transactions 16, 193-199.

Project identification for methane reduction options

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

Kerr, T.

1996-12-31

This paper discusses efforts directed at reduction in emission of methane to the atmosphere. Methane is a potent greenhouse gas, which on a 20 year timeframe may present a similar problem to carbon dioxide. In addition, methane causes additional problems in the form of smog and its longer atmospheric lifetime. The author discusses strategies for reducing methane emission from several major sources. This includes landfill methane recovery, coalbed methane recovery, livestock methane reduction - in the form of ruminant methane reduction and manure methane recovery. The author presents examples of projects which have implemented these ideas, the economics of themore » projects, and additional gains which come from the projects.« less

Enhancing weak transient signals in SEVIRI false color imagery: Application to dust source detection in southern Africa

NASA Astrophysics Data System (ADS)

Murray, J. E.; Brindley, H. E.; Bryant, R. G.; Russell, J. E.; Jenkins, K. F.; Washington, R.

2016-09-01

A method is described to significantly enhance the signature of dust events using observations from the Spinning Enhanced Visible and InfraRed Imager (SEVIRI). The approach involves the derivation of a composite clear-sky signal for selected channels on an individual time step and pixel basis. These composite signals are subtracted from each observation in the relevant channels to enhance weak transient signals associated with either (a) low levels of dust emission or (b) dust emissions with high salt or low quartz content. Different channel combinations, of the differenced data from the steps above, are then rendered in false color imagery for the purpose of improved identification of dust source locations and activity. We have applied this clear-sky difference (CSD) algorithm over three (globally significant) source regions in southern Africa: the Makgadikgadi Basin, Etosha Pan, and the Namibian and western South African coast. Case study analyses indicate three notable advantages associated with the CSD approach over established image rendering methods: (i) an improved ability to detect dust plumes, (ii) the observation of source activation earlier in the diurnal cycle, and (iii) an improved ability to resolve and pinpoint dust plume source locations.

Development and application of a Controlled Release Facility (CRF) to validate flux quantifying methodologies.

NASA Astrophysics Data System (ADS)

Helmore, Jonathan

2017-04-01

The National Physical Laboratory, the UK's National Measurement Institute, has developed a novel facility capable of replicating the gaseous emission flux characteristics of a variety of real-word scenarios as may be found in small to medium scale industry and agriculture. The Controlled Release Facility (CRF) can be used to challenge conventional remote sensing techniques, as well as validate new Unmanned Aerial Vehicle (UAV) and distributed sensor network based methods, for source identification and flux calculation. The CRF method will be described and the results from three case studies will be discussed: The replication of an operational on-shore shale gas well using emissions of natural gas to atmosphere and measurements using Differential Absorption LIDAR (DIAL); the replication of fugitive volatile organic compounds emissions from a petrochemical unit and measurements using DIAL; and the replication of methane and carbon dioxide emissions from landfill and measurements using both fixed wing and multi-rotor UAVs.

High-resolution spectra of the 3.29 micron interstellar emission feature - A summary

NASA Technical Reports Server (NTRS)

Tokunaga, A. T.; Sellgren, K.; Smith, R. G.; Nagata, T.; Sakata, A.; Nakada, Y.

1991-01-01

High spectral resolution observations of the 3.29-micron interstellar emission feature show two types of profiles. Type 1 has a central wavelength of 3.289-micron and is observed in extended objects such as planetary nebulae and H II regions. Type 2 has a central wavelength of 3.296 microns and is observed around a small number of stellar sources. Type 2 has a full width at half-maximum of 0.020 micron; Type 1 has a broader FWHM, perhaps as much as 0.042 micron, but this is uncertain because of contamination by Pf(delta) emission. These profiles are tabulated for comparison to laboratory data. It is found that no proposed identification for the 3.29-micron emission feature definitely matches the observational spectra, although amorphous aromatic materials and heated polycyclic aromatic hydrocarbons tend to fit the best.

Search for the Identification of 3EG J1835+5918: Evidence for a New Type of High-Energy Gamma-Ray Source?

NASA Technical Reports Server (NTRS)

Mirabal, N.; Halpern, Jules P.; Eracleous, M.; Becker, R. H.; Oliversen, Ronald (Technical Monitor)

2001-01-01

Most of the EGRET high-energy gamma-ray sources remain unidentified. It is highly likely that many of these are fainter blazars or pulsars, but there may also be new types of sources to be discovered. We have focussed our search for novel gamma-ray sources on 3EG 1835+5918, which is the brightest and most accurately positioned of the unidentified EGRET sources at high Galactic latitude (l, b = 89 deg, 25 deg). In this talk, we will summarize the results of X-ray, radio, and optical surveys of this location. In particular, we have made complete optical identifications of all of the ROSAT and ASCA sources in this region to a flux limit of approximately 1 x 10(exp -13) ergs/sq cm s. All of the X-ray sources within the EGRET error circle are radio-quiet quasars or coronally emitting stars. Previous radio pulsar searches have been unsuccessful. We set an upper limit of 3.8 mJy (at 1.4 GHz) on any possible radio counterpart to 3EG 1835+5918. We also find several quasars and white dwarfs using optical color selection, and we have monitored the entire field for variable optical objects on short and long time scales. Since no blazar-like or pulsar-like candidate has been found as a result of these searches, we assert that 3EG 1835+5918 must be lacking in one or more of the physically essential attributes of those classes of gamma-ray emitters. In particular, its radio flux is at least two orders of magnitude fainter than any of the securely identified EGRET blazars, and its soft X-ray flux is at least 30 times fainter than that of Geminga and other EGRET pulsars. If it is an AGN it lacks the beamed radio emission of blazars. If it is an isolated neutron star, it lacks both the thermal X-rays from a cooling surface and the magnetospheric non-thermal X-ray emission that is characteristic of all EGRET pulsars. As such, it is more problematic physically than Geminga, which is an ordinary pulsar that only lacks radio emission. As a pulsar, 3EG 1835+5918 would have to be either older or more distant than Geminga, and probably an even more efficient gamma-ray engine.

Sources of fine particles in the South Coast area, California

NASA Astrophysics Data System (ADS)

Kim, Eugene; Turkiewicz, Katarzyna; Zulawnick, Sylvia A.; Magliano, Karen L.

2010-08-01

PM 2.5 (particulate matter less than 2.5 μm in aerodynamic diameter) speciation data collected between 2003 and 2005 at two United State Environmental Protection Agency (US EPA) Speciation Trends Network monitoring sites in the South Coast area, California were analyzed to identify major PM 2.5 sources as a part of the State Implementation Plan development. Eight and nine major PM 2.5 sources were identified in LA and Rubidoux, respectively, through PMF2 analyses. Similar to a previous study analyzing earlier data ( Kim and Hopke, 2007a), secondary particles contributed the most to the PM 2.5 concentrations: 53% in LA and 59% in Rubidoux. The next highest contributors were diesel emissions (11%) in LA and Gasoline vehicle emissions (10%) in Rubidoux. Most of the source contributions were lower than those from the earlier study. However, the average source contributions from airborne soil, sea salt, and aged sea salt in LA and biomass smoke in Rubidoux increased. To validate the apportioned sources in this study, PMF2 results were compared with those obtained from EPA PMF ( US EPA, 2005). Both models identified the same number of major sources and the resolved source profiles and contributions were similar at the two monitoring sites. The minor differences in the results caused by the differences in the least square algorithm and non-negativity constraints between two models did not affect the source identifications.

The optical counterpart of GX 339-4, a possible black hole X-ray source

NASA Technical Reports Server (NTRS)

Grindlay, J. E.

1979-01-01

Optical studies of the galactic X-ray source GX 339-4 (4U 1658-48), which led to its recent identification as reported by Doxsey et al. (1979), are presented. Reddening and distance estimates are given, as well as evidence for optical variability on differing time scales. The emission-line spectra and UBV photometry suggest that GX 339-4 may be at about 8 kpc and have a main-sequence B star binary companion. Both the optical spectrum and optical/X-ray luminosity ratio for GX 339-4 may be similar to Cir X-1.

X-ray Measurements of a Thermo Scientific P385 DD Neutron Generator

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

E.H. Seabury; D.L. Chichester; A.J. Caffrey

2001-08-01

Idaho National Laboratory is experimenting with electrical neutron generators, as potential replacements for californium-252 radioisotopic neutron sources in its PINS prompt gamma-ray neutron activation analysis (PGNAA) system for the identification of military chemical warfare agents and explosives. In addition to neutron output, we have recently measured the x-ray output of the Thermo Scientific P385 deuterium-deuterium neutron generator. X-rays are a normal byproduct from a neutron generator and depending on their intensity and energy they can interfere with gamma rays from the object under test, increase gamma-spectrometer dead time, and reduce PGNAA system throughput. The P385 x-ray energy spectrum was measuredmore » with a high-purity germanium (HPGe) detector, and a broad peak is evident at about 70 keV. To identify the source of the x-rays within the neutron generator assembly, it was scanned by collimated scintillation detectors along its long axis. At the strongest x-ray emission points, the generator also was rotated 60° between measurements. The scans show the primary source of x-ray emission from the P385 neutron generator is an area 60 mm from the neutron production target, in the vicinity of the ion source. Rotation of the neutron generator did not significantly alter the x-ray count rate, and the x-ray emission appears to be axially symmetric within the neutron generator.« less

Quantifying Black Carbon emissions in high northern latitudes using an Atmospheric Bayesian Inversion

NASA Astrophysics Data System (ADS)

Evangeliou, Nikolaos; Thompson, Rona; Stohl, Andreas; Shevchenko, Vladimir P.

2016-04-01

Black carbon (BC) is the main light absorbing aerosol species and it has important impacts on air quality, weather and climate. The major source of BC is incomplete combustion of fossil fuels and the burning of biomass or bio-fuels (soot). Therefore, to understand to what extent BC affects climate change and pollutant dynamics, accurate knowledge of the emissions, distribution and variation of BC is required. Most commonly, BC emission inventory datasets are built by "bottom up" approaches based on activity data and emissions factors, but these methods are considered to have large uncertainty (Cao et al, 2006). In this study, we have used a Bayesian Inversion to estimate spatially resolved BC emissions. Emissions are estimated monthly for 2014 and over the domain from 180°W to 180°E and 50°N to 90°N. Atmospheric transport is modeled using the Lagrangian Particle Dispersion Model, FLEXPART (Stohl et al., 1998; 2005), and the inversion framework, FLEXINVERT, developed by Thompson and Stohl, (2014). The study domain is of particular interest concerning the identification and estimation of BC sources. In contrast to Europe and North America, where BC sources are comparatively well documented as a result of intense monitoring, only one station recording BC concentrations exists in the whole of Siberia. In addition, emissions from gas flaring by the oil industry have been geographically misplaced in most emission inventories and may be an important source of BC at high latitudes since a significant proportion of the total gas flared occurs at these high latitudes (Stohl et al., 2013). Our results show large differences with the existing BC inventories, whereas the estimated fluxes improve modeled BC concentrations with respect to observations. References Cao, G. et al. Atmos. Environ., 40, 6516-6527, 2006. Stohl, A. et al. Atmos. Environ., 32(24), 4245-4264, 1998. Stohl, A. et al. Atmos. Chem. Phys., 5(9), 2461-2474, 2005. Stohl, A. et al. Atmos. Chem. Phys., 13, 8833-8855, 2013. Thompson, R. L., and Stohl A. Geosci. Model Dev., 7, 2223-2242, 2014.

Greenhouse Gas (GHG) Source Detection and Attribution in the San Francisco Bay Area of California Using a Mobile Measurement Platform

NASA Astrophysics Data System (ADS)

Guha, A.; Bower, J.; Martien, P. T.; Perkins, I.; Randall, S.; Stevenson, E.; Young, A.; Hilken, H.

2016-12-01

The Bay Area Air Quality Management District is the greater San Francisco Bay metropolitan area's chief air quality regulatory agency. Aligning itself with the Governor's Executive Order S-3-05, the Air District has set a goal to reduce the region's GHG emissions by 80% below 1990 levels by the year 2050. The Air District's 2016 Clean Air Plan will lay out the agency's vision and actions to put the region on a path forward towards achieving the 2050 goal while also reducing air pollution and related health impacts. The 2016 Plan has three overarching objectives: 1) develop a multi-pollutant emissions control strategy, (2) reduce population exposure to harmful air pollutants, especially in vulnerable communities, and (3) protect climate through a comprehensive Regional Climate Protection Strategy. To accomplish one of 2016 Plan's control measures (SL3 - Greenhouse Gas Monitoring and Measurement Network), the Air District has fabricated a mobile measurement platform i.e. a GHG research van to perform targeted CH4 emissions hotspot detection and source attribution. The van is equipped with analyzers capable of measuring CH4, CO2 and N2O in ambient plumes at fast sampling rates. The coincident measurement of source tracers like isotopic methane (13C - CH4), CO and ethane (C2H6) provide the capability to distinguish between biogenic, combustion-based and fossil-based fugitive methane sources, respectively. The GHG research van is a comprehensive mobile tool to perform tracer-based GHG source identification and apportionment. We report observation-based source-specific tracer-to-tracer emission ratios from a region-wide survey of well-known area sources like landfills, wastewater treatment facilities and dairies, and compare those with similar ratios in the Air District's GHG inventory. We also investigate plumes from potentially under-inventoried sources like anaerobic digesters, composting operations, active and plugged oil and gas wells, and a natural gas storage facility. Data from source-specific measurements will lead to an improved understanding of GHG emissions from well-known and lesser-known CH4 sources in the region, which is key in resolving the differences between top-down regional estimates (Fairley and Fischer, 2015; Jeong et al., in prep) and the regional bottom-up inventory.

Direct Roadside Measurements of Volatile Organic Compounds in Vehicle Emissions Using NO+ Time-of-Flight Chemical Ionization Mass Spectrometry

NASA Astrophysics Data System (ADS)

Warneke, C.; Finewax, Z.; Koss, A.; Coggon, M.; Gilman, J.; Ziemann, P. J.; De Gouw, J. A.

2017-12-01

Vehicle emissions are a large source of volatile organic compounds (VOCs) in urban areas. As vehicle emissions have strongly decreased over the last few decades, several studies have shown that a relatively small fraction of vehicles are now responsible for total mobile emissions. While tunnel studies have measured on-road vehicular emissions representative of a vehicular fleet, there is limited data describing vehicle-specific, on-road VOC profiles. In this study VOCs were measured in real-time at one-second time resolution using NO+ time-of-flight chemical ionization mass spectrometry (NO+ ToF-CIMS) on a Denver Metro freeway ramp for several hours in the summer of 2016 and on Highway 7, east of Boulder, Colorado, in the summer of 2017. With this setup plumes from single vehicles were successfully measured. Using positive matrix factorization (PMF), three VOC sources were obtained from the data: gasoline vapor, gasoline exhaust and diesel exhaust, which were validated by laboratory samples of gasoline and diesel headspace, of vehicle exhaust and from literature. Chemical identification of the PMF factors was further aided by authentic samples of canisters via improved Whole Air Sampling (iWAS) and Gas Chromatography - NO+ ToF-CIMS. A small portion of total vehicles measured had VOC emissions greatly exceeding the average vehicle sampled. These high-emitting vehicles will be investigated to determine the relative importance of high-emitting vehicles to overall emissions in urban areas, and how the emissions composition of high-emitting vehicles is different from the average vehicle.

Primary Emission and the Potential of Secondary Aerosol Formation from Chinese Gasoline Engine Exhaust

NASA Astrophysics Data System (ADS)

Hu, Min; Peng, Jianfei; Qin, Yanhong; Du, Zhuofei; Li, Mengjin; Zheng, Rong; Zheng, Jing; Shang, Dongjie; Lu, Sihua; Wu, Yusheng; Zeng, Limin; Guo, Song; Shao, Min; Wang, Yinhui; Shuai, Shijin

2017-04-01

Along with the urbanization and economic growth, vehicle population in China reached 269 million, ranked the second in the world in 2015. Gasoline vehicle is identified to be the main source for urban PM2.5 in China, accounting for 15%-31%. In this study the impact of fuel components on PM2.5 and volatile organic compounds (VOCs) emissions from a gasoline port fuel injection (PFI) engine and a gasoline direct injection (GDI) engine are discussed. Results show that, higher proportion of aromatics, alkenes or sulfur in gasoline fuel will lead to higher PM emissions. The PM from the PFI engine mainly consists of OC and a small amount of EC and inorganic ions, while the PM discharge from the GDI engine mainly consists of EC, OM and a small amount of inorganic ions. Since the GDI engines can reduce fuel consumption and CO2 emissions, and it would become more and more popular in the near future. The characteristics of POM component, emission factors and source profile were investigated from GDI engine, particularly focused on the effect of engine speed, load and the catalyst, which will be very much helpful for source identification as source indicators. Chamber experiments were conducted to quantify the potential of secondary aerosol formation from exhaust of a PFI gasoline engine and China V gasoline fuel. During 4-5 h simulation, equivalent to10 days of atmospheric photo-oxidation in Beijing, the extreme SOA production was 426 ± 85 mg/kg fuel, with high precursors and OH exposure. 14% of SOA measured in the chamber experiments could be explained through the oxidation of speciated single-ring aromatics. Unspeciated precursors, such as intermediate-volatility organic compounds and semi-volatility organic compounds, might be significant for SOA formation from gasoline VOCs. We concluded that reduction of emissions of aerosol precursor gases from vehicles is essential to mediate pollution in China.

Source origin of trace elements in PM from regional background, urban and industrial sites of Spain

NASA Astrophysics Data System (ADS)

Querol, X.; Viana, M.; Alastuey, A.; Amato, F.; Moreno, T.; Castillo, S.; Pey, J.; de la Rosa, J.; Sánchez de la Campa, A.; Artíñano, B.; Salvador, P.; García Dos Santos, S.; Fernández-Patier, R.; Moreno-Grau, S.; Negral, L.; Minguillón, M. C.; Monfort, E.; Gil, J. I.; Inza, A.; Ortega, L. A.; Santamaría, J. M.; Zabalza, J.

Despite their significant role in source apportionment analysis, studies dedicated to the identification of tracer elements of emission sources of atmospheric particulate matter based on air quality data are relatively scarce. The studies describing tracer elements of specific sources currently available in the literature mostly focus on emissions from traffic or large-scale combustion processes (e.g. power plants), but not on specific industrial processes. Furthermore, marker elements are not usually determined at receptor sites, but during emission. In our study, trace element concentrations in PM 10 and PM 2.5 were determined at 33 monitoring stations in Spain throughout the period 1995-2006. Industrial emissions from different forms of metallurgy (steel, stainless steel, copper, zinc), ceramic and petrochemical industries were evaluated. Results obtained at sites with no significant industrial development allowed us to define usual concentration ranges for a number of trace elements in rural and urban background environments. At industrial and traffic hotspots, average trace metal concentrations were highest, exceeding rural background levels by even one order of magnitude in the cases of Cr, Mn, Cu, Zn, As, Sn, W, V, Ni, Cs and Pb. Steel production emissions were linked to high levels of Cr, Mn, Ni, Zn, Mo, Cd, Se and Sn (and probably Pb). Copper metallurgy areas showed high levels of As, Bi, Ga and Cu. Zinc metallurgy was characterised by high levels of Zn and Cd. Glazed ceramic production areas were linked to high levels of Zn, As, Se, Zr, Cs, Tl, Li, Co and Pb. High levels of Ni and V (in association) were tracers of petrochemical plants and/or fuel-oil combustion. At one site under the influence of heavy vessel traffic these elements could be considered tracers (although not exclusively) of shipping emissions. Levels of Zn-Ba and Cu-Sb were relatively high in urban areas when compared with industrialised regions due to tyre and brake abrasion, respectively.

X-ray Studies of Unidentified Galactic TeV Gamma-ray Sources

NASA Astrophysics Data System (ADS)

Pühlhofer, Gerd

2009-05-01

Many of the recently discovered Galactic TeV sources remain unidentified to date. A large fraction of the sources is possibly associated with relic pulsar wind nebula (PWN) systems. One key question here is the maximum energy (beyond TeV) attained in the compact PWNe. Hard X-ray emission can trace those particles, but current non-focussing X-ray instruments above 10 keV have difficulties to deconvolve the hard pulsar spectrum from its surrounding nebula. Some of the new TeV sources are also expected to originate from middle-aged and possibly even from old supernova remnants (SNR). But no compelling case for such an identification has been found yet. In established young TeV-emitting SNRs, X-ray imaging above 10 keV could help to disentangle the leptonic from the hadronic emission component in the TeV shells, if secondary electrons produced in hadronic collisions can be effectively detected. As SNRs get older, the high energy electron component is expected to fade away. This may allow to verify the picture through X-ray spectral evolution of the source population. Starting from the lessons we have learned so far from X-ray follow-up observations of unidentified TeV sources, prospects for Simbol-X to resolve open questions in this field will be discussed.

The ALMA Frontier Fields Survey. III. 1.1 mm emission line identifications in Abell 2744, MACSJ 0416.1-2403, MACSJ 1149.5+2223, Abell 370, and Abell S1063

NASA Astrophysics Data System (ADS)

González-López, J.; Bauer, F. E.; Aravena, M.; Laporte, N.; Bradley, L.; Carrasco, M.; Carvajal, R.; Demarco, R.; Infante, L.; Kneissl, R.; Koekemoer, A. M.; Muñoz Arancibia, A. M.; Troncoso, P.; Villard, E.; Zitrin, A.

2017-12-01

Context. Most sub-mm emission line studies of galaxies to date have targeted sources with known redshifts where the frequencies of the lines are well constrained. Recent blind line scans circumvent the spectroscopic redshift requirement, which could represent a selection bias. Aims: Our aim is to detect emission lines present in continuum oriented observations. The detection of these lines provides spectroscopic redshift information and yields important properties of the galaxies. Methods: We perform a search for emission lines in the Atacama Large Millimeter/submillimeter Array observations of five clusters which are part of the Frontier Fields and assess the reliability of our detection. We additionally investigate plausibility by associating line candidates with detected galaxies in deep near-infrared imaging. Results: We find 26 significant emission lines candidates, with observed line fluxes between 0.2-4.6 Jy kms-1and velocity dispersions (FWHM) of 25-600kms-1. Nine of these candidates lie in close proximity to near-infrared sources, boosting their reliability; in six cases the observed line frequency and strength are consistent with expectations given the photometric redshift and properties of the galaxy counterparts. We present redshift identifications, magnifications, and molecular gas estimates for the galaxies with identified lines. We show that two of these candidates likely originate from starburst galaxies, one of which is a so-called jellyfish galaxy that is strongly affected by ram pressure stripping, while another two are consistent with being main sequence galaxies based in their depletion times. Conclusions: This work highlights the degree to which serendipitous emission lines can be discovered in large mosaic continuum observations when deep ancillary data are available. The low number of high-significance line detections, however, confirms that such surveys are not as optimal as blind line scans. We stress that Monte Carlo simulations should be used to assess the line detection significances since using the negative noise suffers from stochasticity and incurs significantly larger uncertainties.

Modeling of pesticide emissions from agricultural ecosystems

NASA Astrophysics Data System (ADS)

Li, Rong

2012-04-01

Pesticides are applied to crops and soils to improve agricultural yields, but the use of pesticides has become highly regulated because of concerns about their adverse effects on human health and environment. Estimating pesticide emission rates from soils and crops is a key component for risk assessment for pesticide registration, identification of pesticide sources to the contamination of sensitive ecosystems, and appreciation of transport and fate of pesticides in the environment. Pesticide emission rates involve processes occurring in the soil, in the atmosphere, and on vegetation surfaces and are highly dependent on soil texture, agricultural practices, and meteorology, which vary significantly with location and/or time. To take all these factors into account for simulating pesticide emissions from large agricultural ecosystems, this study coupled a comprehensive meteorological model with a dynamic pesticide emission model. The combined model calculates hourly emission rates from both emission sources: current applications and soil residues resulting from historical use. The coupled modeling system is used to compute a gridded (36 × 36 km) hourly toxaphene emission inventory for North America for the year 2000 using a published U.S. toxaphene residue inventory and a Mexican toxaphene residue inventory developed using its historical application rates and a cropland inventory. To my knowledge, this is the first such hourly toxaphene emission inventory for North America. Results show that modeled emission rates have strong diurnal and seasonal variations at a given location and over the entire domain. The simulated total toxaphene emission from contaminated agricultural soils in North America in 2000 was about 255 t, which compares reasonably well to a published annual estimate. Most emissions occur in spring and summer, with domain-wide emission rates in April, May and, June of 36, 51, and 35 t/month, respectively. The spatial distribution of emissions depends on the distribution of toxaphene soil residues, and high emission rates coincide with heavily contaminated areas.

Historical emissions critical for mapping decarbonization pathways

NASA Astrophysics Data System (ADS)

Majkut, J.; Kopp, R. E.; Sarmiento, J. L.; Oppenheimer, M.

2016-12-01

Policymakers have set a goal of limiting temperature increase from human influence on the climate. This motivates the identification of decarbonization pathways to stabilize atmospheric concentrations of CO2. In this context, the future behavior of CO2 sources and sinks define the CO2 emissions necessary to meet warming thresholds with specified probabilities. We adopt a simple model of the atmosphere-land-ocean carbon balance to reflect uncertainty in how natural CO2 sinks will respond to increasing atmospheric CO2 and temperature. Bayesian inversion is used to estimate the probability distributions of selected parameters of the carbon model. Prior probability distributions are chosen to reflect the behavior of CMIP5 models. We then update these prior distributions by running historical simulations of the global carbon cycle and inverting with observationally-based inventories and fluxes of anthropogenic carbon in the ocean and atmosphere. The result is a best-estimate of historical CO2 sources and sinks and a model of how CO2 sources and sinks will vary in the future under various emissions scenarios, with uncertainty. By linking the carbon model to a simple climate model, we calculate emissions pathways and carbon budgets consistent with meeting specific temperature thresholds and identify key factors that contribute to remaining uncertainty. In particular, we show how the assumed history of CO2 emissions from land use change (LUC) critically impacts estimates of the strength of the land CO2 sink via CO2 fertilization. Different estimates of historical LUC emissions taken from the literature lead to significantly different parameterizations of the carbon system. High historical CO2 emissions from LUC lead to a more robust CO2 fertilization effect, significantly lower future atmospheric CO2 concentrations, and an increased amount of CO2 that can be emitted to satisfy temperature stabilization targets. Thus, in our model, historical LUC emissions have a significant impact on allowable carbon budgets under temperture targets.

Hexabromocyclododecanes (HBCDDs) in surface soils from coastal cities in North China: Correlation between diastereoisomer profiles and industrial activities.

PubMed

Zhang, Yueqing; Li, Qifeng; Lu, Yonglong; Jones, Kevin; Sweetman, Andrew J

2016-04-01

Hexabromocyclododecane (HBCDD) is a brominated flame retardant with a wide range of industrial applications, although little is known about its patterns of spatial distribution in soils in relation to industrial emissions. This study has undertaken a large-scale investigation around an industrialized coastal area of China, exploring the concentrations, spatial distribution and diastereoisomer profiles of HBCDD in 188 surface soils from 21 coastal cities in North China. The detection frequency was 100% and concentrations of total HBCDD in the surface soils ranged from 0.123 to 363 ng g(-1) and averaged 7.20 ng g(-1), showing its ubiquitous existence at low levels. The spatial distribution of HBCDD exhibited a correlation with the location of known manufacturing facilities in Weifang, suggesting the production of HBCDD as major emission source. Diastereoisomer profiles varied in different cities. Diastereoisomer compositions in soils were compared with emissions from HBCDD industrial activities, and correlations were found between them, which has the potential for source identification. Although the contemporary concentrations of HBCDD in soils from the study were relatively low, HBCDD-containing products (expanded/extruded polystyrene insulation boards) would be a potential source after its service life, and attention needs to be paid to prioritizing large-scale waste management efforts. Copyright © 2016 Elsevier Ltd. All rights reserved.

NARROW-LINE X-RAY-SELECTED GALAXIES IN THE CHANDRA -COSMOS FIELD. I. OPTICAL SPECTROSCOPIC CATALOG

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

Pons, E.; Watson, M. G.; Elvis, M.

2016-04-20

The COSMOS survey is a large and deep survey with multiwavelength observations of sources from X-rays to the UV, allowing an extensive study of their properties. The central 0.9 deg{sup 2} of the COSMOS field have been observed by Chandra with a sensitivity up to 1.9 × 10{sup −16} erg cm{sup −2} s{sup −1} in the full (0.5–10 keV) band. Photometric and spectroscopic identification of the Chandra -COSMOS (C-COSMOS) sources is available from several catalogs and campaigns. Despite the fact that the C-COSMOS galaxies have a reliable spectroscopic redshift in addition to a spectroscopic classification, the emission-line properties of thismore » sample have not yet been measured. We present here the creation of an emission-line catalog of 453 narrow-line sources from the C-COSMOS spectroscopic sample. We have performed spectral fitting for the more common lines in galaxies ([O ii] λ 3727, [Ne iii] λ 3869, H β , [O iii] λλ 4959, 5007, H α , and [N ii] λλ 6548, 6584). These data provide an optical classification for 151 (i.e., 33%) of the C-COSMOS narrow-line galaxies based on emission-line diagnostic diagrams.« less

Methane emission during municipal wastewater treatment.

PubMed

Daelman, Matthijs R J; van Voorthuizen, Ellen M; van Dongen, Udo G J M; Volcke, Eveline I P; van Loosdrecht, Mark C M

2012-07-01

Municipal wastewater treatment plants emit methane. Since methane is a potent greenhouse gas that contributes to climate change, the abatement of the emission is necessary to achieve a more sustainable urban water management. This requires thorough knowledge of the amount of methane that is emitted from a plant, but also of the possible sources and sinks of methane on the plant. In this study, the methane emission from a full-scale municipal wastewater facility with sludge digestion was evaluated during one year. At this plant the contribution of methane emissions to the greenhouse gas footprint were slightly higher than the CO₂ emissions related to direct and indirect fossil fuel consumption for energy requirements. By setting up mass balances over the different unit processes, it could be established that three quarters of the total methane emission originated from the anaerobic digestion of primary and secondary sludge. This amount exceeded the carbon dioxide emission that was avoided by utilizing the biogas. About 80% of the methane entering the activated sludge reactor was biologically oxidized. This knowledge led to the identification of possible measures for the abatement of the methane emission. Copyright © 2012 Elsevier Ltd. All rights reserved.

Fevers and Chills: Separating thermal and synchrotron components in SNR spectra

NASA Astrophysics Data System (ADS)

Fedor, Emily Elizabeth; Martina-Hood, Hyourin; Stage, Michael D.

2018-06-01

Spatially-resolved spectroscopy is an extremely powerful tool in X-ray analysis of extended sources, but can be computationally difficult if a source exhibits complex morphology. For example, high-resolution Chandra data of bright Galactic supernova remnants (Cas A, Tycho, etc.) allow extractions of high-quality spectra from tens to hundreds of thousands of regions, providing a rich laboratory for localizing emission from processes such as thermal line emission, bremsstrahlung, and synchrotron. This soft-band analysis informs our understanding of the typically nonthermal hard X-ray emission observed with other lower-resolution instruments. The analysis is complicated by both projection effects and the presence of multiple emission mechanisms in some regions. In particular, identifying regions with significant nonthermal emission is critical to understanding acceleration processes in remnants. Fitting tens of thousands of regions with complex, multi-component models can be time-consuming and involve so many free parameters that little constraint can be placed on the values. Previous work by Stage & Allen ('06, '07, '11) on Cas A used a technique to identify regions dominated by the highest-cutoff synchrotron emission by fitting with a simple thermal emission model and identifying regions with anomalously high apparent temperatures (caused by presence of the high-energy tail of the synchrotron emission component). Here, we present a similar technique. We verify the previous approach and, more importantly, expand it to include a method to identify regions containing strong lower-cutoff synchrotron radiation. Such regions might be associated with the reverse-shock of a supernova. Identification of a nonthermal electron population in the interior of an SNR would have significant implications for the energy balance and emission mechanisms producing the high-energy (> 10 keV) spectrum.

VizieR Online Data Catalog: RASS-6dFGS catalogue (Mahony+, 2010)

NASA Astrophysics Data System (ADS)

Mahony, E. K.; Croom, S. M.; Boyle, B. J.; Edge, A. C.; Mauch, T.; Sadler, E. M.

2014-09-01

Objects were selected such that the dominant source of X-ray emission originates from an AGN. The target list was selected from the southern sources (δ<=0°) of the RBSC, a total of 9578 sources. Sources were then checked for optical identifications via a visual inspection process using Digitized Sky Survey (DSS) images. The majority of the optical positions were taken from the United States Naval Observatory (USNO) data base, with the remainder taken from either the Automated Plate Measuring (APM) or DSS catalogues. Positions from these latter catalogues were used when the USNO appeared to give an incorrect position according to the DSS images. Optical magnitudes were taken from the USNO-A2.0 catalogue (Monet 1998, Cat. I/252). (2 data files).

Methane Emissions from Kuwait: long-term measurement, mobile plume mapping and isotopic characterisation

NASA Astrophysics Data System (ADS)

al-Shalaan, Aalia; Lowry, David; Fisher, Rebecca; Zazzeri, Giulia; Alsarawi, Mohammad; Nisbet, Euan

2017-04-01

National and EDGAR inventories suggest that the dominant sources of methane in Kuwait are leaks from gas flaring and distribution (92%) and landfills (5%),with additional smaller emissions from sewage (wastewater) treatment and ruminant animals. New measurements during 2015 and 2016 suggest that the inventories differ greatly from observations. Regular weekly bag samples have been collected from 3 sites in Kuwait, one NW of the city, one to the SE and one in the city from the rooftop of Kuwait College of Science. These take turns to have the highest recorded mole fractions, depending on wind direction. Associated with higher mole fraction is a consistent depletion in 13C of methane, pointing to a national source mix with 13C of -54.8‰. This is significantly different from the calculation using inventories that suggest a mix of -51.3‰. Mobile plume identification using a Picarro G2301 analyser, coupled with Tedlar bag sampling for isotopic analysis (Zazzeri et al., 2015), reveals that by far the largest observed source of methane in Kuwait is from landfill sites (13C of -57‰), with smaller contributions from fossil fuel industry (-51‰), wastewater treatment (-50‰) and ruminant animals (cows, -62‰; camels -60‰, sheep -64‰). Many of these isotopic signatures are close to those observed for the same source categories in other countries, for example landfill emission signatures have the same range as those calculated for UK and Hong Kong (-60 to -55‰), even to the level that older closed and capped landfills emit smaller amounts of methane at more enriched values (-55 to -50‰), due to small % of topsoil oxidation. Our findings suggest that many more top down measurements must be made to verify emissions inventories, particularly in middle eastern countries where a significant proportion of emissions are unverified calculations of fossil fuel emissions. Zazzeri, G. et al. (2015) Plume mapping and isotopic characterization of anthropogenic methane sources, Atmospheric Environment, 110, 151-162, doi.org/10.1016/j.atmosenv.2015.03.029

Emission of Polychlorinated Naphthalenes during Thermal Related Processes

NASA Astrophysics Data System (ADS)

Liu, Guorui; Zheng, Minghui; Du, Bing; Liu, Wenbin; Zhang, Bing; Xiao, Ke

2010-05-01

Due to the structural similarity of polychlorinated naphthalenes (PCNs) to those of dioxins, PCNs exhibit toxicological properties similar to dioxins (Olivero-Verbel et al., 2004). Based on their high toxicity, persistence, bioaccumulation, and long-distance transmission, PCNs were also selected as a candidate POP for the UN-ECE (United Nations Economic Commission for Europe) POP protocol (Lerche et al., 2002). In addition, some studies suggested that PCNs contributed a greater proportion of the dioxin-like activity than polychlorinated biphenyls (PCBs) and polychlorinated dibenzo-p-dioxins/dibenzofurans (PCDD/Fs) contributed in some locations (Kannan et al., 1998). However, the identification and quantitation for PCN sources are very scarce compared with PCDD/Fs. Understanding the emission levels and developing the emission inventory of PCNs is important for regulatory and source reduction purposes. In this study, several potential sources were preliminarily investigated for PCN release. Coking process (CP), iron ore sintering (IOS), and electric arc furnace steel making units (AF) were selected due to their huge activity level of industrial production in China. Municipal solid waste incineration (MSWI) and medical waste incineration (MWI) were also investigated because of the possible high concentration of PCNs in stack gas. Two plants were investigated for each thermal related process, except for MWI with one incinerator was investigated. The stack gas samples were collected by automatic isokinetic sampling system (Isostack Basic, TCR TECORA, Milan Italy). Isotope dilution high resolution gas chromatography coupled with high resolution mass spectrometry (HRGC/HRMS) technique was used for the identification and quantitation of PCN congeners. The concentrations of PCNs from the selected thermal processes were determined in this study. The average concentrations of total PCNs were 26 ng Nm-3 for CP, 65 ng Nm-3 for IOS, 720 ng Nm-3 for AF, 443 ng Nm-3 for MSWI, and 45 ng Nm-3 for MWI. The emission factors of PCNs were derived, and the average values were 6 μg tonne-1 for CP, 42 μg tonne-1 for IOS, 2980 μg tonne-1 for AF, 1354 μg tonne-1 for MSWI, and 937 μg tonne-1 for MWI, which could be helpful for estimating the annual emission amounts of PCNs from the investigated sources. However, since the investigated plant numbers for each process are limited, there might be large uncertainties when developing the PCN emission inventory. From the obtained data in the preliminary investigation, it could be seen that these investigated sources are worthy of further concerns for PCN emission. Further investigation on PCN release from thermal related process is still in process. References Kannan, K., Imagawa, T., Blankenship, A.L., et al., 1998. Isomer-specific analysis and toxic evaluation of polychlorinated naphthalenes in soil, sediment, and biota collected near the site of a former chlor-alkali plant. Environ Sci Technol 32, 2507-2514. Lerche, D., van de Plassche, E., Schwegler, A., et al., 2002. Selecting chemical substances for the UN-ECE POP protocol. Chemosphere 47, 617-630. Olivero-Verbel, J., Vivas-Reyes, R., Pacheco-Londono, et al., 2004. Discriminant analysis for activation of the aryl hydrocarbon receptor by polychlorinated naphthalenes. J Mol Struc-Theochem 678, 157-161.

Spatial assessment and source identification of heavy metals pollution in surface water using several chemometric techniques.

PubMed

Ismail, Azimah; Toriman, Mohd Ekhwan; Juahir, Hafizan; Zain, Sharifuddin Md; Habir, Nur Liyana Abdul; Retnam, Ananthy; Kamaruddin, Mohd Khairul Amri; Umar, Roslan; Azid, Azman

2016-05-15

This study presents the determination of the spatial variation and source identification of heavy metal pollution in surface water along the Straits of Malacca using several chemometric techniques. Clustering and discrimination of heavy metal compounds in surface water into two groups (northern and southern regions) are observed according to level of concentrations via the application of chemometric techniques. Principal component analysis (PCA) demonstrates that Cu and Cr dominate the source apportionment in northern region with a total variance of 57.62% and is identified with mining and shipping activities. These are the major contamination contributors in the Straits. Land-based pollution originating from vehicular emission with a total variance of 59.43% is attributed to the high level of Pb concentration in the southern region. The results revealed that one state representing each cluster (northern and southern regions) is significant as the main location for investigating heavy metal concentration in the Straits of Malacca which would save monitoring cost and time. The monitoring of spatial variation and source of heavy metals pollution at the northern and southern regions of the Straits of Malacca, Malaysia, using chemometric analysis. Copyright © 2015 Elsevier Ltd. All rights reserved.

The Identification Of The X-Ray Counterpart To PSR J2021+4026

DOE PAGES

Weisskopf, Martin C.; Romani, Roger W.; Razzano, Massimiliano; ...

2011-11-23

We report the probable identification of the X-ray counterpart to the γ-ray pulsar PSR J2021+4026 using imaging with the Chandra X-ray Observatory ACIS and timing analysis with the Fermi satellite. Given the statistical and systematic errors, the positions determined by both satellites are coincident. The X-ray source position is R.A. 20h21m30s.733, Decl. +40°26'46.04" (J2000) with an estimated uncertainty of 1."3 combined statistical and systematic error. Moreover, both the X-ray to γ-ray and the X-ray to optical flux ratios are sensible assuming a neutron star origin for the X-ray flux. The X-ray source has no cataloged infrared-to-visible counterpart and, through newmore » observations, we set upper limits to its optical emission of i' > 23.0 mag and r' > 25.2 mag. The source exhibits an X-ray spectrum with most likely both a powerlaw and a thermal component. We also report on the X-ray and visible light properties of the 43 other sources detected in our Chandra observation.« less

A medium-deep Chandra and Subaru survey of the 13-h XMM/ROSAT deep survey area

NASA Astrophysics Data System (ADS)

McHardy, I. M.; Gunn, K. F.; Newsam, A. M.; Mason, K. O.; Page, M. J.; Takata, T.; Sekiguchi, K.; Sasseen, T.; Cordova, F.; Jones, L. R.; Loaring, N.

2003-07-01

We present the results of a Chandra ACIS-I survey of a high-latitude region at 13 h +38° which was earlier observed with ROSAT and which has recently been observed by XMM-Newton for 200 ks. XMM-Newton will provide good-quality X-ray spectra for over 200 sources with fluxes around the knee of the log N/ log S, which are responsible for the bulk of the X-ray background. The main aim of the Chandra observations is to provide arcsecond, or better, positions, and hence reliable identifications, for the XMM-Newton sources. The ACIS-I observations were arranged in a mosaic of four 30-ks pointings, covering almost all of the 15-arcmin radius XMM-Newton/ROSAT field. We detect 214 Chandra sources above a Cash likelihood statistic of 25, which approximates to 5σ significance, to a limiting flux of ~1.3 × 10-15 erg cm-2 s-1 (0.5-7 keV). Optical counterparts are derived from a Subaru SuprimeCam image reaching to R~ 27. The very large majority of the Chandra sources have an optical counterpart, with the distribution peaking at 23 < R < 24, although 14 have no counterpart to R= 27. The fraction of X-ray sources with no identification brighter than R= 27 is similar to that found in deeper Chandra surveys. The majority of the identifications are with galaxies. As found in other Chandra surveys, there is a very wide range of optical magnitudes for a given X-ray flux, implying a range of emission mechanisms, and many sources have high LX/Lopt ratios, implying absorption at moderate redshift. Comparison with the earlier ROSAT survey shows that the accuracy of the ROSAT positions agrees very well with the predictions from simulations by McHardy et al. and that the large majority of the identifications were correct.

Improving volcanic sulfur dioxide cloud dispersal forecasts by progressive assimilation of satellite observations

NASA Astrophysics Data System (ADS)

Boichu, Marie; Clarisse, Lieven; Khvorostyanov, Dmitry; Clerbaux, Cathy

2014-04-01

Forecasting the dispersal of volcanic clouds during an eruption is of primary importance, especially for ensuring aviation safety. As volcanic emissions are characterized by rapid variations of emission rate and height, the (generally) high level of uncertainty in the emission parameters represents a critical issue that limits the robustness of volcanic cloud dispersal forecasts. An inverse modeling scheme, combining satellite observations of the volcanic cloud with a regional chemistry-transport model, allows reconstructing this source term at high temporal resolution. We demonstrate here how a progressive assimilation of freshly acquired satellite observations, via such an inverse modeling procedure, allows for delivering robust sulfur dioxide (SO2) cloud dispersal forecasts during the eruption. This approach provides a computationally cheap estimate of the expected location and mass loading of volcanic clouds, including the identification of SO2-rich parts.

Cosmological constraints from X-ray all sky surveys, from CODEX to eROSITA

NASA Astrophysics Data System (ADS)

Finoguenov, A.

2017-10-01

Large area cluster cosmology has long become a multiwavelength discipline. Understanding the effect of various selections is currently the main path to improving on the validity of cluster cosmological results. Many of these results are based on the large area sample derived from RASS data. We perform wavelet detection of X-ray sources and make extensive simulations of the detection of clusters in the RASS data. We assign an optical richness to each of the 25,000 detected X-ray sources in the 10,000 square degrees of SDSS BOSS area. We show that there is no obvious separation of sources on galaxy clusters and AGN, based on distribution of systems on their richness. We conclude that previous catalogs, such as MACS, REFLEX are all subject to a complex optical selection function, in addition to an X-ray selection. We provide a complete model of identification of cluster counts are galaxy clusters, which includes chance identification, effect of AGN halo occupation distribution and the thermal emission of ICM. Finally we present the cosmological results obtained using this sample.

Homogeneous spectral spanning of terahertz semiconductor lasers with radio frequency modulation.

PubMed

Wan, W J; Li, H; Zhou, T; Cao, J C

2017-03-08

Homogeneous broadband and electrically pumped semiconductor radiation sources emitting in the terahertz regime are highly desirable for various applications, including spectroscopy, chemical sensing, and gas identification. In the frequency range between 1 and 5 THz, unipolar quantum cascade lasers employing electron inter-subband transitions in multiple-quantum-well structures are the most powerful semiconductor light sources. However, these devices are normally characterized by either a narrow emission spectrum due to the narrow gain bandwidth of the inter-subband optical transitions or an inhomogeneous broad terahertz spectrum from lasers with heterogeneous stacks of active regions. Here, we report the demonstration of homogeneous spectral spanning of long-cavity terahertz semiconductor quantum cascade lasers based on a bound-to-continuum and resonant phonon design under radio frequency modulation. At a single drive current, the terahertz spectrum under radio frequency modulation continuously spans 330 GHz (~8% of the central frequency), which is the record for single plasmon waveguide terahertz lasers with a bound-to-continuum design. The homogeneous broadband terahertz sources can be used for spectroscopic applications, i.e., GaAs etalon transmission measurement and ammonia gas identification.

Homogeneous spectral spanning of terahertz semiconductor lasers with radio frequency modulation

PubMed Central

Wan, W. J.; Li, H.; Zhou, T.; Cao, J. C.

2017-01-01

Homogeneous broadband and electrically pumped semiconductor radiation sources emitting in the terahertz regime are highly desirable for various applications, including spectroscopy, chemical sensing, and gas identification. In the frequency range between 1 and 5 THz, unipolar quantum cascade lasers employing electron inter-subband transitions in multiple-quantum-well structures are the most powerful semiconductor light sources. However, these devices are normally characterized by either a narrow emission spectrum due to the narrow gain bandwidth of the inter-subband optical transitions or an inhomogeneous broad terahertz spectrum from lasers with heterogeneous stacks of active regions. Here, we report the demonstration of homogeneous spectral spanning of long-cavity terahertz semiconductor quantum cascade lasers based on a bound-to-continuum and resonant phonon design under radio frequency modulation. At a single drive current, the terahertz spectrum under radio frequency modulation continuously spans 330 GHz (~8% of the central frequency), which is the record for single plasmon waveguide terahertz lasers with a bound-to-continuum design. The homogeneous broadband terahertz sources can be used for spectroscopic applications, i.e., GaAs etalon transmission measurement and ammonia gas identification. PMID:28272492

Non-domestic phosphorus release in rivers during low-flow: Mechanisms and implications for sources identification

NASA Astrophysics Data System (ADS)

Dupas, Rémi; Tittel, Jörg; Jordan, Phil; Musolff, Andreas; Rode, Michael

2018-05-01

A common assumption in phosphorus (P) load apportionment studies is that P loads in rivers consist of flow independent point source emissions (mainly from domestic and industrial origins) and flow dependent diffuse source emissions (mainly from agricultural origin). Hence, rivers dominated by point sources will exhibit highest P concentration during low-flow, when flow dilution capacity is minimal, whereas rivers dominated by diffuse sources will exhibit highest P concentration during high-flow, when land-to-river hydrological connectivity is maximal. Here, we show that Soluble Reactive P (SRP) concentrations in three forested catchments free of point sources exhibited seasonal maxima during the summer low-flow period, i.e. a pattern expected in point source dominated areas. A load apportionment model (LAM) is used to show how point sources contribution may have been overestimated in previous studies, because of a biogeochemical process mimicking a point source signal. Almost twenty-two years (March 1995-September 2016) of monthly monitoring data of SRP, dissolved iron (Fe) and nitrate-N (NO3) were used to investigate the underlying mechanisms: SRP and Fe exhibited similar seasonal patterns and opposite to that of NO3. We hypothesise that Fe oxyhydroxide reductive dissolution might be the cause of SRP release during the summer period, and that NO3 might act as a redox buffer, controlling the seasonality of SRP release. We conclude that LAMs may overestimate the contribution of P point sources, especially during the summer low-flow period, when eutrophication risk is maximal.

Identification and characterization of fine and coarse particulate matter sources in a middle-European urban environment

NASA Astrophysics Data System (ADS)

Kertész, Zs.; Szoboszlai, Z.; Angyal, A.; Dobos, E.; Borbély-Kiss, I.

2010-06-01

In this work a source apportionment study is presented which aimed to characterize the PM 2.5 and PM 2.5-10 sources in the urban area of Debrecen, East-Hungary by using streaker samples, IBA methods and positive matrix factorization (PMF) analysis. Samples of fine (PM 2.5) and coarse (PM 2.5-10) urban particulate matter were collected with 2 h time resolution in the frame of five sampling campaigns during 2007-2009 in different seasons in the downtown of Debrecen. Elemental concentrations from Al to Pb of over 1000 samples were obtained by particle induced X-ray emission (PIXE); concentrations of black carbon (BC) were determined with a smoke stain reflectometer. On this data base source apportionment was carried out by using the PMF method. Seven factors were identified for both size fractions, including soil dust, traffic, secondary aerosol - sulphates, domestic heating, oil combustion, agriculture and an unknown factor enriched with chlorine. Seasonal and daily variation of the different factors was studied as well as their dependence on meteorological parameters. Besides determining the time patterns characteristic to the city, several emission episodes were identified including a Saharan dust intrusion on 21st-24th May, 2008.

Source identification of particulate matter in a semi-urban area of Malaysia using multivariate techniques.

PubMed

Wahid, N B A; Latif, M T; Suan, L S; Dominick, D; Sahani, M; Jaafar, S A; Mohd Tahir, N

2014-03-01

This study aims to determine the composition and sources of particulate matter with an aerodynamic diameter of 10 μm or less (PM10) in a semi-urban area. PM10 samples were collected using a high volume sampler. Heavy metals (Fe, Zn, Pb, Mn, Cu, Cd and Ni) and cations (Na(+), K(+), Ca(2+) and Mg(2+)) were detected using inductively coupled plasma mass spectrometry, while anions (SO4 (2-), NO3 (-), Cl(-) and F(-)) were analysed using Ion Chromatography. Principle component analysis and multiple linear regressions were used to identify the source apportionment of PM10. Results showed the average concentration of PM10 was 29.5 ± 5.1 μg/m(3). The heavy metals found were dominated by Fe, followed by Zn, Pb, Cu, Mn, Cd and Ni. Na(+) was the dominant cation, followed by Ca(2+), K(+) and Mg(2+), whereas SO4 (2-) was the dominant anion, followed by NO3 (-), Cl(-) and F(-). The main sources of PM10 were the Earth's crust/road dust, followed by vehicle emissions, industrial emissions/road activity, and construction/biomass burning.

Development of a methodology examining the behaviours of VOCs source apportionment with micro-meteorology analysis in an urban and industrial area.

PubMed

Xiang, Yang; Delbarre, Hervé; Sauvage, Stéphane; Léonardis, Thierry; Fourmentin, Marc; Augustin, Patrick; Locoge, Nadine

2012-03-01

During summer 2009, online measurements of 25 Volatile Organic Compounds (VOCs) from C6 to C10 as well as micro-meteorological parameters were simultaneously performed in the industrial city of Dunkerque. With the obtained data set, we developed a methodology to examine how the contributions of different source categories depend on atmospheric turbulences, and the results provided identification of emission modes. Eight factors were resolved by using Positive Matrix Factorization model and three of them were associated with mixed sources. The observed behaviours of contributions with turbulences lead to attribute some factors with sources at ground level, and some other factors with sources in the upper part of surface layer. The impact of vertical turbulence on the pollutant dispersion is also affected by the distance between sources and receptor site. Copyright © 2011 Elsevier Ltd. All rights reserved.

Pen-chant: Acoustic emissions of handwriting and drawing

NASA Astrophysics Data System (ADS)

Seniuk, Andrew G.

The sounds generated by a writing instrument ('pen-chant') provide a rich and underutilized source of information for pattern recognition. We examine the feasibility of recognition of handwritten cursive text, exclusively through an analysis of acoustic emissions. We design and implement a family of recognizers using a template matching approach, with templates and similarity measures derived variously from: smoothed amplitude signal with fixed resolution, discrete sequence of magnitudes obtained from peaks in the smoothed amplitude signal, and ordered tree obtained from a scale space signal representation. Test results are presented for recognition of isolated lowercase cursive characters and for whole words. We also present qualitative results for recognizing gestures such as circling, scratch-out, check-marks, and hatching. Our first set of results, using samples provided by the author, yield recognition rates of over 70% (alphabet) and 90% (26 words), with a confidence of +/-8%, based solely on acoustic emissions. Our second set of results uses data gathered from nine writers. These results demonstrate that acoustic emissions are a rich source of information, usable---on their own or in conjunction with image-based features---to solve pattern recognition problems. In future work, this approach can be applied to writer identification, handwriting and gesture-based computer input technology, emotion recognition, and temporal analysis of sketches.

A search for new supernova remnant shells in the Galactic plane with H.E.S.S.

NASA Astrophysics Data System (ADS)

H. E. S. S. Collaboration; Abdalla, H.; Abramowski, A.; Aharonian, F.; Ait Benkhali, F.; Akhperjanian, A. G.; Andersson, T.; Angüner, E. O.; Arakawa, M.; Arrieta, M.; Aubert, P.; Backes, M.; Balzer, A.; Barnard, M.; Becherini, Y.; Becker Tjus, J.; Berge, D.; Bernhard, S.; Bernlöhr, K.; Blackwell, R.; Böttcher, M.; Boisson, C.; Bolmont, J.; Bonnefoy, S.; Bordas, P.; Bregeon, J.; Brun, F.; Brun, P.; Bryan, M.; Büchele, M.; Bulik, T.; Capasso, M.; Carr, J.; Casanova, S.; Cerruti, M.; Chakraborty, N.; Chaves, R. C. G.; Chen, A.; Chevalier, J.; Coffaro, M.; Colafrancesco, S.; Cologna, G.; Condon, B.; Conrad, J.; Cui, Y.; Davids, I. D.; Decock, J.; Degrange, B.; Deil, C.; Devin, J.; deWilt, P.; Dirson, L.; Djannati-Ataï, A.; Domainko, W.; Donath, A.; Drury, L. O.'C.; Dutson, K.; Dyks, J.; Edwards, T.; Egberts, K.; Eger, P.; Ernenwein, J.-P.; Eschbach, S.; Farnier, C.; Fegan, S.; Fernandes, M. V.; Fiasson, A.; Fontaine, G.; Förster, A.; Funk, S.; Füßling, M.; Gabici, S.; Gajdus, M.; Gallant, Y. A.; Garrigoux, T.; Giavitto, G.; Giebels, B.; Glicenstein, J. F.; Gottschall, D.; Goyal, A.; Grondin, M.-H.; Hahn, J.; Haupt, M.; Hawkes, J.; Heinzelmann, G.; Henri, G.; Hermann, G.; Hervet, O.; Hinton, J. A.; Hofmann, W.; Hoischen, C.; Holch, T. L.; Holler, M.; Horns, D.; Ivascenko, A.; Iwasaki, H.; Jacholkowska, A.; Jamrozy, M.; Janiak, M.; Jankowsky, D.; Jankowsky, F.; Jingo, M.; Jogler, T.; Jouvin, L.; Jung-Richardt, I.; Kastendieck, M. A.; Katarzyński, K.; Katsuragawa, M.; Katz, U.; Kerszberg, D.; Khangulyan, D.; Khélifi, B.; King, J.; Klepser, S.; Klochkov, D.; Kluźniak, W.; Kolitzus, D.; Komin, Nu.; Kosack, K.; Krakau, S.; Kraus, M.; Krüger, P. P.; Laffon, H.; Lamanna, G.; Lau, J.; Lees, J.-P.; Lefaucheur, J.; Lefranc, V.; Lemière, A.; Lemoine-Goumard, M.; Lenain, J.-P.; Leser, E.; Lohse, T.; Lorentz, M.; Liu, R.; López-Coto, R.; Lypova, I.; Marandon, V.; Marcowith, A.; Mariaud, C.; Marx, R.; Maurin, G.; Maxted, N.; Mayer, M.; Meintjes, P. J.; Meyer, M.; Mitchell, A. M. W.; Moderski, R.; Mohamed, M.; Mohrmann, L.; Morå, K.; Moulin, E.; Murach, T.; Nakashima, S.; de Naurois, M.; Niederwanger, F.; Niemiec, J.; Oakes, L.; O'Brien, P.; Odaka, H.; Öttl, S.; Ohm, S.; Ostrowski, M.; Oya, I.; Padovani, M.; Panter, M.; Parsons, R. D.; Pekeur, N. W.; Pelletier, G.; Perennes, C.; Petrucci, P.-O.; Peyaud, B.; Piel, Q.; Pita, S.; Poon, H.; Prokhorov, D.; Prokoph, H.; Pühlhofer, G.; Punch, M.; Quirrenbach, A.; Raab, S.; Reimer, A.; Reimer, O.; Renaud, M.; de los Reyes, R.; Richter, S.; Rieger, F.; Romoli, C.; Rowell, G.; Rudak, B.; Rulten, C. B.; Sahakian, V.; Saito, S.; Salek, D.; Sanchez, D. A.; Santangelo, A.; Sasaki, M.; Schlickeiser, R.; Schüssler, F.; Schulz, A.; Schwanke, U.; Schwemmer, S.; Seglar-Arroyo, M.; Settimo, M.; Seyffert, A. S.; Shafi, N.; Shilon, I.; Simoni, R.; Sol, H.; Spanier, F.; Spengler, G.; Spies, F.; Stawarz, Ł.; Steenkamp, R.; Stegmann, C.; Stycz, K.; Sushch, I.; Takahashi, T.; Tavernet, J.-P.; Tavernier, T.; Taylor, A. M.; Terrier, R.; Tibaldo, L.; Tiziani, D.; Tluczykont, M.; Trichard, C.; Tsuji, N.; Tuffs, R.; Uchiyama, Y.; van der Walt, D. J.; van Eldik, C.; van Rensburg, C.; van Soelen, B.; Vasileiadis, G.; Veh, J.; Venter, C.; Viana, A.; Vincent, P.; Vink, J.; Voisin, F.; Völk, H. J.; Vuillaume, T.; Wadiasingh, Z.; Wagner, S. J.; Wagner, P.; Wagner, R. M.; White, R.; Wierzcholska, A.; Willmann, P.; Wörnlein, A.; Wouters, D.; Yang, R.; Zabalza, V.; Zaborov, D.; Zacharias, M.; Zanin, R.; Zdziarski, A. A.; Zech, A.; Zefi, F.; Ziegler, A.; Żywucka, N.; Bamba, A.; Fukui, Y.; Sano, H.; Yoshiike, S.

2018-04-01

A search for new supernova remnants (SNRs) has been conducted using TeV γ-ray data from the H.E.S.S. Galactic plane survey. As an identification criterion, shell morphologies that are characteristic for known resolved TeV SNRs have been used. Three new SNR candidates were identified in the H.E.S.S. data set with this method. Extensive multiwavelength searches for counterparts were conducted. A radio SNR candidate has been identified to be a counterpart to HESS J1534-571. The TeV source is therefore classified as a SNR. For the other two sources, HESS J1614-518 and HESS J1912+101, no identifying counterparts have been found, thus they remain SNR candidates for the time being. TeV-emitting SNRs are key objects in the context of identifying the accelerators of Galactic cosmic rays. The TeV emission of the relativistic particles in the new sources is examined in view of possible leptonic and hadronic emission scenarios, taking the current multiwavelength knowledge into account.

NMHC emissions from Asia: sources and transport

NASA Astrophysics Data System (ADS)

Shirai, T.; Blake, D. R.; Barletta, B.; Meinardi, S.; Rowland, F. S.; Chan, J. C.; Takegawa, N.; Kondo, Y.; Koike, M.; Kita, K.; Takigawa, M.; Kawakami, S.; Ogawa, T.

2002-12-01

Recent rapid industrialization and economic growth in Asia changed the industrial structure, land use, and people's lifestyle resulting in a dramatic change in the amount and composition of the gas emissions from Asia. Because emissions can be transported very rapidly once convected to the free troposphere, Asian emissions can affect both local and regional air quality and climate. To access the impact of changing emission from Asia, an airborne observation campaign PEACE (the Pacific Exploration of Asian Continental Emission) phase-A and B were conducted in January and April - May 2002, respectively, sponsored by NASDA (National Space Development Agency of Japan). The concentrations of NMHCs (nonmethanehydrocarbons) and halocarbons were obtained by whole air sampling and subsequent gas chromatography analyses in the laboratory. Quantified onboard the aircraft were CO, CO2, O3, NO, NO2, NOy, H2O, SO2, aerosols, and condensation nuclei. The experiment was conducted in the vicinity of Japan and PEACE-A and B represent the local winter and spring weather conditions. The trace gas distributions in the lower troposphere were often influenced by local pollution (i.e. from Japan, Korea) while those of the long-range transport (i.e. from Europe) were occasionally seen in the upper troposphere. This is confirmed by the airmass age estimation using the ratios of short-lived gases (i.e. C2H4) vs. more stable compounds (i.e. CO). Emissions from China were distinguished using data obtained from ground-based sampling and measurements. Transport from China was seen both in the lower troposphere and upper troposphere. Some case studies on source identification will be discussed.

PAH air pollution at a Portuguese urban area: carcinogenic risks and sources identification.

PubMed

Slezakova, K; Pires, J C M; Castro, D; Alvim-Ferraz, M C M; Delerue-Matos, C; Morais, S; Pereira, M C

2013-06-01

This study aimed to characterize air pollution and the associated carcinogenic risks of polycyclic aromatic hydrocarbon (PAHs) at an urban site, to identify possible emission sources of PAHs using several statistical methodologies, and to analyze the influence of other air pollutants and meteorological variables on PAH concentrations.The air quality and meteorological data were collected in Oporto, the second largest city of Portugal. Eighteen PAHs (the 16 PAHs considered by United States Environment Protection Agency (USEPA) as priority pollutants, dibenzo[a,l]pyrene, and benzo[j]fluoranthene) were collected daily for 24 h in air (gas phase and in particles) during 40 consecutive days in November and December 2008 by constant low-flow samplers and using polytetrafluoroethylene (PTFE) membrane filters for particulate (PM10 and PM2.5 bound) PAHs and pre-cleaned polyurethane foam plugs for gaseous compounds. The other monitored air pollutants were SO2, PM10, NO2, CO, and O3; the meteorological variables were temperature, relative humidity, wind speed, total precipitation, and solar radiation. Benzo[a]pyrene reached a mean concentration of 2.02 ng m(-3), surpassing the EU annual limit value. The target carcinogenic risks were equal than the health-based guideline level set by USEPA (10(-6)) at the studied site, with the cancer risks of eight PAHs reaching senior levels of 9.98 × 10(-7) in PM10 and 1.06 × 10(-6) in air. The applied statistical methods, correlation matrix, cluster analysis, and principal component analysis, were in agreement in the grouping of the PAHs. The groups were formed according to their chemical structure (number of rings), phase distribution, and emission sources. PAH diagnostic ratios were also calculated to evaluate the main emission sources. Diesel vehicular emissions were the major source of PAHs at the studied site. Besides that source, emissions from residential heating and oil refinery were identified to contribute to PAH levels at the respective area. Additionally, principal component regression indicated that SO2, NO2, PM10, CO, and solar radiation had positive correlation with PAHs concentrations, while O3, temperature, relative humidity, and wind speed were negatively correlated.

GHG emissions quantification at high spatial and temporal resolution at urban scale: the case of the town of Sassari (NW Sardinia - Italy)

NASA Astrophysics Data System (ADS)

Sanna, Laura; Ferrara, Roberto; Zara, Pierpaolo; Duce, Pierpaolo

2014-05-01

The European Union has set as priorities the fight against climate change related to greenhouse gas releases. The largest source of these emissions comes from human activities in urban areas that account for more than 70% of the world's emissions and several local governments intend to support the European strategic policies in understanding which crucial sectors drive GHG emissions in their city. Planning for mitigation actions at the community scale starts with the compilation of a GHG inventories that, among a wide range of measurement tools, provide information on the current status of GHG emissions across a specific jurisdiction. In the framework of a regional project for quantitative estimate of the net exchange of CO2 (emissions and sinks) at the municipal level in Sardinia, the town of Sassari represents a pilot site where a spatial and temporal high resolution GHG emissions inventory is built in line with European and international standard protocols to establish a baseline for tracking emission trends. The specific purpose of this accurate accounting is to obtain an appropriate allocation of CO2 and other GHG emissions at the fine building and hourly scale. The aim is to test the direct measurements needed to enable the construction of future scenarios of these emissions and for assessing possible strategies to reduce their impact. The key element of the methodologies used to construct this GHG emissions inventory is the Global Protocol for Community-Scale Greenhouse Gas Emissions (GPC) (March 2012) that identifies four main types of emission sources: (i) Stationary Units, (ii) Mobile Units, (iii) Waste, and (iv) Industrial Process and Product Use Emissions. The development of the GHG emissions account in Sassari consists in the collection of a range of alternative data sources (primary data, IPCC emission factors, national and local statistic, etc.) selected on the base on relevance and completeness criteria performed for 2010, as baseline year, using top-down, bottom-up or mixed approaches. GPC protocol also defines three standard scopes for downscaling emissions from the national to the community level, that allow to handle the attribution of releases that occur outside the community boundary as a result of activity or consumption within it. The procedures for data processing have simple and concise structure, applicable in different communities that led to the possibility to compare the results with other national contexts. An appropriate GHG emissions allocation over detailed spatial and temporal scales has been achieved on the basis of specific indicators (population, industrial employees, amount of product, etc.) and of geo-location and size of all buildings, using appropriate models, that enable to properly georeference them respect to their uses. The main advantage of neighborhood-level quantification consists in the identification of the main productive sources and emissive activities within the urban boundaries that mostly contribute to the current GHG emissions and then focus the efforts on possible mitigation.

Source apportionment of airborne particulates through receptor modeling: Indian scenario

NASA Astrophysics Data System (ADS)

Banerjee, Tirthankar; Murari, Vishnu; Kumar, Manish; Raju, M. P.

2015-10-01

Airborne particulate chemistry mostly governed by associated sources and apportionment of specific sources is extremely essential to delineate explicit control strategies. The present submission initially deals with the publications (1980s-2010s) of Indian origin which report regional heterogeneities of particulate concentrations with reference to associated species. Such meta-analyses clearly indicate the presence of reservoir of both primary and secondary aerosols in different geographical regions. Further, identification of specific signatory molecules for individual source category was also evaluated in terms of their scientific merit and repeatability. Source signatures mostly resemble international profile while, in selected cases lack appropriateness. In India, source apportionment (SA) of airborne particulates was initiated way back in 1985 through factor analysis, however, principal component analysis (PCA) shares a major proportion of applications (34%) followed by enrichment factor (EF, 27%), chemical mass balance (CMB, 15%) and positive matrix factorization (PMF, 9%). Mainstream SA analyses identify earth crust and road dust resuspensions (traced by Al, Ca, Fe, Na and Mg) as a principal source (6-73%) followed by vehicular emissions (traced by Fe, Cu, Pb, Cr, Ni, Mn, Ba and Zn; 5-65%), industrial emissions (traced by Co, Cr, Zn, V, Ni, Mn, Cd; 0-60%), fuel combustion (traced by K, NH4+, SO4-, As, Te, S, Mn; 4-42%), marine aerosols (traced by Na, Mg, K; 0-15%) and biomass/refuse burning (traced by Cd, V, K, Cr, As, TC, Na, K, NH4+, NO3-, OC; 1-42%). In most of the cases, temporal variations of individual source contribution for a specific geographic region exhibit radical heterogeneity possibly due to unscientific orientation of individual tracers for specific source and well exaggerated by methodological weakness, inappropriate sample size, implications of secondary aerosols and inadequate emission inventories. Conclusively, a number of challenging issues and specific recommendations have been included which need to be considered for a scientific apportionment of particulate sources in different geographical regions of India.

Chemical characterization of fine organic aerosol for source apportionment at Monterrey, Mexico

NASA Astrophysics Data System (ADS)

Mancilla, Y.; Mendoza, A.; Fraser, M. P.; Herckes, P.

2015-07-01

Primary emissions from anthropogenic and biogenic sources as well as secondary formation are responsible for the pollution levels of ambient air in major urban areas. These sources release fine particles into the air that negatively impact human health and the environment. Organic molecular markers, which are compounds that are unique to specific PM2.5 sources, can be utilized to identify the major emission sources in urban areas. In this study, 43 representative PM2.5 samples, for both daytime and nighttime periods, were built from individual samples collected in an urban site of the Monterrey Metropolitan Area (MMA) during the spring and fall of 2011 and 2012. The samples were analyzed for organic carbon, elemental carbon, and organic molecular markers. Several diagnostic tools were employed for the preliminary identification of emission sources. Organic compounds for eight compound classes were quantified. The n-alkanoic acids were the most abundant, followed by n-alkanes, wood smoke markers, and levoglucosan/alkenoic acids. Polycyclic aromatic hydrocarbons (PAHs) and hopanes were less abundant. The carbon preference index (0.7-2.6) for n-alkanes indicate a major contribution of anthropogenic and mixed sources during the fall and the spring, respectively. Hopanes levels confirmed the contribution from gasoline and diesel engines. In addition, the contribution of gasoline and diesel vehicle exhaust was confirmed and identified by the PAH concentrations in PM2.5. Diagnostic ratios of PAH showed emissions from burning coal, wood, biomass, and other fossil fuels. The total PAH and elemental carbon (EC) were correlated (r2 = 0.39-0.70) across the monitoring periods, reinforcing that motor vehicles are the major contributors of PAH. Cholesterol levels remained constant during the spring and fall, showing evidence of the contribution of meat cooking operations, while the isolated concentrations of levoglucosan suggested occasional biomass burning events. Finally, source attribution results obtained using the CMB model indicate that emissions from motor vehicle exhausts are the most important, accounting for the 64 % of the PM2.5. The vegetative detritus and biomass burning had the smallest contribution (2.2 % of the PM2.5). To our knowledge, this is the second study to explore the broad chemical characterization of fine organic aerosol in Mexico and the first for the MMA.

Retrieval columns of SO2 in industrial chimneys using DOAS passive in traverse

NASA Astrophysics Data System (ADS)

Galicia Mejía, Rubén; de la Rosa Vázquez, José Manuel; Sosa Iglesias, Gustavo

2011-10-01

The optical Differential Optical Absorption Spectroscopy (DOAS) is a technique to measure pollutant emissions like SO2, from point sources and total fluxes in the atmosphere. Passive DOAS systems use sunlight like source. Measurements with such systems can be made in situ and in real time. The goal of this work is to report the implementation of hardware and software of a portable system to evaluate the pollutants emitted in the atmosphere by industrial chimneys. We show SO2 measurements obtained around PEMEX refinerys in Tula Hidalgo that enables the identification of their pollution degree with the knowledge of speed wind.

HONO and Inorganic Fine Particle Composition in Typical Monsoon Region with Intensive Anthropogenic Emission: In-situ Observations and Source Identification.

NASA Astrophysics Data System (ADS)

Xie, Y.; Nie, W.; Ding, A.; Huang, X.

2015-12-01

Yangtze River Delta (YRD) is one of the most typical monsoon area with probably the most largest population intensity in the world. With sharply economic development and the large anthropogenic emissions, fine particle pollution have been one of the major air quality problem and may further have impact on the climate system. Though a lot of control policy (sulfur emission have been decreasing from 2007) have been conducted in the region, studies showed the sulfate in fine particles still take major fraction as the nitrate from nitrogen oxides increased significantly. In this study, the role of inorganic chemical compositions in fine particles was investigated with two years in-situ observation. Sulfate and Nitrate contribute to fine particle mass equally in general, but sulfate contributes more during summer and nitrate played more important role in winter. Using lagrangian dispersion backward modeling and source contribution clustering method, the impact of airmass coming from different source region (industrial, dust, biogenic emissions, etc) on fine particle inorganic compositions were discussed. Furthermore, we found two unique cases showing in-situ implications for sulfate formation by nitrogen dioxide oxidation mechanisms. It was showed that the mixing of anthropogenic pollutants with long-range transported mineral dust and biomass burning plume would enhance the sulfate formation by different chemistry mechanisms. This study focus on the complex aspects of fine particle formation in airmasses from different source regions: . It highlights the effect of NOx in enhancing the atmospheric oxidization capacity and indicates a potentially very important impact of increasing NOx on air pollution formation and regional climate change in East Asia.

Emissions of perfluorinated alkylated substances (PFAS) from point sources--identification of relevant branches.

PubMed

Clara, M; Scheffknecht, C; Scharf, S; Weiss, S; Gans, O

2008-01-01

Effluents of wastewater treatment plants are relevant point sources for the emission of hazardous xenobiotic substances to the aquatic environment. One group of substances, which recently entered scientific and political discussions, is the group of the perfluorinated alkylated substances (PFAS). The most studied compounds from this group are perfluorooctanoic acid (PFOA) and perfluorooctane sulphonate (PFOS), which are the most important degradation products of PFAS. These two substances are known to be persistent, bioaccumulative and toxic (PBT). In the present study, eleven PFAS were investigated in effluents of municipal wastewater treatment plants (WWTP) and in industrial wastewaters. PFOS and PFOA proved to be the dominant compounds in all sampled wastewaters. Concentrations of up to 340 ng/L of PFOS and up to 220 ng/L of PFOA were observed. Besides these two compounds, perfluorohexanoic acid (PFHxA) was also present in nearly all effluents and maximum concentrations of up to 280 ng/L were measured. Only N-ethylperfluorooctane sulphonamide (N-EtPFOSA) and its degradation/metabolisation product perfluorooctane sulphonamide (PFOSA) were either detected below the limit of quantification or were not even detected at all. Beside the effluents of the municipal WWTPs, nine industrial wastewaters from six different industrial branches were also investigated. Significantly, the highest emissions or PFOS were observed from metal industry whereas paper industry showed the highest PFOA emission. Several PFAS, especially perfluorononanoic acid (PFNA), perfluorodecanoic acid (PFDA), perfluorododecanoic acid (PFDoA) and PFOS are predominantly emitted from industrial sources, with concentrations being a factor of 10 higher than those observed in the municipal WWTP effluents. Perfluorodecane sulphonate (PFDS), N-Et-PFOSA and PFOSA were not detected in any of the sampled industrial point sources. (c) IWA Publishing 2008.

X-Ray Measurements Of A Thermo Scientific P385 DD Neutron Generator

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

Wharton, C. J.; Seabury, E. H.; Chichester, D. L.

2011-06-01

Idaho National Laboratory is experimenting with electrical neutron generators, as potential replacements for californium-252 radioisotopic neutron sources in its PINS prompt gamma-ray neutron activation analysis (PGNAA) system for the identification of military chemical warfare agents and explosives. In addition to neutron output, we have recently measured the x-ray output of the Thermo Scientific P385 deuterium-deuterium neutron generator. X rays are a normal byproduct from neutron generators, but depending on their intensity and energy, x rays can interfere with gamma rays from the object under test, increase gamma-spectrometer dead time, and reduce PGNAA system throughput. The P385 x-ray energy spectrum wasmore » measured with a high-purity germanium (HPGe) detector, and a broad peak is evident at about 70 keV. To identify the source of the x rays within the neutron generator assembly, it was scanned by collimated scintillation detectors along its long axis. At the strongest x-ray emission points, the generator also was rotated 60 deg. between measurements. The scans show the primary source of x-ray emission from the P385 neutron generator is an area 60 mm from the neutron production target, in the vicinity of the ion source. Rotation of the neutron generator did not significantly alter the x-ray count rate, and its x-ray emission appears to be axially symmetric. A thin lead shield, 3.2 mm (1/8 inch) thick, reduced the 70-keV generator x rays to negligible levels.« less

X-Ray Measurements Of A Thermo Scientific P385 DD Neutron Generator

NASA Astrophysics Data System (ADS)

Wharton, C. J.; Seabury, E. H.; Chichester, D. L.; Caffrey, A. J.; Simpson, J.; Lemchak, M.

2011-06-01

Idaho National Laboratory is experimenting with electrical neutron generators, as potential replacements for californium-252 radioisotopic neutron sources in its PINS prompt gamma-ray neutron activation analysis (PGNAA) system for the identification of military chemical warfare agents and explosives. In addition to neutron output, we have recently measured the x-ray output of the Thermo Scientific P385 deuterium-deuterium neutron generator. X rays are a normal byproduct from neutron generators, but depending on their intensity and energy, x rays can interfere with gamma rays from the object under test, increase gamma-spectrometer dead time, and reduce PGNAA system throughput. The P385 x-ray energy spectrum was measured with a high-purity germanium (HPGe) detector, and a broad peak is evident at about 70 keV. To identify the source of the x rays within the neutron generator assembly, it was scanned by collimated scintillation detectors along its long axis. At the strongest x-ray emission points, the generator also was rotated 60° between measurements. The scans show the primary source of x-ray emission from the P385 neutron generator is an area 60 mm from the neutron production target, in the vicinity of the ion source. Rotation of the neutron generator did not significantly alter the x-ray count rate, and its x-ray emission appears to be axially symmetric. A thin lead shield, 3.2 mm (1/8 inch) thick, reduced the 70-keV generator x rays to negligible levels.

LOCALIZING INTEGRAL SOURCES WITH CHANDRA: X-RAY AND MULTI-WAVELENGTH IDENTIFICATIONS AND ENERGY SPECTRA

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

Tomsick, John A.; Bodaghee, Arash; Chaty, Sylvain

2012-08-01

We report on Chandra observations of 18 hard X-ray (>20 keV) sources discovered with the INTEGRAL satellite near the Galactic plane. For 14 of the INTEGRAL sources, we have uncovered one or two potential Chandra counterparts per source. These provide soft X-ray (0.3-10 keV) spectra and subarcsecond localizations, which we use to identify counterparts at other wavelengths, providing information about the nature of each source. Despite the fact that all of the sources are within 5 Degree-Sign of the plane, four of the IGR sources are active galactic nuclei (AGNs; IGR J01545+6437, IGR J15391-5307, IGR J15415-5029, and IGR J21565+5948) andmore » four others are likely AGNs (IGR J03103+5706, IGR J09189-4418, IGR J16413-4046, and IGR J16560-4958) based on each of them having a strong IR excess and/or extended optical or near-IR emission. We compare the X-ray and near-IR fluxes of this group of sources to those of AGNs selected by their 2-10 keV emission in previous studies and find that these IGR AGNs are in the range of typical values. There is evidence in favor of four of the sources being Galactic (IGR J12489-6243, IGR J15293-5609, IGR J16173-5023, and IGR J16206-5253), but only IGR J15293-5609 is confirmed as a Galactic source as it has a unique Chandra counterpart and a parallax measurement from previous optical observations that puts its distance at 1.56 {+-} 0.12 kpc. The 0.3-10 keV luminosity for this source is (1.4{sup +1.0}{sub -0.4}) Multiplication-Sign 10{sup 32} erg s{sup -1}, and its optical/IR spectral energy distribution is well described by a blackbody with a temperature of 4200-7000 K and a radius of 12.0-16.4 R{sub Sun }. These values suggest that IGR J15293-5609 is a symbiotic binary with an early K-type giant and a white dwarf accretor. We also obtained likely Chandra identifications for IGR J13402-6428 and IGR J15368-5102, but follow-up observations are required to constrain their source types.« less

Environmental accounting for Arctic shipping - a framework building on ship tracking data from satellites.

PubMed

Mjelde, A; Martinsen, K; Eide, M; Endresen, Ø

2014-10-15

Arctic shipping is on the rise, leading to increased concern over the potential environmental impacts. To better understand the magnitude of influence to the Arctic environment, detailed modelling of emissions and environmental risks are essential. This paper describes a framework for environmental accounting. A cornerstone in the framework is the use of Automatic Identification System (AIS) ship tracking data from satellites. When merged with ship registers and other data sources, it enables unprecedented accuracy in modelling and geographical allocation of emissions and discharges. This paper presents results using two of the models in the framework; emissions of black carbon (BC) in the Arctic, which is of particular concern for climate change, and; bunker fuels and wet bulk carriage in the Arctic, of particular concern for oil spill to the environment. Using the framework, a detailed footprint from Arctic shipping with regards to operational emissions and potential discharges is established. Copyright © 2014 Elsevier Ltd. All rights reserved.

Identifying potential exposure reduction priorities using regional rankings based on emissions of known and suspected carcinogens to outdoor air in Canada.

PubMed

Setton, Eleanor M; Veerman, Basil; Erickson, Anders; Deschenes, Steeve; Cheasley, Roz; Poplawski, Karla; Demers, Paul A; Keller, C Peter

2015-08-22

Emissions inventories aid in understanding the sources of hazardous air pollutants and how these vary regionally, supporting targeted reduction actions. Integrating information on the relative toxicity of emitted pollutants with respect to cancer in humans helps to further refine reduction actions or recommendations, but few national programs exist in North America that use emissions estimates in this way. The CAREX Canada Emissions Mapping Project provides key regional indicators of emissions (total annual and total annual toxic equivalent, circa 2011) of 21 selected known and suspected carcinogens. The indicators were calculated from industrial emissions reported to the National Pollutant Release Inventory (NPRI) and estimates of emissions from transportation (airports, trains, and car and truck traffic) and residential heating (oil, gas and wood), in conjunction with human toxicity potential factors. We also include substance-specific annual emissions in toxic equivalent kilograms and annual emissions in kilograms, to allow for ranking substances within any region. For provinces and territories in Canada, the indicators suggest the top five substances contributing to the total toxic equivalent emissions in any region could be prioritized for further investigation. Residents of Quebec and New Brunswick may be more at risk of exposure to industrial emissions than those in other regions, suggesting that a more detailed study of exposure to industrial emissions in these provinces is warranted. Residential wood smoke may be an important emission to control, particularly in the north and eastern regions of Canada. Residential oil and gas heating, along with rail emissions contribute little to regional emissions and therefore may not be an immediate regional priority. The developed indicators support the identification of pollutants and sources for additional investigation when planning exposure reduction actions among Canadian provinces and territories, but have important limitations similar to other emissions inventory-based tools. Additional research is required to evaluate how the Emissions Mapping Project is used by different groups and organizations with respect to informing actions aimed at reducing Canadians' potential exposure to harmful air pollutants.

OSCAR: A new modular device for the identification and correlation of low energy particles

NASA Astrophysics Data System (ADS)

Dell'Aquila, D.; Lombardo, I.; Verde, G.; Vigilante, M.; Ausanio, G.; Ordine, A.; Miranda, M.; De Luca, M.; Alba, R.; Augey, L.; Barlini, S.; Bonnet, E.; Borderie, B.; Bougault, R.; Bruno, M.; Camaiani, A.; Casini, G.; Chbihi, A.; Cicerchia, M.; Cinausero, M.; Fabris, D.; Faible, Q.; Francalanza, L.; Frankland, J. D.; Grassi, L.; Gramegna, F.; Gruyer, D.; Kordyasz, A. J.; Kozik, T.; LaTorre, R.; Le Neindre, N.; Lopez, O.; Marchi, T.; Morelli, L.; Ottanelli, P.; Parlog, M.; Pastore, G.; Pasquali, G.; Piantelli, S.; Santonocito, D.; Stefanini, A. A.; Tortone, G.; Valdrè, S.; Vient, E.

2018-01-01

A new modular and high versatility hodoscope, OSCAR, has been developed and characterized. The aim of this hodoscope is to work as an ancillary detector of present large acceptance heavy ion detectors in specific angular regions where low thresholds and high granularities are needed. We discuss the capabilities of OSCAR in the ΔE-E identification of very low energy light particles, providing a precise map of the thickness uniformity of the ΔE (SSSSD, 20 μm) stage and showing how the thickness gradient affects the identification of particles. Energy spectra of light identified particles produced in Ca+Ca collisions at 35AMeV are used to investigate isospin transport phenomena involving the emission of low energy particles from the quasi-target (QT) source in semi-peripheral nuclear collisions. The possibility to explore particle-particle correlations are also discussed.

Tuning extreme ultraviolet emission for optimum coupling with multilayer mirrors for future lithography through control of ionic charge states

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

Ohashi, Hayato, E-mail: ohashi@cc.utsunomiya-u.ac.jp; Higashiguchi, Takeshi, E-mail: higashi@cc.utsunomiya-u.ac.jp; Suzuki, Yuhei

2014-01-21

We report on the identification of the optimum plasma conditions for a laser-produced plasma source for efficient coupling with multilayer mirrors at 6.x nm for beyond extreme ultraviolet lithography. A small shift to lower energies of the peak emission for Nd:YAG laser-produced gadolinium plasmas was observed with increasing laser power density. Charge-defined emission spectra were observed in electron beam ion trap (EBIT) studies and the charge states responsible identified by use of the flexible atomic code (FAC). The EBIT spectra displayed a larger systematic shift of the peak wavelength of intense emission at 6.x nm to longer wavelengths with increasingmore » ionic charge. This combination of spectra enabled the key ion stage to be confirmed as Gd{sup 18+}, over a range of laser power densities, with contributions from Gd{sup 17+} and Gd{sup 19+} responsible for the slight shift to longer wavelengths in the laser-plasma spectra. The FAC calculation also identified the origin of observed out-of-band emission and the charge states responsible.« less

The role of the continuous wavelet transform in mineral identification using hyperspectral imaging in the long-wave infrared by using SVM classifier

NASA Astrophysics Data System (ADS)

Sojasi, Saeed; Yousefi, Bardia; Liaigre, Kévin; Ibarra-Castanedo, Clemente; Beaudoin, Georges; Maldague, Xavier P. V.; Huot, François; Chamberland, Martin

2017-05-01

Hyperspectral imaging (HSI) in the long-wave infrared spectrum (LWIR) provides spectral and spatial information concerning the emissivity of the surface of materials, which can be used for mineral identification. For this, an endmember, which is the purest form of a mineral, is used as reference. All pure minerals have specific spectral profiles in the electromagnetic wavelength, which can be thought of as the mineral's fingerprint. The main goal of this paper is the identification of minerals by LWIR hyperspectral imaging using a machine learning scheme. The information of hyperspectral imaging has been recorded from the energy emitted from the mineral's surface. Solar energy is the source of energy in remote sensing, while a heating element is the energy source employed in laboratory experiments. Our work contains three main steps where the first step involves obtaining the spectral signatures of pure (single) minerals with a hyperspectral camera, in the long-wave infrared (7.7 to 11.8 μm), which measures the emitted radiance from the minerals' surface. The second step concerns feature extraction by applying the continuous wavelet transform (CWT) and finally we use support vector machine classifier with radial basis functions (SVM-RBF) for classification/identification of minerals. The overall accuracy of classification in our work is 90.23+/- 2.66%. In conclusion, based on CWT's ability to capture the information of signals can be used as a good marker for classification and identification the minerals substance.

Development of methodologies for identification and quantification of hazardous air pollutants from turbine engine emissions.

PubMed

Anneken, David; Striebich, Richard; DeWitt, Matthew J; Klingshirn, Christopher; Corporan, Edwin

2015-03-01

Aircraft turbine engines are a significant source of particulate matter (PM) and gaseous emissions in the vicinity of airports and military installations. Hazardous air pollutants (HAPs) (e.g., formaldehyde, benzene, naphthalene and other compounds) associated with aircraft emissions are an environmental concern both in flight and at ground level. Therefore, effective sampling, identification, and accurate measurement of these trace species are important to assess their environmental impact. This effort evaluates two established ambient air sampling and analysis methods, U.S. Environmental Protection Agency (EPA) Method TO-11A and National Institute for Occupational Safety and Health (NIOSH) Method 1501, for potential use to quantify HAPs from aircraft turbine engines. The techniques were used to perform analysis of the exhaust from a T63 turboshaft engine, and were examined using certified gas standards transferred through the heated sampling systems used for engine exhaust gaseous emissions measurements. Test results show that the EPA Method TO-11A (for aldehydes) and NIOSH Method 1501 (for semivolatile hydrocarbons) were effective techniques for the sampling and analysis of most HAPs of interest. Both methods showed reasonable extraction efficiencies of HAP species from the sorbent tubes, with the exception of acrolein, styrene, and phenol, which were not well quantified. Formaldehyde measurements using dinitrophenylhydrazine (DNPH) tubes (EPA method TO-11A) were accurate for gas-phase standards, and compared favorably to measurements using gas-phase Fourier-transform infrared (FTIR) spectroscopy. In general, these two standard methodologies proved to be suitable techniques for field measurement of turbine engine HAPs within a reasonable (5-10 minutes) sampling period. Details of the tests, the analysis methods, calibration procedures, and results from the gas standards and T63 engine tested using a conventional JP-8 jet fuel are provided. HAPs from aviation-related sources are important because of their adverse health and environmental impacts in and around airports and flight lines. Simpler, more convenient techniques to measure the important HAPs, especially aldehydes and volatile organic HAPs, are needed to provide information about their occurrence and assist in the development of engines that emit fewer harmful emissions.

Untargeted Identification of Wood Type-Specific Markers in Particulate Matter from Wood Combustion.

PubMed

Weggler, Benedikt A; Ly-Verdu, Saray; Jennerwein, Maximilian; Sippula, Olli; Reda, Ahmed A; Orasche, Jürgen; Gröger, Thomas; Jokiniemi, Jorma; Zimmermann, Ralf

2016-09-20

Residential wood combustion emissions are one of the major global sources of particulate and gaseous organic pollutants. However, the detailed chemical compositions of these emissions are poorly characterized due to their highly complex molecular compositions, nonideal combustion conditions, and sample preparation steps. In this study, the particulate organic emissions from a masonry heater using three types of wood logs, namely, beech, birch, and spruce, were chemically characterized using thermal desorption in situ derivatization coupled to a GCxGC-ToF/MS system. Untargeted data analyses were performed using the comprehensive measurements. Univariate and multivariate chemometric tools, such as analysis of variance (ANOVA), principal component analysis (PCA), and ANOVA simultaneous component analysis (ASCA), were used to reduce the data to highly significant and wood type-specific features. This study reveals substances not previously considered in the literature as meaningful markers for differentiation among wood types.

The North American Energy System: Chapter 3 of SOCCR-2

NASA Astrophysics Data System (ADS)

Gurney, K. R.; Marcotullio, P. J.; McGlynn, E.; Bruhwiler, L.; Davis, K. J.; Davis, S. J.; Engel-Cox, J.; Field, J.; Gately, C.; Kammen, D. M.; McMahon, J.; Morrow, W.; Torrie, R.

2017-12-01

North America (Canada, Mexico and the United States), has a large and complex energy system, which in this case includes the extraction and conversion of primary energy sources and their storage, transmission, distribution and ultimate end use in the building, transportation and industrial sectors. The presentation assesses the contribution of this energy system to the carbon cycle. The assessment includes the identification of CO2 emissions from fossil fuel use in the different end use, changes over the past 10 years (since the last SOCCR) and the drivers of change. The assessment focuses on our understanding of the energy trends and system feedback dynamics, key drivers of change as a basis for carbon management. The energy systems' carbon emissions from the North American system are placed in global context and a review of scenarios into the future emissions levels, which demonstrate the requirements for de-carbonization in the medium and longer term.

Modelling of point and diffuse pollution: application of the Moneris model in the Ipojuca river basin, Pernambuco State, Brazil.

PubMed

de Lima Barros, Alessandra Maciel; do Carmo Sobral, Maria; Gunkel, Günter

2013-01-01

Emissions of pollutants and nutrients are causing several problems in aquatic ecosystems, and in general an excess of nutrients, specifically nitrogen and phosphorus, is responsible for the eutrophication process in water bodies. In most developed countries, more attention is given to diffuse pollution because problems with point pollution have already been solved. In many non-developed countries basic data for point and diffuse pollution are not available. The focus of the presented studies is to quantify nutrient emissions from point and diffuse sources in the Ipojuca river basin, Pernambuco State, Brazil, using the Moneris model (Modelling Nutrient Emissions in River Systems). This model has been developed in Germany and has already been implemented in more than 600 river basins. The model is mainly based on river flow, water quality and geographical information system data. According to the Moneris model results, untreated domestic sewage is the major source of nutrients in the Ipojuca river basin. The Moneris model has shown itself to be a useful tool that allows the identification and quantification of point and diffuse nutrient sources, thus enabling the adoption of measures to reduce them. The Moneris model, conducted for the first time in a tropical river basin with intermittent flow, can be used as a reference for implementation in other watersheds.

Isolation of methanotrophic bacteria from a london landfill: a preliminary study using molecular and stable isotopic techniques.

NASA Astrophysics Data System (ADS)

Sriskantharajah, S.; Cutting, S.; Lowry, D.; Grassineau, N.; Nisbet, E.

2003-04-01

Methane emissions from landfills are an important source of European greenhouse emissions, and could be reduced by a biological management program that used methanotrophs in landfill cover soils. Topsoil samples taken from a London Landfill were incubated on Nitrate Mineral Salts medium in the presence of methane. The resulting colonies were probed for methanotrophic DNA using PCR amplification. DNA from methanotroph positive colonies was cloned and sequenced for identification. Isolates belonging to the genera Methylocaldum, Methylomonas and Methylosinus were detected. Phylogenetic analysis suggests the presence of possible new species. In addition dried samples of the isolates were analysed for their stable carbon isotope (δ 13C) composition. The results were δ 13C values of -27 per mil and -25 per mil for Methylomonas isolates, -35 per mil and -44 per mil for Methylosinus isolates, -58 per mil and -60 per mil for some of the Methylocaldum isolates and -35 per mil and -45 per mil for the others. This isotopic variation is reflected in a phylogenetic tree of the isolates. The differences shown in the δ 13C analysis could be due to differing biochemical properties, and if the technique is further developed, it may be used for rapid identification of bacteria useful in landfill management for reducing methane emissions. The results suggest that useful reductions in methane emissions could be achieved by a careful design of landfill cover to culture methanotrophs.

A catalogue of chromospherically active binary stars (third edition)

NASA Astrophysics Data System (ADS)

Eker, Z.; Ak, N. Filiz; Bilir, S.; Doǧru, D.; Tüysüz, M.; Soydugan, E.; Bakış, H.; Uǧraş, B.; Soydugan, F.; Erdem, A.; Demircan, O.

2008-10-01

The catalogue of chromospherically active binaries (CABs) has been revised and updated. With 203 new identifications, the number of CAB stars is increased to 409. The catalogue is available in electronic format where each system has a number of lines (suborders) with a unique order number. The columns contain data of limited numbers of selected cross references, comments to explain peculiarities and the position of the binarity in case it belongs to a multiple system, classical identifications (RS Canum Venaticorum, BY Draconis), brightness and colours, photometric and spectroscopic data, a description of emission features (CaII H and K, Hα, ultraviolet, infrared), X-ray luminosity, radio flux, physical quantities and orbital information, where each basic entry is referenced so users can go to the original sources.

VizieR Online Data Catalog: Chromospherically Active Binaries. Third version (Eker+, 2008)

NASA Astrophysics Data System (ADS)

Eker, Z.; Filiz-Ak, N.; Bilir, S.; Dogru, D.; Tuysuz, M.; Soydugan, E.; Bakis, H.; Ugras, B.; Soydugan, F.; Erdem, A.; Demircan, O.

2008-06-01

Chromospherically Active Binaries (CAB) catalogue have been revised and updated. With 203 new identifications, the number of CAB stars is increased to 409. Catalogue is available in electronic format where each system has various number of lines (sub-orders) with a unique order number. Columns contain data of limited number of selected cross references, comments to explain peculiarities and position of the binarity in case it belongs to a multiple system, classical identifications (RS CVn, BY Dra), brightness and colours, photometric and spectroscopic data, description of emission features (Ca II H&K, Hα, UV, IR), X-Ray luminosity, radio flux, physical quantities and orbital information, where each basic entry are referenced so users can go original sources. (10 data files).

Source apportionment of ambient non-methane hydrocarbons in Hong Kong: application of a principal component analysis/absolute principal component scores (PCA/APCS) receptor model.

PubMed

Guo, H; Wang, T; Louie, P K K

2004-06-01

Receptor-oriented source apportionment models are often used to identify sources of ambient air pollutants and to estimate source contributions to air pollutant concentrations. In this study, a PCA/APCS model was applied to the data on non-methane hydrocarbons (NMHCs) measured from January to December 2001 at two sampling sites: Tsuen Wan (TW) and Central & Western (CW) Toxic Air Pollutants Monitoring Stations in Hong Kong. This multivariate method enables the identification of major air pollution sources along with the quantitative apportionment of each source to pollutant species. The PCA analysis identified four major pollution sources at TW site and five major sources at CW site. The extracted pollution sources included vehicular internal engine combustion with unburned fuel emissions, use of solvent particularly paints, liquefied petroleum gas (LPG) or natural gas leakage, and industrial, commercial and domestic sources such as solvents, decoration, fuel combustion, chemical factories and power plants. The results of APCS receptor model indicated that 39% and 48% of the total NMHCs mass concentrations measured at CW and TW were originated from vehicle emissions, respectively. 32% and 36.4% of the total NMHCs were emitted from the use of solvent and 11% and 19.4% were apportioned to the LPG or natural gas leakage, respectively. 5.2% and 9% of the total NMHCs mass concentrations were attributed to other industrial, commercial and domestic sources, respectively. It was also found that vehicle emissions and LPG or natural gas leakage were the main sources of C(3)-C(5) alkanes and C(3)-C(5) alkenes while aromatics were predominantly released from paints. Comparison of source contributions to ambient NMHCs at the two sites indicated that the contribution of LPG or natural gas at CW site was almost twice that at TW site. High correlation coefficients (R(2) > 0.8) between the measured and predicted values suggested that the PCA/APCS model was applicable for estimation of sources of NMHCs in ambient air.

Identification of nitrate sources in groundwater using a stable isotope and 3DEEM in a landfill in Northeast China.

PubMed

Ma, Zhifei; Yang, Yu; Lian, Xinying; Jiang, Yonghai; Xi, Beidou; Peng, Xing; Yan, Kun

2016-09-01

The groundwater was sampled in a typical landfill area of the Northeast China. Coupled stable isotope and three dimensional excitation-emission matrix (3DEEM) were applied to dentify diffused NO3(-) inputs in the groundwater in this area. The results indicated that combined with the feature of groundwater hydrochemistry and three-dimensional fluorescence technology can effectively identify the nitrate pollution sources. The nitrate was derived from manure and sewage by δ(15)N and δ(18)O-NO3(-) values of groundwater in the different periods. The excitation-emission matrix fluorescence spectroscopy was further evidence of groundwater DOM mainly which comes from the landfill. The protein-like was very significant at the sampling points near the landfill (SPNL), but only fulvic acid-like appeared at downstream of the landfill groundwater sampling points (DLGSP) in the study area. Partial denitrification processes helped to attenuate nitrate concentration in anaerobic environment. Copyright © 2016 Elsevier B.V. All rights reserved.

40 CFR 62.10130 - Identification of plan-negative declaration.

Code of Federal Regulations, 2011 CFR

2011-07-01

... POLLUTANTS South Carolina Fluoride Emissions from Phosphate Fertilizer Plants § 62.10130 Identification of... the State subject to part 60, subpart B, of this chapter. Fluoride Emissions From Existing Primary...

40 CFR 62.10130 - Identification of plan-negative declaration.

Code of Federal Regulations, 2010 CFR

2010-07-01

... POLLUTANTS South Carolina Fluoride Emissions from Phosphate Fertilizer Plants § 62.10130 Identification of... the State subject to part 60, subpart B, of this chapter. Fluoride Emissions From Existing Primary...

Source apportionment of PM(2.5) in the harbour-industrial area of Brindisi (Italy): identification and estimation of the contribution of in-port ship emissions.

PubMed

Cesari, D; Genga, A; Ielpo, P; Siciliano, M; Mascolo, G; Grasso, F M; Contini, D

2014-11-01

Harbours are important for economic and social development of coastal areas but they also represent an anthropogenic source of emissions often located near urban centres and industrial areas. This increases the difficulties in distinguishing the harbour contribution with respect to other sources. The aim of this work is the characterisation of main sources of PM2.5 acting on the Brindisi harbour-industrial area, trying to pinpoint the contribution of in-port ship emissions to primary and secondary PM2.5. Brindisi is an important port-city of the Adriatic Sea considered a hot-spot for anthropogenic environmental pressures at National level. Measurements were performed collecting PM2.5 samples and characterising the concentrations of 23 chemical species (water soluble organic and inorganic carbon; major ions: SO4(2-), NO3(-), NH4(+), Cl(-), C2O4(2-), Na(+), K(+), Mg(2+), Ca(2+); and elements: Ni, Cu, V, Mn, As, Pb, Cr, Sb, Fe, Al, Zn, and Ti). These species represent, on average, 51.4% of PM2.5 and were used for source apportionment via PMF. The contributions of eight sources were estimated: crustal (16.4±0.9% of PM2.5), aged marine (2.6±0.5%), crustal carbonates (7.7±0.3%), ammonium sulphate (27.3±0.8%), biomass burning-fires (11.7±0.7%), traffic (16.4±1.7 %), industrial (0.4±0.3%) and a mixed source oil combustion-industrial including ship emissions in harbour (15.3±1.3%). The PMF did not separate the in-port ship emission contribution from industrial releases. The correlation of estimated contribution with meteorology showed directionality with an increase of oil combustion and sulphate contribution in the harbour direction with respect to the direction of the urban area and an increase of the V/Ni ratio. This allowed for the use of V as marker of primary ship contribution to PM2.5 (2.8%+/-1.1%). The secondary contribution of oil combustion to non-sea-salt-sulphate, nssSO4(2-), was estimated to be 1.3 μg/m(3) (about 40% of total nssSO4(2-) or 11% of PM2.5). Copyright © 2014 Elsevier B.V. All rights reserved.

Detection of the aromatic molecule benzonitrile (c-C6H5CN) in the interstellar medium

NASA Astrophysics Data System (ADS)

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

2018-01-01

Polycyclic aromatic hydrocarbons and polycyclic aromatic nitrogen heterocycles are thought to be widespread throughout the universe, because these classes of molecules are probably responsible for the unidentified infrared bands, a set of emission features seen in numerous Galactic and extragalactic sources. Despite their expected ubiquity, astronomical identification of specific aromatic molecules has proven elusive. We present the discovery of benzonitrile (c-C6H5CN), one of the simplest nitrogen-bearing aromatic molecules, in the interstellar medium. We observed hyperfine-resolved transitions of benzonitrile in emission from the molecular cloud TMC-1. Simple aromatic molecules such as benzonitrile may be precursors for polycyclic aromatic hydrocarbon formation, providing a chemical link to the carriers of the unidentified infrared bands.

40 CFR 62.9120 - Identification of plan-negative declaration.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Oklahoma Fluoride Emissions from Phosphate Fertilizer Plants § 62.9120 Identification of plan—negative.... [43 FR 51393, Nov. 3, 1978. Redesignated at 52 FR 3229, Feb. 3, 1987] Fluoride Emissions From Primary...

40 CFR 62.9120 - Identification of plan-negative declaration.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Oklahoma Fluoride Emissions from Phosphate Fertilizer Plants § 62.9120 Identification of plan—negative.... [43 FR 51393, Nov. 3, 1978. Redesignated at 52 FR 3229, Feb. 3, 1987] Fluoride Emissions From Primary...

Einstein X-ray observations of Herbig Ae/Be stars

NASA Technical Reports Server (NTRS)

Damiani, F.; Micela, G.; Sciortino, S.; Harnden, F. R., Jr.

1994-01-01

We have investigated the X-ray emission from Herbig Ae/Be stars, using the full set of Einstein Imaging Proportional Counter (IPC) observations. Of a total of 31 observed Herbig stars, 11 are confidently identified with X-ray sources, with four additonal dubious identifications. We have used maximum likelihood luminosity functions to study the distribution of X-ray luminosity, and we find that Be stars are significantly brighter in X-rays than Ae stars and that their X-ray luminosity is independent of projected rotational velocity v sin i. The X-ray emission is instead correlated with stellar bolometric luminosity and with effective temperature, and also with the kinetic luminosity of the stellar wind. These results seem to exclude a solar-like origin for the X-ray emission, a possibility suggested by the most recent models of Herbig stars' structure, and suggest an analogy with the X-ray emission of O (and early B) stars. We also observe correlations between X-ray luminosity and the emission at 2.2 microns (K band) and 25 microns, which strengthen the case for X-ray emission of Herbig stars originating in their circumstellar envelopes.

Comparison of methodologies estimating emissions of aircraft pollutants, environmental impact assessment around airports

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

Kurniawan, Jermanto S., E-mail: Jermanto.kurniawan@inrets.fr; Khardi, S., E-mail: Salah.khardi@inrets.f

2011-04-15

Air transportation growth has increased continuously over the years. The rise in air transport activity has been accompanied by an increase in the amount of energy used to provide air transportation services. It is also assumed to increase environmental impacts, in particular pollutant emissions. Traditionally, the environmental impacts of atmospheric emissions from aircraft have been addressed in two separate ways; aircraft pollutant emissions occurring during the landing and take-off (LTO) phase (local pollutant emissions) which is the focus of this study, and the non-LTO phase (global/regional pollutant emissions). Aircraft pollutant emissions are an important source of pollution and directly ormore » indirectly harmfully affect human health, ecosystems and cultural heritage. There are many methods to asses pollutant emissions used by various countries. However, using different and separate methodology will cause a variation in results, some lack of information and the use of certain methods will require justification and reliability that must be demonstrated and proven. In relation to this issue, this paper presents identification, comparison and reviews of some of the methodologies of aircraft pollutant assessment from the past, present and future expectations of some studies and projects focusing on emissions factors, fuel consumption, and uncertainty. This paper also provides reliable information on the impacts of aircraft pollutant emissions in short term and long term predictions.« less

Characterization and source identification of fine particulate matter in urban Beijing during the 2015 Spring Festival.

PubMed

Ji, Dongsheng; Cui, Yang; Li, Liang; He, Jun; Wang, Lili; Zhang, Hongliang; Wang, Wan; Zhou, Luxi; Maenhaut, Willy; Wen, Tianxue; Wang, Yuesi

2018-07-01

The Spring Festival (SF) is the most important holiday in China for family reunion and tourism. During the 2015 SF an intensive observation campaign of air quality was conducted to study the impact of the anthropogenic activities and the dynamic characteristics of the sources. During the study period, pollution episodes frequently occurred with 12days exceeding the Chinese Ambient Air Quality Standards for 24-h average PM 2.5 (75μg/m 3 ), even 8days with exceeding 150μg/m 3 . The daily maximum PM 2.5 concentration reached 350μg/m 3 while the hourly minimum visibility was <0.8km. Three pollution episodes were selected for detailed analysis including chemical characterization and diurnal variation of the PM 2.5 and its chemical composition, and sources were identified using the Positive Matrix Factorization model. The first episode occurring before the SF was characterized by more formation of SO 4 2- and NO 3 - and high crustal enrichment factors for Ag, As, Cd, Cu, Hg, Pb, Se and Zn and seven categories of pollution sources were identified, whereby vehicle emission contributed 38% to the PM 2.5 . The second episode occurring during the SF was affected heavily by large-scale firework emissions, which led to a significant increase in SO 4 2- , Cl - , OC, K and Ba; these emissions were the largest contributor to the PM 2.5 accounting for 36%. During the third episode occurring after the SF, SO 4 2- , NO 3 - , NH 4 + and OC were the major constituents of the PM 2.5 and the secondary source was the dominant source with a contribution of 46%. The results provide a detailed understanding on the variation in occurrence, chemical composition and sources of the PM 2.5 as well as of the gaseous pollutants affected by the change in anthropogenic activities in Beijing throughout the SF. They highlight the need for limiting the firework emissions during China's most important traditional festival. Copyright © 2018 Elsevier B.V. All rights reserved.

Application of genetic algorithm for the simultaneous identification of atmospheric pollution sources

NASA Astrophysics Data System (ADS)

Cantelli, A.; D'Orta, F.; Cattini, A.; Sebastianelli, F.; Cedola, L.

2015-08-01

A computational model is developed for retrieving the positions and the emission rates of unknown pollution sources, under steady state conditions, starting from the measurements of the concentration of the pollutants. The approach is based on the minimization of a fitness function employing a genetic algorithm paradigm. The model is tested considering both pollutant concentrations generated through a Gaussian model in 25 points in a 3-D test case domain (1000m × 1000m × 50 m) and experimental data such as the Prairie Grass field experiments data in which about 600 receptors were located along five concentric semicircle arcs and the Fusion Field Trials 2007. The results show that the computational model is capable to efficiently retrieve up to three different unknown sources.

X-ray Counterparts of Infrared Faint Radio Sources

NASA Astrophysics Data System (ADS)

Schartel, Norbert

2011-10-01

Infrared Faint Radio Sources (IFRS) are radio sources with extremely faint or even absent infrared emission in deep Spitzer Surveys. Models of their spectral energy distributions, the ratios of radio to infrared flux densities and their steep radio spectra strongly suggest that IFRS are AGN at high redshifts (2

Direct measurements of near-highway emissions in a high diesel environment

NASA Astrophysics Data System (ADS)

DeWitt, H. L.; Hellebust, S.; Temime-Roussel, B.; Ravier, S.; Polo, L.; Jacob, V.; Buisson, C.; Charron, A.; André, M.; Pasquier, A.; Besombes, J. L.; Jaffrezo, J. L.; Wortham, H.; Marchand, N.

2014-10-01

Diesel-powered passenger cars currently outnumber gasoline-powered cars in many countries, particularly in Europe. In France, diesel cars represented 61% of Light Duty Vehicles in 2011 and this percentage is still increasing (French Environment and Energy Management Agency, ADEME). As part of the September~2011 joint PM-DRIVE (Particulate Matter- DiRect and Indirect on-road Vehicular Emissions) and MOCOPO (Measuring and mOdeling traffic COngestion and POllution) field campaign, the concentration and high-resolution chemical composition of aerosols and volatile organic carbon (VOC) species were measured adjacent to a major urban highway south of Grenoble, France. Alongside these atmospheric measurements, detailed traffic data were collected from nearby traffic cameras and loop detectors, which allowed the identification of vehicle type and characteristics, traffic concentration, and traffic speed to be quantified and compared to measured aerosol and VOCs. Six aerosol age and source profiles were resolved using the positive matrix factorization (PMF) model on real-time high-resolution aerosol mass spectra. These six aerosol source/age categories included a hydrocarbon-like organic aerosol (HOA) commonly associated with primary vehicular emissions, a nitrogen containing aerosol (NOA) with a diurnal pattern similar to that of HOA, oxidized organic aerosol (OOA), and biomass burning aerosol (BBOA). While quantitatively separating the influence of diesel vs. gasoline proved impossible, a low HOA : black carbon ratio, similar to that measured in other high-diesel environments, and high levels of NOx, also indicative of diesel emissions, were observed. A comparison between these high-diesel environment measurements and measurements taken in low-diesel (North American) environments was examined and the potential feedback between vehicular emissions and SOA formation was probed. Although the measurement site was located next to a large source of primary emissions, which are typically found to have low oxygen incorporation, OOA was found to comprise the majority of the measured organic aerosol, and the measured OOA contained mainly modern carbon, not fossil-derived carbon. Thus, even in this heavily vehicular-emission impacted environment, photochemical processes, biogenic emissions, and aerosol oxidation dominated the overall organic aerosol mass measured during most of the campaign.

Volatile organic compounds concentrations during the construction process in newly-built timber-frame houses: source identification and emission kinetics.

PubMed

Plaisance, H; Vignau-Laulhere, J; Mocho, P; Sauvat, N; Raulin, K; Desauziers, V

2017-05-24

Building and furniture materials are known to be major sources of volatile organic compounds (VOCs) indoors. During the construction process, an introduced material can have a more or less long-term impact on the indoor air quality according to the building characteristics. In this study, field measurements were carried out at six construction stages in three energy-efficient timber-frame houses. Data analysis focused on the ten most abundant compounds found among an initial list of fifteen target VOCs, namely formaldehyde, acetaldehyde, hexanal, toluene, m/p-xylenes, ethylbenzene, styrene, α-pinene, 3-carene and d-limonene. The chemical compositions and concentration variation patterns were recorded. The results showed a high pollution count, with m/p-xylenes and ethylbenzene concentrations ranging from 1900 to 5100 μg m -3 occurring at the time of the structural work (representing more than 88% of the sum of the target VOCs). Emission tests done on a large number of materials used in the construction revealed that this pollution is due to the emissions from the polyurethane adhesive mastic used as a sealing material. The emission kinetics of polyurethane adhesive mastic was assessed alone and also within a material assembly reconstituting a room wall. The results showed that the superposition of materials led to a slowing down of the VOC emission process from polyurethane adhesive mastic, which explains the concentration decays recorded in houses during the construction process. At the final construction stage, the concentration levels were low for all compounds (the sums of the target VOCs were between 18 and 32 μg m -3 ), with the aldehydes (formaldehyde, acetaldehyde and hexanal) now becoming the major fraction in the chemical composition in the last stages of construction (representing 50-70% of the sum of the target VOCs). This is in agreement with the fact that the sources of aldehydes are the most numerous among the materials and have rather slow emission kinetics.

Modeling the Impact of Arctic Shipping Pollution on Air Quality off the Coast of Northern Norway

NASA Astrophysics Data System (ADS)

Thomas, J. L.; Law, K.; Marelle, L.; Raut, J.; Jalkanen, J.; Johansson, L.; Roiger, A.; Schlager, H.; Kim, J.; Reiter, A.; Weinzierl, B.; Rose, M.; Fast, J. D.

2013-12-01

As the Arctic is undergoing rapid and potentially irreversible changes, such as the shrinking and thinning of sea-ice cover, the levels of atmospheric pollution are expected to rise dramatically due to the emergence of local pollution sources including shipping. Shipping routes through the Arctic (such as Russia's Northern Sea Route) are already used as an alternative to the traditional global transit shipping routes. In summer 2012, the ACCESS (Arctic Climate Change, Economy, and Society) aircraft campaign focused on studying pollution sources off the coast of northern Norway to quantify emissions from shipping and other anthropogenic pollution sources. To complement these measurements, a regional chemical transport model is used to study the impact of shipping pollution on gas and aerosol concentrations in the region. WRF-Chem (The Weather Research and Forecasting Model with Chemistry, which simulates gas and aerosols simultaneously with meteorology) is run with real time shipping emissions from STEAM (Ship Traffic Emission Assessment Model) for July 2012. The STEAM model calculates gas and aerosol emissions of marine traffic based on the ship type and location provided by the Automatic Identification System (AIS). Use of real time position, speed, and ship specific information allows for development of emissions with very high spatial (1x1 km) and temporal (30 min) resolution, which are used in the regional model runs. STEAM emissions have been specifically generated for shipping off the coast of Norway during the entire ACCESS campaign period. Simulated ship plumes from high-resolution model runs are compared to aircraft measurements. The regional impact of current summertime shipping is also examined. At present, relatively light ship traffic off the coast of northern Norway results in only a small impact of shipping pollution on regional atmospheric chemistry. The impact of increased future shipping on regional atmospheric chemistry is also assessed.

Organic composition and source apportionment of fine aerosol at Monterrey, Mexico, based on organic markers

NASA Astrophysics Data System (ADS)

Mancilla, Y.; Mendoza, A.; Fraser, M. P.; Herckes, P.

2016-01-01

Primary emissions from anthropogenic and biogenic sources as well as secondary formation are responsible for the pollution levels of ambient air in major urban areas. These sources release fine particles into the air that negatively impact human health and the environment. Organic molecular markers, which are compounds that are unique to specific PM2.5 sources, can be utilized to identify the major emission sources in urban areas. In this study, 43 representative PM2.5 samples, for both daytime and nighttime periods, were built from individual samples collected in an urban site of the Monterrey metropolitan area (MMA) during the spring and fall of 2011 and 2012. The samples were analyzed for organic carbon, elemental carbon, and organic molecular markers. Several diagnostic tools were employed for the preliminary identification of emission sources. Organic compounds for eight compound classes were quantified. The n-alkanoic acids were the most abundant, followed by n-alkanes, wood smoke markers, and levoglucosan/alkenoic acids. Polycyclic aromatic hydrocarbons (PAHs) and hopanes were less abundant. The carbon preference index (0.7-2.6) for n-alkanes indicates a major contribution of anthropogenic and mixed sources during the fall and the spring, respectively. Hopanes levels confirmed the contribution from gasoline and diesel engines. In addition, the contribution of gasoline and diesel vehicle exhaust was confirmed and identified by the PAH concentrations in PM2.5. Diagnostic ratios of PAHs showed emissions from burning coal, wood, biomass, and other fossil fuels. The total PAHs and elemental carbon were correlated (r2 = 0.39-0.70) across the monitoring periods, reinforcing that motor vehicles are the major contributors of PAHs. Cholesterol levels remained constant during the spring and fall, showing evidence of the contribution of meat-cooking operations, while the isolated concentrations of levoglucosan suggested occasional biomass burning events. Finally, source attribution results obtained using the CMB (chemical mass balance) model indicate that emissions from motor vehicle exhausts are the most important, accounting for the 64 % of the PM2.5, followed by meat-cooking operations with 31 % The vegetative detritus and biomass burning had the smallest contribution (2.2 % of the PM2.5). To our knowledge, this is only the second study to explore the organic composition and source apportionment of fine organic aerosol based on molecular markers in Mexico and the first for the MMA. Particularly molecular marker were quantified by solvent extraction with dichloromethane, derivatization, and gas chromatography with mass spectrometry (GC/MS).

Characterization of selected volatile organic compounds, polycyclic aromatic hydrocarbons and carbonyl compounds at a roadside monitoring station

NASA Astrophysics Data System (ADS)

Ho, K. F.; Lee, S. C.; Chiu, Gloria M. Y.

Volatile organic compounds (VOCs), PAHs and carbonyl compounds are the major toxic components in Hong Kong. Emissions from motor vehicles have been one of the primary pollution sources in the metropolitan areas throughout Hong Kong for a long time. A 1-yr monitoring program for VOCs, PAHs and carbonyl compounds had been performed at a roadside urban station at Hong Kong Polytechnic University in order to determine the variations and correlations of each selected species (VOCs, PAHs and carbonyl compounds). This study is aimed to analyze toxic volatile organic compounds (benzene, toluene, ethylbenzene and xylene), two carbonyl compounds (formaldehyde, acetaldehyde), and selective polycyclic aromatic hydrocarbons. The monitoring program started from 16 April 1999 to 30 March 2000. Ambient VOC concentrations, many of which originate from the same sources as particulate PAHs and carbonyls compounds, show significant quantities of benzene, toluene and xylenes. Correlations and multivariate analysis of selected gaseous and particulate phase organic pollutants were performed. Source identification by principle component analysis and hierarchical cluster analysis allowed the identification of four sources (factors) for the roadside monitoring station. Factor 1 represents the effect of diesel vehicle exhaust. Factor 2 shows the contribution of aromatic compounds. Factor 3 explains photochemical products—formaldehyde and acetaldehyde. Factor 4 explains the effect of gasoline vehicle exhaust.

"X-Ray Transients in Star-Forming Regions" and "Hard X-Ray Emission from X-Ray Bursters"

NASA Technical Reports Server (NTRS)

Halpern, Jules P.; Kaaret, Philip

1999-01-01

This grant funded work on the analysis of data obtained with the Burst and Transient Experiment (BATSE) on the Compton Gamma-Ray Observatory. The goal of the work was to search for hard x-ray transients in star forming regions using the all-sky hard x-ray monitoring capability of BATSE. Our initial work lead to the discovery of a hard x-ray transient, GRO J1849-03. Follow-up observations of this source made with the Wide Field Camera on BeppoSAX showed that the source should be identified with the previously known x-ray pulsar GS 1843-02 which itself is identified with the x-ray source X1845-024 originally discovered with the SAS-3 satellite. Our identification of the source and measurement of the outburst recurrence time, lead to the identification of the source as a Be/X-ray binary with a spin period of 94.8 s and an orbital period of 241 days. The funding was used primarily for partial salary and travel support for John Tomsick, then a graduate student at Columbia University. John Tomsick, now Dr. Tomsick, received his Ph.D. from Columbia University in July 1999, based partially on results obtained under this investigation. He is now a postdoctoral research scientist at the University of California, San Diego.

The X-Ray Counterpart to LAT PSR J2021+4026 and Its Interesting Spectrum

NASA Technical Reports Server (NTRS)

Weisskopf, Martin C.; Becker, W.; Carraminana, A.; De Luca, A.; Dormandy, M.; Harding, A.; Kanbach, G.; O'Dell, S. L.; Parkinson, P. Saz; Ray, P.;

Speciation of organic fractions does matter for aerosol source apportionment. Part 2: Intensive short-term campaign in the Paris area (France).

PubMed

Srivastava, D; Favez, O; Bonnaire, N; Lucarelli, F; Haeffelin, M; Perraudin, E; Gros, V; Villenave, E; Albinet, A

2018-09-01

The present study aimed at performing PM 10 source apportionment, using positive matrix factorization (PMF), based on filter samples collected every 4h at a sub-urban station in the Paris region (France) during a PM pollution event in March 2015 (PM 10 >50μgm -3 for several consecutive days). The PMF model allowed to deconvolve 11 source factors. The use of specific primary and secondary organic molecular markers favoured the determination of common sources such as biomass burning and primary traffic emissions, as well as 2 specific biogenic SOA (marine+isoprene) and 3 anthropogenic SOA (nitro-PAHs+oxy-PAHs+phenolic compounds oxidation) factors. This study is probably the first one to report the use of methylnitrocatechol isomers as well as 1-nitropyrene to apportion secondary OA linked to biomass burning emissions and primary traffic emissions, respectively. Secondary organic carbon (SOC) fractions were found to account for 47% of the total OC. The use of organic molecular markers allowed the identification of 41% of the total SOC composed of anthropogenic SOA (namely, oxy-PAHs, nitro-PAHs and phenolic compounds oxidation, representing 15%, 9%, 11% of the total OC, respectively) and biogenic SOA (marine+isoprene) (6% in total). Results obtained also showed that 35% of the total SOC originated from anthropogenic sources and especially PAH SOA (oxy-PAHs+nitro-PAHs), accounting for 24% of the total SOC, highlighting its significant contribution in urban influenced environments. Anthropogenic SOA related to nitro-PAHs and phenolic compounds exhibited a clear diurnal pattern with high concentrations during the night indicating the prominent role of night-time chemistry but with different chemical processes involved. Copyright © 2018 Elsevier B.V. All rights reserved.

THE IDENTIFICATION OF THE X-RAY COUNTERPART TO PSR J2021+4026

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

Weisskopf, Martin C.; Elsner, Ronald F.; O'Dell, Stephen L.

2011-12-10

We report the probable identification of the X-ray counterpart to the {gamma}-ray pulsar PSR J2021+4026 using imaging with the Chandra X-ray Observatory Advanced CCD Imaging Spectrometer and timing analysis with the Fermi satellite. Given the statistical and systematic errors, the positions determined by both satellites are coincident. The X-ray source position is R.A. 20{sup h}21{sup m}30.{sup s}733, decl. +40 Degree-Sign 26'46.''04 (J2000) with an estimated uncertainty of 1.''3 combined statistical and systematic error. Moreover, both the X-ray to {gamma}-ray and the X-ray to optical flux ratios are sensible assuming a neutron star origin for the X-ray flux. The X-ray sourcemore » has no cataloged infrared-to-visible counterpart and, through new observations, we set upper limits to its optical emission of i' > 23.0 mag and r' > 25.2 mag. The source exhibits an X-ray spectrum with most likely both a power law and a thermal component. We also report on the X-ray and visible light properties of the 43 other sources detected in our Chandra observation.« less

The Atacama Cosmology Telescope: Extragalactic Sources at 148 GHz in the 2008 Survey

NASA Technical Reports Server (NTRS)

Marriage, T. A.; Juin, J. B.; Lin, Y. T.; Marsden, D.; Nolta, M. R.; Partridge, B.; Ade, P. A. R.; Aguirre, P.; Amiri, M.; Appel, J. W.;

40 CFR 62.5150 - Identification of plan.

Code of Federal Regulations, 2010 CFR

2010-07-01

...) APPROVAL AND PROMULGATION OF STATE PLANS FOR DESIGNATED FACILITIES AND POLLUTANTS Maryland Landfill Gas Emissions from Existing Municipal Solid Waste Landfills (section 111(d) Plan) § 62.5150 Identification of..., Emissions Guidelines for Municipal Solid Waste Landfills. ...

Impacts of changes in precursor emissions from the San Francisco Bay Area on ozone in the North Central Coast and San Joaquin Valley air basins. Final report

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

Douglas, S.G.; Stoeckenius, T.E.; Austin, B.S.

1991-02-01

The study examined the effect of emissions reductions in the San Francisco Bay Area (SFBA) on ozone levels in the North Central Coast (NCC) and San Joaquin Valley (SJV) air basins. It included an emissions trends analysis for the SFBA, NCC, and SJV air basins; identification of possible transport days and an analysis of ozone trends in both the source and receptor basins on transport and no-transport days; and calculation of interbasin pollutant fluxes using air-quality modeling results. The emissions trends analysis indicated that the SFBA achieved large decreases in emissions of reactive organic gases (ROG) and oxides of nitrogenmore » (NOx) between 1979 and 1988. Despite the large decreases in emissions no significant ozone trends were observed on either transport or no-transport days. Ozone concentrations at the downwind monitors were higher on transport days. Results of the flux plane calculations indicate that elimination of SFBA emissions would significantly reduce ozone concentrations in the NCC and SJV during meteorological conditions conducive to transport and that the lower concentrations in the downwind air basins would be due primarily to a reduction in the amount of precursor pollutants that are transport from the SFBA to the receptor basins.« less

Identification of indicator congeners and evaluation of emission pattern of polychlorinated naphthalenes in industrial stack gas emissions by statistical analyses.

PubMed

Liu, Guorui; Cai, Zongwei; Zheng, Minghui; Jiang, Xiaoxu; Nie, Zhiqiang; Wang, Mei

2015-01-01

Identifying marker congeners of unintentionally produced polychlorinated naphthalenes (PCNs) from industrial thermal sources might be useful for predicting total PCN (∑2-8PCN) emissions by the determination of only indicator congeners. In this study, potential indicator congeners were identified based on the PCN data in 122 stack gas samples from over 60 plants involved in more than ten industrial thermal sources reported in our previous case studies. Linear regression analyses identified that the concentrations of CN27/30, CN52/60, and CN66/67 correlated significantly with ∑2-8PCN (R(2)=0.77, 0.80, and 0.58, respectively; n=122, p<0.05), which might be good candidates for indicator congeners. Equations describing relationships between indicators and ∑2-8PCN were established. The linear regression analyses involving 122 samples showed that the relationships between the indicator congeners and ∑2-8PCN were not significantly affected by factors such as industry types, raw materials used, or operating conditions. Hierarchical cluster analysis and similarity calculations for the 122 stack gas samples were adopted to group those samples and evaluating their similarity and difference based on the PCN homolog distributions from different industrial thermal sources. Generally, the fractions of less chlorinated homologs comprised of di-, tri-, and tetra-homologs were much higher than that of more chlorinated homologs for up to 111 stack gas samples contained in group 1 and 2, which indicating the dominance of lower chlorinated homologs in stack gas from industrial thermal sources. Copyright © 2014 Elsevier Ltd. All rights reserved.

Contributions and source identification of biogenic and anthropogenic hydrocarbons to secondary organic aerosols at Mt. Tai in 2014.

PubMed

Zhu, Yanhong; Yang, Lingxiao; Kawamura, Kimitaka; Chen, Jianmin; Ono, Kaori; Wang, Xinfeng; Xue, Likun; Wang, Wenxing

2017-01-01

Ambient fine particulate matter (PM 2.5 ) and volatile organic compounds (VOCs) collected at Mt. Tai in summer 2014 were analysed and the data were used to identify the contribution of biogenic and anthropogenic hydrocarbons to secondary organic aerosols (SOA) and their sources and potential source areas in high mountain regions. Compared with those in 2006, the 2014 anthropogenic SOA tracers in PM 2.5 aerosols and VOC species related to vehicular emissions exhibited higher concentrations, whereas the levels of biogenic SOA tracers were lower, possibly due to decreased biomass burning. Using the SOA tracer and parameterisation method, we estimated the contributions from biogenic and anthropogenic VOCs, respectively. The results showed that the average concentration of biogenic SOA was 1.08 ± 0.51 μg m -3 , among which isoprene SOA tracers were dominant. The anthropogenic VOC-derived SOA were 7.03 ± 1.21 μg m -3 and 1.92 ± 1.34 μg m -3 under low- and high-NO x conditions, respectively, and aromatics made the greatest contribution. However, the sum of biogenic and anthropogenic SOA only contributed 18.1-49.1% of the total SOA. Source apportionment by positive matrix factorisation (PMF) revealed that secondary oxidation and biomass burning were the major sources of biogenic SOA tracers. Anthropogenic aromatics mainly came from solvent use, fuel and plastics combustion and vehicular emissions. However, for > C6 alkanes and cycloalkanes, vehicular emissions and fuel and plastics combustion were the most important contributors. The potential source contribution function (PSCF) identified the Bohai Sea Region (BSR) as the major source area for organic aerosol compounds and VOC species at Mt. Tai. Copyright © 2016 Elsevier Ltd. All rights reserved.

Color sensitive silicon photomultiplers with micro-cell level encoding for DOI PET detectors

NASA Astrophysics Data System (ADS)

Shimazoe, Kenji; Koyama, Akihiro; Takahashi, Hiroyuki; Ganka, Thomas; Iskra, Peter; Marquez Seco, Alicia; Schneider, Florian; Wiest, Florian

2017-11-01

There have been many studies on Depth Of Interaction (DOI) identification for high resolution Positron Emission Tomography (PET) systems, including those on phoswich detectors, double-sided readout, light sharing methods, and wavelength discrimination. The wavelength discrimination method utilizes the difference in wavelength of stacked scintillators and requires a color sensitive photodetector. Here, a new silicon photomultiplier (SiPM) coupled to a color filter (colorSiPM) was designed and fabricated for DOI detection. The fabricated colorSiPM has two anode readouts that are sensitive to blue and green color. The colorSiPM's response and DOI identification capability for stacked GAGG and LYSO crystals are characterized. The fabricated colorSiPM is sensitive enough to detect a peak of 662 keV from a 137 Cs source.

Identification of Campylobacter infection in chickens from volatile faecal emissions.

PubMed

Garner, Catherine E; Smith, Stephen; Elviss, Nicola C; Humphrey, Tom J; White, Paul; Ratcliffe, Norman M; Probert, Christopher S

2008-06-01

Volatile organic compounds from chicken faeces were investigated as biomarkers for Campylobacter infection. Campylobacter are major poultry-borne zoonotic pathogens, colonizing the avian intestinal tract. Chicken faeces are the principal source of contamination of carcasses. Fresh faeces were collected on farm sites, and Campylobacter status established microbiologically. Volatile organic compounds were pre-concentrated from the headspace above 71 separate faecal samples using solid-phase microextraction and separated and identified by gas chromatography/mass spectrometry. A Campylobacter-specific profile was identified using six of the extracted volatile organic compounds. The model developed reliably identified the presence or absence of Campylobacter in >95% of chickens. The volatile biomarker identification approach for assessing avian infection is a novel approach to enhancing biosecurity in the poultry industry and should reduce the risk of disease transmission to humans.

The Strontium Filament within the Homunculus of Eta Carinae

NASA Technical Reports Server (NTRS)

Gull, Theodore R.; Hartman, H.; Zethson, T.; Johansson, S.; Ishibashi, K.; Davidson, K.; Fisher, Richard R. (Technical Monitor)

2001-01-01

During a series of HST/STIS observations of Eta Carinae and associated ejecta, we noticed a peculiar emission filament located a few arcseconds north of the central source. While bright in nebular standards, it is submerged in a sea of scattered starlight until moderately high dispersion, long-slit spectroscopy with the STIS (R- 8000) brings the emission lines out. The initial spectrum, centered on 6768A with the STIS G750M grating, led to identification of twenty lines from singly-Ionized species including [Sr II], [Fe II], [Ti II], [Ni II], [Mn II], and [Co II] (Zethson, etal., 2001, AJ 122,322). No Balmer emission is detected from this filament and the Fe II 2507,9 lines, known to be pumped by Lyman alpha radiation in other regions near the central source, are not detected. Followup observations have led to detection of hundreds more emission lines from iron group elements in neutral and singly-ionized states. Thus far all are excited by less than 10 eV. This peculiar nebular emission is thought to be due to very intense stellar radiation, stripped of uv flux shortward of Lyman alpha, bathing a neutral structure. We are systematically identifying the many lines (over 90% identified) and measuring line intensities that will then be modeled to determine excitation mechanisms, temperature and density. Two [Sr II] and two Sr II lines have now been measured. Bautista, etal. (in preparation) have modeled the strontium flux ratios and find that large radiation fluxes and/or high strontium abundances may account for the detected emission. These observations were supported by STIS GTO funding and GO funding through the STScI

Kalman-filtered compressive sensing for high resolution estimation of anthropogenic greenhouse gas emissions from sparse measurements.

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

Ray, Jaideep; Lee, Jina; Lefantzi, Sophia

2013-09-01

The estimation of fossil-fuel CO2 emissions (ffCO2) from limited ground-based and satellite measurements of CO2 concentrations will form a key component of the monitoring of treaties aimed at the abatement of greenhouse gas emissions. The limited nature of the measured data leads to a severely-underdetermined estimation problem. If the estimation is performed at fine spatial resolutions, it can also be computationally expensive. In order to enable such estimations, advances are needed in the spatial representation of ffCO2 emissions, scalable inversion algorithms and the identification of observables to measure. To that end, we investigate parsimonious spatial parameterizations of ffCO2 emissions whichmore » can be used in atmospheric inversions. We devise and test three random field models, based on wavelets, Gaussian kernels and covariance structures derived from easily-observed proxies of human activity. In doing so, we constructed a novel inversion algorithm, based on compressive sensing and sparse reconstruction, to perform the estimation. We also address scalable ensemble Kalman filters as an inversion mechanism and quantify the impact of Gaussian assumptions inherent in them. We find that the assumption does not impact the estimates of mean ffCO2 source strengths appreciably, but a comparison with Markov chain Monte Carlo estimates show significant differences in the variance of the source strengths. Finally, we study if the very different spatial natures of biogenic and ffCO2 emissions can be used to estimate them, in a disaggregated fashion, solely from CO2 concentration measurements, without extra information from products of incomplete combustion e.g., CO. We find that this is possible during the winter months, though the errors can be as large as 50%.« less

A stable isotope model for combined source apportionment and degradation quantification of environmental pollutants

NASA Astrophysics Data System (ADS)

Lutz, Stefanie; Van Breukelen, Boris

2014-05-01

Natural attenuation can represent a complementary or alternative approach to engineered remediation of polluted sites. In this context, compound specific stable isotope analysis (CSIA) has proven a useful tool, as it can provide evidence of natural attenuation and assess the extent of in-situ degradation based on changes in isotope ratios of pollutants. Moreover, CSIA can allow for source identification and apportionment, which might help to identify major emission sources in complex contamination scenarios. However, degradation and mixing processes in aquifers can lead to changes in isotopic compositions, such that their simultaneous occurrence might complicate combined source apportionment (SA) and assessment of the extent of degradation (ED). We developed a mathematical model (stable isotope sources and sinks model; SISS model) based on the linear stable isotope mixing model and the Rayleigh equation that allows for simultaneous SA and quantification of the ED in a scenario of two emission sources and degradation via one reaction pathway. It was shown that the SISS model with CSIA of at least two elements contained in the pollutant (e.g., C and H in benzene) allows for unequivocal SA even in the presence of degradation-induced isotope fractionation. In addition, the model enables precise quantification of the ED provided degradation follows instantaneous mixing of two sources. If mixing occurs after two sources have degraded separately, the model can still yield a conservative estimate of the overall extent of degradation. The SISS model was validated against virtual data from a two-dimensional reactive transport model. The model results for SA and ED were in good agreement with the simulation results. The application of the SISS model to field data of benzene contamination was, however, challenged by large uncertainties in measured isotope data. Nonetheless, the use of the SISS model provided a better insight into the interplay of mixing and degradation processes at the field site, as it revealed the prevailing contribution of one emission source and a low overall ED. The model can be extended to a larger number of sources and sinks. It may aid in forensics and natural attenuation assessment of soil, groundwater, surface water, or atmospheric pollution.

Estimation of Supraglacial Dust and Debris Geochemical Composition via Satellite Reflectance and Emissivity

NASA Technical Reports Server (NTRS)

Casey, Kimberly Ann; Kaab, Andreas

2012-01-01

We demonstrate spectral estimation of supraglacial dust, debris, ash and tephra geochemical composition from glaciers and ice fields in Iceland, Nepal, New Zealand and Switzerland. Surface glacier material was collected and analyzed via X-ray fluorescence spectroscopy (XRF) and X-ray diffraction (XRD) for geochemical composition and mineralogy. In situ data was used as ground truth for comparison with satellite derived geochemical results. Supraglacial debris spectral response patterns and emissivity-derived silica weight percent are presented. Qualitative spectral response patterns agreed well with XRF elemental abundances. Quantitative emissivity estimates of supraglacial SiO2 in continental areas were 67% (Switzerland) and 68% (Nepal), while volcanic supraglacial SiO2 averages were 58% (Iceland) and 56% (New Zealand), yielding general agreement. Ablation season supraglacial temperature variation due to differing dust and debris type and coverage was also investigated, with surface debris temperatures ranging from 5.9 to 26.6 C in the study regions. Applications of the supraglacial geochemical reflective and emissive characterization methods include glacier areal extent mapping, debris source identification, glacier kinematics and glacier energy balance considerations.

Challenges in atmospheric monitoring of areal emission sources - an Open-path Fourier transform infrared (OP-FTIR) spectroscopic experience report

NASA Astrophysics Data System (ADS)

Schuetze, C.; Sauer, U.; Dietrich, P.

2015-12-01

Reliable detection and assessment of near-surface CO2 emissions from natural or anthropogenic sources require the application of various monitoring tools at different spatial scales. Especially, optical remote sensing tools for atmospheric monitoring have the potential to measure integrally CO2 emissions over larger scales (> 10.000m2). Within the framework of the MONACO project ("Monitoring approach for geological CO2 storage sites using a hierarchical observation concept"), an integrative hierarchical monitoring concept was developed and validated at different field sites with the aim to establish a modular observation strategy including investigations in the shallow subsurface, at ground surface level and the lower atmospheric boundary layer. The main aims of the atmospheric monitoring using optical remote sensing were the observation of the gas dispersion in to the near-surface atmosphere, the determination of maximum concentration values and identification of the main challenges associated with the monitoring of extended emission sources with the proposed methodological set up under typical environmental conditions. The presentation will give an overview about several case studies using the integrative approach of Open-Path Fourier Transform Infrared spectroscopy (OP FTIR) in combination with in situ measurements. As a main result, the method was validated as possible approach for continuous monitoring of the atmospheric composition, in terms of integral determination of GHG concentrations and to identify target areas which are needed to be investigated more in detail. Especially the data interpretation should closely consider the micrometeorological conditions. Technical aspects concerning robust equipment, experimental set up and fast data processing algorithms have to be taken into account for the enhanced automation of atmospheric monitoring.

Newly Uncovered Large-Scale Component of the Northern Jet in R Aqr

NASA Astrophysics Data System (ADS)

Montez, Rodolfo; Karovska, Margarita; Nichols, Joy S.; Kashyap, Vinay

2017-06-01

R Aqr is a symbiotic system comprised a compact white dwarf and Mira giant star. The interaction of these stars is responsible for the presence of a two-sided jet structure that is seen across the electromagnetic spectrum. X-ray emission from the jet was first discovered in 2000 with an observation by the Chandra X-ray Observatory. Since then follow-up observations have traced the evolution of the X-ray emission from the jet and a central compact source. In X-rays, the NE jet is brighter than the SW jet, but the full extent of the SW jet was larger - before it began fading below the detection threshold. However, we have uncovered evidence for large-scale emission associated with the NE jet that matches the extent of the SW jet. The emission has escaped previous identification because it is near the detection threshold, but it has been present since the first 2000 observation and clearly evolves in subsequent observations. We present our study of the emission from this component of the NE jet, its relationship to multiwavelength observations, and how it impacts our interpretation of the jet-phenomenon in R Aqr.

Analysis of RF emissions from laser induced breakdown of atmospheric air and metals

NASA Astrophysics Data System (ADS)

Paturi, Prem Kiran; Lakshmi, Vinoth Kumar; Elle, Manikanta; Chelikani, Leela

2013-10-01

The low frequency (RF, microwave) emissions from laser produced plasma (LPP) are of great interest because of their variety of applications. The RF waves emitted by the nanosecond LPP of atmospheric air and metal (Al, Cu) targets were detected using antennas over frequency ranges (30 MHz-18 GHz) and were monitored using a spectrum analyzer (3 Hz-50 GHz). With different target materials, the dominant emission lines were observed to fall in different specific frequency ranges within the detection limit. The emissions from Cu were in the higher frequency range (100-200 MHz) than that of Al (30-100 MHz) may be due to the higher electron density of Cu, which contributes to the LPP conductivity. From the LPP of atmospheric air, the RF output was found to be increasing with the input laser energy up to certain value, beyond which almost no emission was observed. This effect is attributed to the modification in the net induced dipole moment due to the multiple plasma sources in the LPP at higher input laser energies. The detected radiation was observed to be dependent on laser and antenna polarization. Further studies may lead to an efficient technique for material identification from the RF characteristic peaks.

Point-source and diffuse high-energy neutrino emission from Type IIn supernovae

NASA Astrophysics Data System (ADS)

Petropoulou, M.; Coenders, S.; Vasilopoulos, G.; Kamble, A.; Sironi, L.

2017-09-01

Type IIn supernovae (SNe), a rare subclass of core collapse SNe, explode in dense circumstellar media that have been modified by the SNe progenitors at their last evolutionary stages. The interaction of the freely expanding SN ejecta with the circumstellar medium gives rise to a shock wave propagating in the dense SN environment, which may accelerate protons to multi-PeV energies. Inelastic proton-proton collisions between the shock-accelerated protons and those of the circumstellar medium lead to multimessenger signatures. Here, we evaluate the possible neutrino signal of Type IIn SNe and compare with IceCube observations. We employ a Monte Carlo method for the calculation of the diffuse neutrino emission from the SN IIn class to account for the spread in their properties. The cumulative neutrino emission is found to be ˜10 per cent of the observed IceCube neutrino flux above 60 TeV. Type IIn SNe would be the dominant component of the diffuse astrophysical flux, only if 4 per cent of all core collapse SNe were of this type and 20-30 per cent of the shock energy was channeled to accelerated protons. Lower values of the acceleration efficiency are accessible by the observation of a single Type IIn SN as a neutrino point source with IceCube using up-going muon neutrinos. Such an identification is possible in the first year following the SN shock breakout for sources within 20 Mpc.

Characterization of Fine Airborne Particulate Collected in Tokyo and Major Atmospheric Emission Sources by Using Single Particle Measurement of SEM-EDX

NASA Astrophysics Data System (ADS)

Sato, K.; Iijima, A.; Furuta, N.

2008-12-01

In our long-term monitoring of size-classified Airborne Particulate Matter (APM) in Tokyo since 1995, it had been demonstrated that toxic elements such as As, Se, Cd, Sb and Pb were extremely enriched in fine APM (PM2.5). However, in that study, total sampled APM on a filter was digested with acids, and thus only averaged elemental composition in fine APM could be obtained. One of the effective methods to determine the origin of APM is single particle measurement by using SEM-EDX. By using characteristic shapes observed by SEM and marker elements contained in APM measured by EDX, detailed information for source identification can be obtained. In this study, fine APM (PM2.5) was collected at various locations such as roadside, diesel vehicle exhaust, a heavy oil combustion plant and a waste incineration plant as well as ambient atmosphere in Tokyo, and characteristics of fine particles that will be utilized for identification of emission sources are elucidated. Fine particles can be classified into 3 main characteristic shape groups; edge-shaped, cotton-like and spherical. Shape of particles collected in a heavy oil combustion plant and a waste incineration plant was mostly spherical, and these particles may be associated with thermal process. Diesel exhaust particles were predominantly cotton-like which may consist of coagulated nano-sized particles. Most of brake abrasion dusts were edge-shaped, which may be associated with mechanical abrasion of brake pads. In the elemental analysis of fine particles, high concentrations of Sb, Cu, Ti and Ba were detected in brake abrasion dusts. Since these elements are major constituents of brake pads, these can be used for marker elements of brake abrasion dusts. High concentration of C was detected in diesel exhaust particles and oil combustion particles, and thus C can be used for marker elements of their origin. Furthermore, high concentrations of C, Ca and K were detected in fly ash from a waste incineration plant, which may be associated with emission from biomass combustion.

Import, use, and emissions of PCBs in Switzerland from 1930 to 2100.

PubMed

Glüge, Juliane; Steinlin, Christine; Schalles, Simone; Wegmann, Lukas; Tremp, Josef; Breivik, Knut; Hungerbühler, Konrad; Bogdal, Christian

2017-01-01

Polychlorinated biphenyls (PCBs) are persistent organic compounds that are ubiquitously found in the environment. Their use and manufacture were restricted or banned in many countries in the 1970-1980s, however, they still persist in the antroposphere, the environment and in biota worldwide today. Conventions like the Convention on Long-range Transboundary Air Pollution encourage or bind the member parties to annually submit emission inventories of regulated air pollutants. Unfortunately, several member states have not yet reported PCB emissions. The identification and quantification of stocks and emissions sources is, however, an important precondition to handle and remove the remaining reservoirs of PCBs and, thus, to be able to reduce emissions and subsequently environmental exposure. Here, we estimate past, present, and future emissions of PCBs to air in Switzerland and provide emission factors for all relevant emission categories. Switzerland hereby represents a typical developed industrial country, and most of the assumptions and parameters presented here can be used to calculate PCB emission also for other countries. PCB emissions to air are calculated using a dynamic mass flow and emissions model for Switzerland, which is run for the years 1930-2100. The results point out the importance of the use of PCBs in open applications, which have largely been previously overlooked. Additionally, we show that PCBs will persist in applications during the coming decades with ongoing emissions. Especially the use of PCBs in open applications will cause Swiss emissions to remain above 100 kg PCB per year, even after the year 2030. Our developed model is available in Excel/VBA and can be downloaded with this article.

Automated Collection of Real-Time Alerts of Citizens as a Useful Tool to Continuously Monitor Malodorous Emissions.

PubMed

Brattoli, Magda; Mazzone, Antonio; Giua, Roberto; Assennato, Giorgio; de Gennaro, Gianluigi

2016-02-26

The evaluation of odor emissions and dispersion is a very arduous topic to face; the real-time monitoring of odor emissions, the identification of chemical components and, with proper certainty, the source of annoyance represent a challenge for stakeholders such as local authorities. The complaints of people, often not systematic and variously distributed, in general do not allow us to quantify the perceived annoyance. Experimental research has been performed to detect and evaluate olfactory annoyance, based on field testing of an innovative monitoring methodology grounded in automatic recording of citizen alerts. It has been applied in Taranto, in the south of Italy where a relevant industrial area is located, by using Odortel(®) for automated collection of citizen alerts. To evaluate its reliability, the collection system has been integrated with automated samplers, able to sample odorous air in real time, according to the citizen alerts of annoyance and, moreover, with meteorological data (especially the wind direction) and trends in odor marker compounds, recorded by air quality monitoring stations. The results have allowed us, for the first time, to manage annoyance complaints, test their reliability, and obtain information about the distribution and entity of the odor phenomena, such that we were able to identify, with supporting evidence, the source as an oil refinery plant.

Carbon footprint of organic beef meat from farm to fork: A case study of short supply chain.

PubMed

Vitali, A; Grossi, G; Martino, G; Bernabucci, U; Nardone, A; Lacetera, N

2018-04-24

Sustainability of food systems is one of the big challenges of humans kind in the next years. Local food networks, especially the organic ones, are growing worldwide and few information is known about their carbon footprint. This study was aimed to assess greenhouse gases (GHG) emissions associated to organic local beef supply chain with a cradle to grave approach. The study pointed out an overall burden of 24.46 kg CO 2 eq./kg of cooked meat. The breeding and fattening phase accounted 86% of the total emissions and resulted the main hot spot throughout the whole chain. Enteric methane emission was the greatest source of GHG at farm gate (47%). The consumption of meat at home was the second hot spot throughout the chain (9%) and cooking process was the main source within this stage (72%). Retail and slaughtering activities accounted for 4.1% and 1.1% on the whole supply chain, respectively. The identification of GHG hot spots associated to organic beef meat produced and consumed in a local food network may stimulate the debate on environmental issues among the actors involved in the network and direct them toward processes, choices and habits less carbon polluting. This article is protected by copyright. All rights reserved.

Hybrid Air Quality Modeling Approach For Use in the Near ...

EPA Pesticide Factsheets

The Near-road EXposures to Urban air pollutant Study (NEXUS) investigated whether children with asthma living in close proximity to major roadways in Detroit, MI, (particularly near roadways with high diesel traffic) have greater health impacts associated with exposure to air pollutants than those living farther away. A major challenge in such health and exposure studies is the lack of information regarding pollutant exposure characterization. Air quality modeling can provide spatially and temporally varying exposure estimates for examining relationships between traffic-related air pollutants and adverse health outcomes. This paper presents a hybrid air quality modeling approach and its application in NEXUS in order to provide spatial and temporally varying exposure estimates and identification of the mobile source contribution to the total pollutant exposure. Model-based exposure metrics, associated with local variations of emissions and meteorology, were estimated using a combination of the AERMOD and R-LINE dispersion models, local emission source information from the National Emissions Inventory, detailed road network locations and traffic activity, and meteorological data from the Detroit City Airport. The regional background contribution was estimated using a combination of the Community Multiscale Air Quality (CMAQ) model and the Space/Time Ordinary Kriging (STOK) model. To capture the near-road pollutant gradients, refined “mini-grids” of model recep

40 CFR 62.8870 - Identification of plan.

Code of Federal Regulations, 2010 CFR

2010-07-01

...) APPROVAL AND PROMULGATION OF STATE PLANS FOR DESIGNATED FACILITIES AND POLLUTANTS Ohio Landfill Gas Emissions from Existing Municipal Solid Waste Landfills § 62.8870 Identification of plan. The Ohio State Implementation Plan for implementing the Federal Municipal Solid Waste Landfill Emission Guidelines including...

40 CFR 62.3330 - Identification of plan.

Code of Federal Regulations, 2010 CFR

2010-07-01

...) APPROVAL AND PROMULGATION OF STATE PLANS FOR DESIGNATED FACILITIES AND POLLUTANTS Illinois Landfill Gas Emissions from Existing Municipal Solid Waste Landfills § 62.3330 Identification of plan. The Illinois Plan for implementing the Federal Municipal Solid Waste Landfill Emission Guidelines to control air...

The impact of speciated VOCs on regional ozone increment derived from measurements at the UK EMEP supersites between 1999 and 2012

NASA Astrophysics Data System (ADS)

Malley, C. S.; Braban, C. F.; Dumitrean, P.; Cape, J. N.; Heal, M. R.

2015-03-01

The impact of 27 volatile organic compounds (VOC) on the regional O3 increment was investigated using measurements made at the UK EMEP supersites Harwell (1999-2001 and 2010-2012) and Auchencorth (2012). Ozone at these sites is representative of rural O3 in south-east England and northern UK, respectively. Monthly-diurnal regional O3 increment was defined as the difference between the regional and hemispheric background O3 concentrations, respectively derived from oxidant vs. NOx correlation plots, and cluster analysis of back trajectories arriving at Mace Head, Ireland. At Harwell, which had substantially greater regional ozone increments than at Auchencorth, variation in the regional O3 increment mirrored afternoon depletion of VOCs due to photochemistry (after accounting for diurnal changes in boundary layer mixing depth, and weighting VOC concentrations according to their photochemical ozone creation potential). A positive regional O3 increment occurred consistently during the summer, during which time afternoon photochemical depletion was calculated for the majority of measured VOCs, and to the greatest extent for ethene and m + p-xylene. This indicates that, of the measured VOCs, ethene and m + p-xylene emissions reduction would be most effective in reducing the regional O3 increment, but that reductions in a larger number of VOCs would be required for further improvement. The VOC diurnal photochemical depletion was linked to the sources of the VOC emissions through the integration of gridded VOC emissions estimates over 96 h air-mass back trajectories. This demonstrated that the effectiveness of VOC gridded emissions for use in measurement and modelling studies is limited by the highly aggregated nature of the 11 SNAP source sectors in which they are reported, as monthly variation in speciated VOC trajectory emissions did not reflect monthly changes in individual VOC diurnal photochemical depletion. Additionally, the major VOC emission source sectors during elevated regional O3 increment at Harwell were more narrowly defined through disaggregation of the SNAP emissions to 91 NFR codes (i.e. sectors 3D2 (domestic solvent use), 3D3 (other product use) and 2D2 (food and drink)). However, spatial variation in the contribution of NFR sectors to parent SNAP emissions could only be accounted for at the country level. Hence, the future reporting of gridded VOC emissions in source sectors more highly disaggregated than currently (e.g. to NFR codes) would facilitate a more precise identification of those VOC sources most important for mitigation of the impact of VOCs on O3 formation. In summary, this work presents a clear methodology for achieving a coherent VOC regional-O3-impact chemical climate using measurement data and explores the effect of limited emission and measurement species on the understanding of the regional VOC contribution to O3 concentrations.

The impact of speciated VOCs on regional ozone increment derived from measurements at the UK EMEP supersites between 1999 and 2012

NASA Astrophysics Data System (ADS)

Malley, C. S.; Braban, C. F.; Dumitrean, P.; Cape, J. N.; Heal, M. R.

2015-07-01

The impact of 27 volatile organic compounds (VOCs) on the regional O3 increment was investigated using measurements made at the UK EMEP supersites Harwell (1999-2001 and 2010-2012) and Auchencorth (2012). Ozone at these sites is representative of rural O3 in south-east England and northern UK, respectively. The monthly-diurnal regional O3 increment was defined as the difference between the regional and hemispheric background O3 concentrations, respectively, derived from oxidant vs. NOx correlation plots, and cluster analysis of back trajectories arriving at Mace Head, Ireland. At Harwell, which had substantially greater regional O3 increments than Auchencorth, variation in the regional O3 increment mirrored afternoon depletion of anthropogenic VOCs due to photochemistry (after accounting for diurnal changes in boundary layer mixing depth, and weighting VOC concentrations according to their photochemical ozone creation potential). A positive regional O3 increment occurred consistently during the summer, during which time afternoon photochemical depletion was calculated for the majority of measured VOCs, and to the greatest extent for ethene and m+p-xylene. This indicates that, of the measured VOCs, ethene and m+p-xylene emissions reduction would be most effective in reducing the regional O3 increment but that reductions in a larger number of VOCs would be required for further improvement. The VOC diurnal photochemical depletion was linked to anthropogenic sources of the VOC emissions through the integration of gridded anthropogenic VOC emission estimates over 96 h air-mass back trajectories. This demonstrated that one factor limiting the effectiveness of VOC gridded emissions for use in measurement and modelling studies is the highly aggregated nature of the 11 SNAP (Selected Nomenclature for Air Pollution) source sectors in which they are reported, as monthly variation in speciated VOC trajectory emissions did not reflect monthly changes in individual VOC diurnal photochemical depletion. Additionally, the major VOC emission source sectors during elevated regional O3 increment at Harwell were more narrowly defined through disaggregation of the SNAP emissions to 91 NFR (Nomenclature for Reporting) codes (i.e. sectors 3D2 (domestic solvent use), 3D3 (other product use) and 2D2 (food and drink)). However, spatial variation in the contribution of NFR sectors to parent SNAP emissions could only be accounted for at the country level. Hence, the future reporting of gridded VOC emissions in source sectors more highly disaggregated than currently (e.g. to NFR codes) would facilitate a more precise identification of those VOC sources most important for mitigation of the impact of VOCs on O3 formation. In summary, this work presents a clear methodology for achieving a coherent VOC, regional-O3-impact chemical climate using measurement data and explores the effect of limited emission and measurement species on the understanding of the regional VOC contribution to O3 concentrations.

Chandra Deep X-ray Observation of a Typical Galactic Plane Region and Near-Infrared Identification

NASA Technical Reports Server (NTRS)

Ebisawa, K.; Tsujimoto, M.; Paizis, A.; Hamaguichi, K.; Bamba, A.; Cutri, R.; Kaneda, H.; Maeda, Y.; Sato, G.; Senda, A.

2004-01-01

Using the Chandra Advanced CCD Imaging Spectrometer Imaging array (ACIS-I), we have carried out a deep hard X-ray observation of the Galactic plane region at (l,b) approx. (28.5 deg,0.0 deg), where no discrete X-ray source has been reported previously. We have detected 274 new point X-ray sources (4 sigma confidence) as well as strong Galactic diffuse emission within two partidly overlapping ACIS-I fields (approx. 250 sq arcmin in total). The point source sensitivity was approx. 3 x 10(exp -15)ergs/s/sq cm in the hard X-ray band (2-10 keV and approx. 2 x 10(exp -16) ergs/s/sq cm in the soft band (0.5-2 keV). Sum of all the detected point source fluxes account for only approx. 10 % of the total X-ray fluxes in the field of view. In order to explain the total X-ray fluxes by a superposition of fainter point sources, an extremely rapid increase of the source population is required below our sensitivity limit, which is hardly reconciled with any source distribution in the Galactic plane. Therefore, we conclude that X-ray emission from the Galactic plane has truly diffuse origin. Only 26 point sources were detected both in the soft and hard bands, indicating that there are two distinct classes of the X-ray sources distinguished by the spectral hardness ratio. Surface number density of the hard sources is only slightly higher than observed at the high Galactic latitude regions, strongly suggesting that majority of the hard X-ray sources are active galaxies seen through the Galactic plane. Following the Chandra observation, we have performed a near-infrared (NIR) survey with SOFI at ESO/NTT to identify these new X-ray sources. Since the Galactic plane is opaque in NIR, we did not see the background extragalactic sources in NIR. In fact, only 22 % of the hard sources had NIR counterparts which are most likely to be Galactic origin. Composite X-ray energy spectrum of those hard X-ray sources having NIR counterparts exhibits a narrow approx. 6.7 keV iron emission line, which is a signature of Galactic quiescent cataclysmic variables (CVs).

Advanced Low Emissions Subsonic Combustor Study

NASA Technical Reports Server (NTRS)

Smith, Reid

1998-01-01

Recent advances in commercial and military aircraft gas turbines have yielded significant improvements in fuel efficiency and thrust-to-weight ratio, due in large part to increased combustor operating pressures and temperatures. However, the higher operating conditions have increased the emission of oxides of nitrogen (NOx), which is a pollutant with adverse impact on the atmosphere and environment. Since commercial and military aircraft are the only important direct source of NOx emissions at high altitudes, there is a growing consensus that considerably more stringent limits on NOx emissions will be required in the future for all aircraft. In fact, the regulatory communities have recently agreed to reduce NOx limits by 20 percent from current requirements effective in 1996. Further reductions at low altitude, together with introduction of limits on NOx at altitude, are virtual certainties. In addition, the U.S. Government recently conducted hearings on the introduction of federal fees on the local emission of pollutants from all sources, including aircraft. While no action was taken regarding aircraft in this instance, the threat of future action clearly remains. In these times of intense and growing international competition, the U.S. le-ad in aerospace can only be maintained through a clear technological dominance that leads to a product line of maximum value to the global airline customer. Development of a very low NOx combustor will be essential to meet the future needs of both the commercial and military transport markets, if additional economic burdens and/or operational restrictions are to be avoided. In this report, Pratt & Whitney (P&W) presents the study results with the following specific objectives: Development of low-emissions combustor technologies for advances engines that will enter into service circa 2005, while producing a goal of 70 percent lower NOx emissions, compared to 1996 regulatory levels. Identification of solution approaches to barriers to the productization and economic viability of the low-emissions technologies. Preparation of these technologies to facilitate an annular rig high-pressure demonstration.

The assessment of source attribution of soil pollution in a typical e-waste recycling town and its surrounding regions using the combined organic and inorganic dataset.

PubMed

Luo, Jie; Qi, Shihua; Xie, Xianming; Gu, X W Sophie; Wang, Jinji

2017-01-01

Guiyu is a well-known electronic waste dismantling and recycling town in south China. Concentrations and distribution of the 21 mineral elements and 16 polycyclic aromatic hydrocarbons (PAHs) collected there were evaluated. Principal component analyses (PCA) applied to the data matrix of PAHs in the soil extracted three major factors explaining 85.7% of the total variability identified as traffic emission, coal combustion, and an unidentified source. By using metallic or metalloid element concentrations as variables, five principal components (PCs) were identified and accounted for 70.4% of the information included in the initial data matrix, which can be denoted as e-waste dismantling-related contamination, two different geological origins, anthropogenic influenced source, and marine aerosols. Combining the 21 metallic and metalloid element datasets with the 16 PAH concentrations can narrow down the coarse source and decrease the unidentified contribution to soil in the present study and therefore effectively assists the source identification process.

Very old and very young compact objects: X-ray studies of galactic globular clusters and recent core-collapse supernovae

NASA Astrophysics Data System (ADS)

Pooley, David Aaron

2003-09-01

This thesis comprises the results of two distinct areas of research, namely, X-ray studies of Galactic globular clusters and X-ray studies of recent core collapse supernovae. My analyses of the Chandra X-ray Observatory observations of the globular clusters NGC 6752 and NGC 6440 revealed as many low- luminosity X-ray sources as was in the entire census of globular cluster sources with the previous best X-ray imaging instrument, Röntgensatellit. In the observation of NGC 6752, I detect 6 X-ray sources within the 10''.5 core radius and 13 more within the 115' half-mass radius down to a limiting luminosity of Lx ≈ 1030 ergs s -1 for cluster sources. Based on a reanalysis of archival data from the Hubble Space Telescope and the Australia Telescope Compact Array, I make 12 optical identifications and one radio identification. Based on X- ray and optical properties of the identifications, I find 10 likely cataclysmic variables (CVs), 1 3 likely RS CVn or BY Dra systems, and 1 or 2 possible background objects. Of the 7 sources for which no optical identifications were made, one was detected in the archival radio data, and another was found to be a millisecond pulsar. Of the remaining sources, I expect that ˜2 4 are background objects and that the rest are either CVs or millisecond pulsars whose radio emission has not been detected. These and other Chandra results on globular clusters indicate that the dozens of CVs per cluster expected by theoretical arguments are being found. Based upon X-ray luminosities and colors, I conclude that there are 4 5 likely quiescent low-mass X-ray binaries and that most of the other sources are cataclysmic variables. I compare these results to Chandra results from other globular clusters and find the X-ray luminosity functions differ among the clusters. Observations of the Type II-P (plateau) Supernova (SN) 1999em and Type IIn (narrow emission line) SN 1998S have enabled estimation of the profile of the SN ejecta, the structure of the circumstellar medium (CSM) established by the pre-SN stellar wind, and the nature of the shock interaction. SN 1999em is the first Type II-P detected at both X-ray and radio wavelengths. It is the least radio luminous and one of the least X-ray luminous SNe ever detected (except for the unusual and very close SN 1987A). My analysis of the Chandra X- ray data indicate non-radiative interaction of SN ejecta with a power-law density profile (ρ ∝ r-n with n ˜ 7) for a pre-SN wind with a low mass-loss rate of ˜2 × 10-6 M⊙ yr-1 for a wind velocity of 10 km s-1 , in agreement with radio mass-loss rate estimates. The Chandra data show an unexpected, temporary rise in the 0.4 2.0 keV X-ray flux at ˜100 days after explosion. My analysis of SN 1998S yielded the first X-ray spectrum of a supernova in which numerous heavy element emission features (Ne, Al, Si, S, Ar, Fe) were present. Spectral fits to the Chandra data show that these heavy elements are overabundant with respect to solar values. I compare the observed elemental abundances and abundance ratios to theoretical calculations and find that our data are consistent with a progenitor mass of approximately 15 20 M⊙ if the heavy element ejecta are radially mixed out to a high velocity. (Copies available exclusively from MIT Libraries, Rm. 14-0551, Cambridge, MA 02139-4307. Ph. 617-253-5668; Fax 617-253-1690.) (Abstract shortened by UMI.)

Identification of urban gas leaks and evaluation of methane emission inventories using mobile measurements

NASA Astrophysics Data System (ADS)

Zazzeri, Giulia; Lowry, Dave; Fisher, Rebecca E.; France, James L.; Butler, Dominique; Lanoisellé, Mathias; Nisbet, Euan G.

2017-04-01

Leakages from the natural gas distribution network, power plants and refineries account for the 10% of national methane emissions in the UK (http://naei.defra.gov.uk/), and are identified as a major source of methane in big conurbations (e.g. Townsend-Small et al., 2012; Phillips et al., 2013). The National Atmospheric Emission Inventories (NAEI) website provides a list of gas installations, but emissions from gas leakage, which in the inventories are estimated on the basis of the population distribution, are difficult to predict, which makes their estimation highly uncertain. Surveys with a mobile measurement system (Zazzeri et al., 2015) were carried out in the London region for detection of fugitive natural gas and in other sites in the UK (i.e. Bacton, Southampton, North Yorkshire) to identify emissions from various gas installations. The methane isotopic analysis of air samples collected during the surveys, using the methodology in Zazzeri et al. (2015), allows the calculation of the δ13C signature characterising natural gas in the UK. The isotopic value of the natural gas supply to SE London has changed a little in recent years, being close to -34 ‰ over 1998-99 period (Lowry et al., 2001) and close to -36 ‰ since at least 2002. Emissions from gas installations, such as pumping stations in NE England (-41 ± 2 ‰ ) were detected, but some of them were not listed in the inventories. Furthermore, the spatial distribution of the gas leaks identified during the surveys in the London region does not coincide with the distribution suggested by the inventories. By locating both small gas leaks and emissions from large gas installations, we can verify how these methane sources are targeted by national emission inventories. Lowry, D., Holmes, C.W., Rata, N.D., O'Brien, P., and Nisbet, E.G., 2001, London methane emissions: Use of diurnal changes in concentration and δ13C to identify urban sources and verify inventories: Journal of Geophysical Research: Atmospheres, v. 106, p. 7427-7448 Phillips, N. G., Ackley, R., Crosson, E. R., Down, A., Hutyra, L. R., Brondfield, M., Karr, J. D., Zhao, K., and Jackson, R. B., 2013, Mapping urban pipeline leaks: Methane leaks across Boston: Environmental Pollution, v. 173, p. 1-4 Townsend-Small, A., Tyler, S. C., Pataki, D. E., Xu, X., and Christensen, L. E., 2012, Isotopic measurements of atmospheric methane in Los Angeles, California, USA: Influence of "fugitive" fossil fuel emissions: Journal of Geophysical Research: Atmospheres, v. 117, no. D7 Zazzeri, G., Lowry, D., Fisher, R., France, J., Lanoisellé, M., and Nisbet, E., 2015, Plume mapping and isotopic characterisation of anthropogenic methane sources: Atmospheric Environment, v. 110, p. 151-162

40 CFR 62.3660 - Identification of plan.

Code of Federal Regulations, 2010 CFR

2010-07-01

...) APPROVAL AND PROMULGATION OF STATE PLANS FOR DESIGNATED FACILITIES AND POLLUTANTS Indiana Control of Air Emissions from Existing Commercial and Industrial Solid Waste Incinerator Units § 62.3660 Identification of plan. On December 20, 2002, Indiana submitted a plan to control emissions from Commercial and...

Electrically-detected ESR in silicon nanostructures inserted in microcavities

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

Bagraev, Nikolay; Danilovskii, Eduard; Gets, Dmitrii

2014-02-21

We present the first findings of the new electrically-detected electron spin resonance technique (EDESR), which reveal the point defects in the ultra-narrow silicon quantum wells (Si-QW) confined by the superconductor δ- barriers. This technique allows the ESR identification without application of an external cavity, as well as a high frequency source and recorder, and with measuring the only response of the magnetoresistance, with internal GHz Josephson emission within frameworks of the normal-mode coupling (NMC) caused by the microcavities embedded in the Si-QW plane.

EPA Region 1 - Map Layers for Valley ID Tool (Hosted Feature Service)

EPA Pesticide Factsheets

The Valley Service Feature Layer hosts spatial data for EPA Region 1's Valley Identification Tool. These layers contain attribute information added by EPA R1 GIS Center to help identify populated valleys:- Fac_2011NEI: Pollution sources selected from the National Emissions Inventory (EPA, 2011).- NE_Towns_PopValleys: New England Town polygons (courtesy USGS), with Population in Valleys and Population Density in Valleys calculated by EPA R1 GIS, from 2010 US Census blocks. - VT_E911: Vermont residences (courtesy VT Center for Geographic Information E-911).

The White Dwarf Mass and the Accretion Rate of Recurrent Novae: An X-ray Perspective

NASA Technical Reports Server (NTRS)

Mukai, Koji; Sokoloski, Jennifer L.; Nelson, Thomas; Luna, Gerardo J. M.

2011-01-01

We present recent results of quiescent X-ray observations of recurrent novae (RNe) and related objects. Several RNe are luminous hard X-ray sources in quiescence, consistent with accretion onto a near Chandrasekhar mass white dwarf. Detection of similar hard X-ray emissions in old novae and other cataclysmic variables may lead to identification of additional RN candidates. On the other hand, other RNe are found to be comparatively hard X-ray faint. We present several scenarios that may explain this dichotomy, which should be explored further.

SDSS-IV MaNGA: the spectroscopic discovery of strongly lensed galaxies

NASA Astrophysics Data System (ADS)

Talbot, Michael S.; Brownstein, Joel R.; Bolton, Adam S.; Bundy, Kevin; Andrews, Brett H.; Cherinka, Brian; Collett, Thomas E.; More, Anupreeta; More, Surhud; Sonnenfeld, Alessandro; Vegetti, Simona; Wake, David A.; Weijmans, Anne-Marie; Westfall, Kyle B.

2018-06-01

We present a catalogue of 38 spectroscopically detected strong galaxy-galaxy gravitational lens candidates identified in the Sloan Digital Sky Survey IV (SDSS-IV). We were able to simulate narrow-band images for eight of them demonstrating evidence of multiple images. Two of our systems are compound lens candidates, each with two background source-planes. One of these compound systems shows clear lensing features in the narrow-band image. Our sample is based on 2812 galaxies observed by the Mapping Nearby Galaxies at APO (MaNGA) integral field unit (IFU). This Spectroscopic Identification of Lensing Objects (SILO) survey extends the methodology of the Sloan Lens ACS Survey (SLACS) and BOSS Emission-Line Survey (BELLS) to lower redshift and multiple IFU spectra. We searched ˜1.5 million spectra, of which 3065 contained multiple high signal-to-noise ratio background emission-lines or a resolved [O II] doublet, that are included in this catalogue. Upon manual inspection, we discovered regions with multiple spectra containing background emission-lines at the same redshift, providing evidence of a common source-plane geometry which was not possible in previous SLACS and BELLS discovery programs. We estimate more than half of our candidates have an Einstein radius ≳ 1.7 arcsec, which is significantly greater than seen in SLACS and BELLS. These larger Einstein radii produce more extended images of the background galaxy increasing the probability that a background emission-line will enter one of the IFU spectroscopic fibres, making detection more likely.

Radio emission in the directions of cD and related galaxies in poor clusters. III. VLA observations at 20 cm

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

Burns, J.O.; White, R.A.; Hough, D.H.

1981-01-01

VLA radio maps and optical identifications of a sample of sources in the directions of 21 Yerkes poor cluster fields are presented. The majority of the cluster radio sources are associated with the dominant D or cD galaxies (approx.70%). Our analysis of dominant galaxies in rich and poor clusters indicates that these giant galaxies are much more often radio emitters (approx.25% of cD's are radio active in the poor clusters), have steeper radio spectra, and have simpler radio morphologies (i.e., double or other linear structure) than other less bright ellipticals. A strong continuum of radio properties in cD galaxies ismore » seen from rich to poor clusters. We speculate that the location of these dominant galaxies at the cluster centers (i.e., at the bottom of a deep, isolated gravitational potential well) is the crucial factor in explaining their multifrequency activity. We briefly discuss galaxy cannibalism and gas infall models as fueling mechanisms for the observed radio and x-ray emission.« less

Radio emission in the directions of cD and related galaxies in poor clusters. III - VLA observations at 20 cm

NASA Technical Reports Server (NTRS)

Burns, J. O.; White, R. A.; Hough, D. H.

1981-01-01

VLA radio maps and optical identifications of a sample of sources in the directions of 21 Yerkes poor cluster fields are presented. The majority of the cluster radio sources are associated with the dominant D or cD galaxies (approximately 70 percent). Our analysis of dominant galaxies in rich and poor clusters indicates that these giant galaxies are much more often radio emitters (approximately 25 percent of cD's are radio active in the poor clusters), have steeper radio spectra, and have simpler radio morphologies (i.e., double or other linear structure) than other less bright ellipticals. A strong continuum of radio properties in cD galaxies is seen from rich to poor clusters. It is speculated that the location of these dominant galaxies at the cluster centers (i.e., at the bottom of a deep, isolated gravitational potential well) is the crucial factor in explaining their multifrequency activity. Galaxy cannibalism and gas infall models as fueling mechanisms for the observed radio and X-ray emission are discussed

40 CFR 62.4950 - Identification of plan-negative declaration.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Maine Fluoride Emissions from Phosphate Fertilizer Plants § 62.4950 Identification of plan—negative... that there are no existing phosphate fertilizer plants in the state subject to part 60, subpart B of... Gases, Organic Compounds and Nitrogen Oxide Emissions From Existing Municipal Waste Combustors With the...

40 CFR 62.12320 - Identification of plan-negative declaration.

Code of Federal Regulations, 2014 CFR

2014-07-01

... POLLUTANTS Wisconsin Control of Air Emissions from Hospital/medical/infectious Waste Incinerators § 62.12320 Identification of plan—negative declaration. On July 15, 2013, the Wisconsin Department of Natural Resources.../Infectious Waste Incinerators (HMIWI) units in the State of Wisconsin subject to the emissions guidelines at...

40 CFR 62.4950 - Identification of plan-negative declaration.

Code of Federal Regulations, 2014 CFR

2014-07-01

... Maine Fluoride Emissions from Phosphate Fertilizer Plants § 62.4950 Identification of plan—negative... that there are no existing phosphate fertilizer plants in the state subject to part 60, subpart B of... Gases, Organic Compounds and Nitrogen Oxide Emissions From Existing Municipal Waste Combustors With the...

40 CFR 62.4950 - Identification of plan-negative declaration.

Code of Federal Regulations, 2012 CFR

2012-07-01

... Maine Fluoride Emissions from Phosphate Fertilizer Plants § 62.4950 Identification of plan—negative... that there are no existing phosphate fertilizer plants in the state subject to part 60, subpart B of... Gases, Organic Compounds and Nitrogen Oxide Emissions From Existing Municipal Waste Combustors With the...

40 CFR 62.4950 - Identification of plan-negative declaration.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Maine Fluoride Emissions from Phosphate Fertilizer Plants § 62.4950 Identification of plan—negative... that there are no existing phosphate fertilizer plants in the state subject to part 60, subpart B of... Gases, Organic Compounds and Nitrogen Oxide Emissions From Existing Municipal Waste Combustors With the...

40 CFR 62.4950 - Identification of plan-negative declaration.

Code of Federal Regulations, 2013 CFR

2013-07-01

... Maine Fluoride Emissions from Phosphate Fertilizer Plants § 62.4950 Identification of plan—negative... that there are no existing phosphate fertilizer plants in the state subject to part 60, subpart B of... Gases, Organic Compounds and Nitrogen Oxide Emissions From Existing Municipal Waste Combustors With the...

Catalogue of isolated emission episodes in gamma-ray bursts from Fermi, Swift and BATSE

NASA Astrophysics Data System (ADS)

Charisi, M.; Márka, S.; Bartos, I.

2015-04-01

We report a comprehensive catalogue of emission episodes within long gamma-ray bursts (GRBs) that are separated by a quiescent period during which gamma-ray emission falls below the background level. We use a fully automated identification method for an unbiased, large-scale and expandable search. We examine a comprehensive sample of long GRBs from the BATSE (Burst and Transient Source Experiment), Swift and Fermi missions, assembling a total searched set of 2710 GRBs, the largest catalogue of isolated emission episodes so far. Our search extends out to [-1000 s, 750 s] around the burst trigger, expanding the covered time interval beyond previous studies and far beyond the nominal durations (T90) of most bursts. We compare our results to previous works by identifying pre-peak emission (or precursors), defined as isolated emission periods prior to the episode with the highest peak luminosity of the burst. We also systematically search for similarly defined periods after the burst's peak emission. We find that the pre-peak and post-peak emission periods are statistically similar, possibly indicating a common origin. For the analysed GRBs, we identify 24 per cent to have more than one isolated emission episode, with 11 per cent having at least one pre-peak event and 15 per cent having at least one post-peak event. We identify GRB activity significantly beyond their T90, which can be important for understanding the central engine activity as well as, e.g. gravitational-wave searches.

Characterisation of Black Carbon (BC) mixing state and flux in Beijing using single particle measurements.

NASA Astrophysics Data System (ADS)

Joshi, Rutambhara; Liu, Dantong; Allan, James; Coe, Hugh; Flynn, Michael; Broda, Kurtis; Olfert, Jason; Irwin, Martin; Sun, Yele; Fu, Pingqing; Wang, Junfeng; Ge, Xinlei; Langford, Ben; Nemitz, Eiko; Mullinger, Neil

2017-04-01

BC is generated by the incomplete combustion of carbonaceous fuels and it is an important component of fine PM2.5. In the atmosphere BC particles have a complex structure and its mixing state has crucial impact on optical properties. Quantifying the sources and emissions of black carbon in urban environments is important and presently uncertain, particularly in megacities undergoing rapid growth and change in emissions. During the winter of 2016 (10th Nov-10th Dec) the BC was characterised as part of a large joint UK-China field experiment in Beijing. This paper focuses on understanding the mixing state of BC as well as identification and quantification of BC sources. We used a combination of a Centrifugal Particle Mass Analyser (CPMA) and a Single Particle Soot Photometer (SP2) to uniquely quantify the morphology independent mass of single refractory BC particles and their coating content. The CPMA allows us to select pre-charged aerosol particles according to their mass to charge ratio and the SP2 provides information on the mass of refractory BC through a laser-induced incandescence method. Furthermore, another SP2 was used to measure the BC flux at 100m height using the Eddy Covariance method. We have successfully gathered 4 weeks of continuous measurements which include several severe pollution events in Beijing. Here we present preliminary results, characterising the distribution of coating mass on BC particles in Beijing and linking this to the main sources of BC in the city. We will provide initial estimates of the BC flux over a several kilometre footprint. Such analysis will provide important information for the further investigation of source distribution, emission, lifetime and optical properties of BC under complex environments in Beijing.

Discovery of low-redshift X-ray selected quasars - New clues to the QSO phenomenon

NASA Technical Reports Server (NTRS)

Grindlay, J. E.; Forman, W. R.; Steiner, J. E.; Canizares, C. R.; Mcclintock, J. E.

1980-01-01

The identification of six X-ray sources discovered by the Einstein Observatory with X-ray quasars is reported, and the properties of these X-ray selected quasars are discussed. The four high-latitude fields of 1 sq deg each in which the Einstein imaging proportional counter detected serendipitous X-ray sources at intermediate exposures of 10,000 sec were observed by 4-m and 1.5-m telescopes, and optical sources with uv excesses and emission line spectra typical of many low-redshift quasars and Seyfert 1 galaxies were found within the 1-arcsec error boxes of the X-ray sources. All six quasars identified were found to be radio quiet, with low redshift and relatively faint optical magnitudes, and to be similar in space density, colors and magnitude versus redshift relation to an optically selected sample at the same mean magnitude. X-ray luminosity was found to be well correlated with both continuum and broad-line emission luminosities for the known radio-quiet quasars and Seyfert 1 galaxies, and it was observed that the five objects with the lowest redshifts have very similar X-ray/optical luminosity ratios despite tenfold variations in X-ray luminosity. It is concluded that photoionization by a continuum extending to X-ray energies is the dominant excitation mechanism in radio-quiet quasars.

Combining MODIS, MISR, CALIOP, OMI, AERONET, and Models to Identify the Spatial and Temporal Distribution, Characterization, and Magnitude of Missing Urban and Wildfire Emissions Sources throughout Asia.

NASA Astrophysics Data System (ADS)

Cohen, J. B.

2016-12-01

Due to intense and changing levels of emissions as well as highly non-linear chemical processing, the concentrations of aerosols and thus their impacts are not well known. Urban areas consist of the majority of the emissions of these species and their precursors over large periods of time, while wildfires contribute very large spikes, concentrated in space and over a period of weeks to months. Yet due to urban and economic expansion, as well as clouds amd low intensity burning, the spatial and temporal profiles of these species are changing, with both new sources appearing and old sources decreasing. New work incorporates measurements at different spatial andboptical resolutions from MODIS, MISR, and OMI, coupled with new sampling approaches with CALIOP and AERONET to search for, characterize, and spatially and temporally constrain aerosols. An advanced modeling system including aerosol chemistry, physics, optics, and transport, using a multi-modal and both externally mixed and core-shell mixing is used to quantify the magnitudes of these missing sources. Comparisons between the model and additional dozens of ground stations show extreme improvement when these new sources are included. This new approach is shown to identify new source regions of emissions, many of which were previously non-urbanized or were not found to contain any fire hotspots. In addition, the use of new models run under conditions including both missing local sources from regions such as the expanded urban areas in Southeast and East Asia and advanced chemical and aerosol routines, allow for a comprehensive analysis to be performed. The impacts of insitu chemistry, horizontal, and vertical transport of species, both on the Regional and Continental scale are also included. It is shown that for proper identification, especially on intra-annual and inter-annual variations, this approach is a large improvement throughout Asia, ranging from India, to Indonesia, to China and Japan. Results specific to Southern China and Southeast East Asia demonstrate the additional importance of the climate, as additional variations are identified. Such knowledge can allow us to better understand the consequences and impacts of the rapid ongoing changes occurring in these regions.

Ozone-Depleting Gases in the Atmosphere: Results From 28 Years of Measurements by the NOAA Climate Monitoring and Diagnostics Laboratory (CMDL)

NASA Astrophysics Data System (ADS)

Hurst, D. F.; Elkins, J. W.; Montzka, S. A.; Butler, J. H.; Dutton, G. S.; Hall, B. D.; Mondeel, D. J.; Moore, F. L.; Nance, J. D.; Romashkin, P. A.; Thompson, T. M.

2005-12-01

Back in 1978, NOAA/CMDL initiated the weekly filling of flasks at CMDL observatories in Alaska, Hawaii, American Samoa, and Antarctica for analyses of CFC-11, CFC-12 and N2O in the home laboratory. A decade later, each observatory was outfitted with an automated gas chromatograph to make routine, in situ measurements of these three source gases plus methyl chloroform and carbon tetrachloride. Both measurement programs are ongoing, having expanded over the years to include methyl halides and substitutes for regulated halocarbons, to presently account for 95% of the total burden of long-lived Cl and Br believed to enter the stratosphere. These long-term monitoring data have been assimilated into temporal records of the global tropospheric burdens of ozone-depleting chlorine and bromine which are critical input to models that predict future trends in stratospheric ozone. Other information pivotal to ozone projections, such as the atmospheric lifetimes of source gases, stratospheric entry values for total chlorine and total bromine, and identification of the stratospheric sink regions for long-lived source gases, has been gained from in situ measurements by NOAA/CMDL instruments aboard NASA high-altitude aircraft (ER-2 and WB-57) and balloons since 1991. Though CMDL's routine monitoring activities provide important historical records of halogenated source gases in the atmosphere, significant inaccuracies in ozone projections may propagate from the uncertain estimates of impending emissions of ozone-depleting gases. Scenarios of future halocarbon emissions require substantial assumptions about past and pending compliance with the Montreal Protocol, and the sizes and release rates of existing global reservoirs (banks) of halocarbons. Recent work by CMDL has focused on quantifying halocarbon bank emission rates in Russia, the USA, and Canada through geographically extensive measurements aboard trains and low-altitude aircraft. The USA and Canada results indicate that globally significant emissions continued to emanate from these two countries in 2003, more than 7 years after the Montreal Protocol-mandated production phase-out. Large-scale, measurement-based emission estimates such as these provide important checks of our understanding of contemporary halocarbon emissions and will undoubtedly help to improve the accuracy of projected future halocarbon abundances and ozone recovery rates.

Inter-comparison of receptor models for PM source apportionment: Case study in an industrial area

NASA Astrophysics Data System (ADS)

Viana, M.; Pandolfi, M.; Minguillón, M. C.; Querol, X.; Alastuey, A.; Monfort, E.; Celades, I.

2008-05-01

Receptor modelling techniques are used to identify and quantify the contributions from emission sources to the levels and major and trace components of ambient particulate matter (PM). A wide variety of receptor models are currently available, and consequently the comparability between models should be evaluated if source apportionment data are to be used as input in health effects studies or mitigation plans. Three of the most widespread receptor models (principal component analysis, PCA; positive matrix factorization, PMF; chemical mass balance, CMB) were applied to a single PM10 data set (n=328 samples, 2002-2005) obtained from an industrial area in NE Spain, dedicated to ceramic production. Sensitivity and temporal trend analyses (using the Mann-Kendall test) were applied. Results evidenced the good overall performance of the three models (r2>0.83 and α>0.91×between modelled and measured PM10 mass), with a good agreement regarding source identification and high correlations between input (CMB) and output (PCA, PMF) source profiles. Larger differences were obtained regarding the quantification of source contributions (up to a factor of 4 in some cases). The combined application of different types of receptor models would solve the limitations of each of the models, by constructing a more robust solution based on their strengths. The authors suggest the combined use of factor analysis techniques (PCA, PMF) to identify and interpret emission sources, and to obtain a first quantification of their contributions to the PM mass, and the subsequent application of CMB. Further research is needed to ensure that source apportionment methods are robust enough for application to PM health effects assessments.

Identification of two hard X-ray emitting Be stars using the HEAO 1 scanning modulation collimator

NASA Technical Reports Server (NTRS)

Steiner, J. E.; Ferrara, A.; Garcia, M.; Patterson, J.; Schwartz, D. A.; Warwick, R. S.; Watson, M. G.; Mcclintock, J. E.

1984-01-01

Using precise positions from the HEAO 1 Scanning Modulation Collimator experiment, two hard X-ray sources, 4U 0728 - 25 = 3A 0726 - 260 and 4U 2206 + 54 = 3A 2206 + 543, are identified with early-type stars. In both cases broad (10 A FWHM) H-alpha emission is detected. The UBV colors suggest that the optical counterparts are main-sequence B0-B2 stars at 2-6 kpc, implying a mean X-ray luminosity of order 10 to the 35th ergs/sq cm s (2-10 keV). The X-ray emission in both cases is highly variable, and it is suggested that they belong to the class of X-ray emitting Be stars, containing a neutron star in a widely separated binary system.

Levels and Sources of Volatile Organic Compounds in Homes of Children with Asthma

PubMed Central

Chin, Jo-Yu; Godwin, Christopher; Parker, Edith; Robins, Thomas; Lewis, Toby; Harbin, Paul; Batterman, Stuart

2014-01-01

Many volatile organic compounds (VOCs) are classified as known or possible carcinogens, irritants and toxicants, and VOC exposure has been associated with the onset and exacerbation of asthma. This study characterizes VOC levels in 126 homes of children with asthma in Detroit, Michigan, USA. The total target VOC concentration ranged from 14 to 2,274 μg/m3 (mean = 150 μg/m3; median = 91 μg/m3); 56 VOCs were quantified; and d-limonene, toluene, p, m-xylene and ethyl acetate had the highest concentrations. Based on the potential for adverse health effects, priority VOCs included naphthalene, benzene, 1,4-dichlorobenzene, isopropylbenzene, ethylbenzene, styrene, chloroform, 1,2-dichloroethane, tetrachloroethene and trichloroethylene. Concentrations varied mostly due to between-residence and seasonal variation. Identified emission sources included cigarette smoking, solvent-related emissions, renovations, household products and pesticides. The effect of nearby traffic on indoor VOC levels was not distinguished. While concentrations in the Detroit homes were lower than levels found in other North American studies, many homes had elevated VOC levels, including compounds that are known health hazards. Thus, the identification and control of VOC sources is important and prudent, especially for vulnerable individuals. Actions and policies to reduce VOC exposures, e.g., sales restrictions, improved product labeling and consumer education, are recommended. PMID:24329990

Evaluating measurements of carbon dioxide emissions using a precision source--A natural gas burner.

PubMed

Bryant, Rodney; Bundy, Matthew; Zong, Ruowen

2015-07-01

A natural gas burner has been used as a precise and accurate source for generating large quantities of carbon dioxide (CO2) to evaluate emissions measurements at near-industrial scale. Two methods for determining carbon dioxide emissions from stationary sources are considered here: predicting emissions based on fuel consumption measurements-predicted emissions measurements, and direct measurement of emissions quantities in the flue gas-direct emissions measurements. Uncertainty for the predicted emissions measurement was estimated at less than 1%. Uncertainty estimates for the direct emissions measurement of carbon dioxide were on the order of ±4%. The relative difference between the direct emissions measurements and the predicted emissions measurements was within the range of the measurement uncertainty, therefore demonstrating good agreement. The study demonstrates how independent methods are used to validate source emissions measurements, while also demonstrating how a fire research facility can be used as a precision test-bed to evaluate and improve carbon dioxide emissions measurements from stationary sources. Fossil-fuel-consuming stationary sources such as electric power plants and industrial facilities account for more than half of the CO2 emissions in the United States. Therefore, accurate emissions measurements from these sources are critical for evaluating efforts to reduce greenhouse gas emissions. This study demonstrates how a surrogate for a stationary source, a fire research facility, can be used to evaluate the accuracy of measurements of CO2 emissions.

The nature of radio emission from distant galaxies

NASA Astrophysics Data System (ADS)

Richards, Eric A.

I describe an observational program aimed at understanding the radio emission from distant, rapidly evolving galaxy populations. These observations were carried out at 1.4 and 8.5 GHz with the VLA centered on the Hubble Deep Field. Further MERLIN observations of the HDF region at 1.4 GHz provided an angular resolution of 0.2'' and when combined with the VLA data produced an image with an unprecedented rms noise of 4 μJy. All radio sources detected in the VLA complete sample are resolved with a median angular size of 1-2''. The differential count of the radio sources is marginally sub-Euclidean (γ = -2.4 +/- 0.1) and fluctuation analysis suggests nearly 60 sources per armin2 are present at the 1 μJy level. A correlation analysis indicates spatial clustering among the 371 radio sources on angular scales of 1-40 arcmin. Optical identifications are made primarily with bright (I = 22) disk systems composed of irregulars, peculiars, interacting/merging galaxies, and a few isolated field spirals. Available redshifts span the range 0.2-3. These clues coupled with the steep spectral index of the 1.4 GHz selected sample are indicative of diffuse synchrotron radiation in distant galactic disks. Thus the evolution in the microjansky radio population is driven principally by star-formation. I have isolated a number of optically faint radio sources (about 25% of the overall sample) which remain unidentified to I = 26-28 in the HDF and flanking optical fields. Several of these objects have extremely red counterparts and constitute a new class of radio sources which are candidate high redshift dusty protogalaxies.

Gamma-Ray Emision from the Broad-Line Radio Galaxy 3C 111

NASA Technical Reports Server (NTRS)

Hartman, Robert C.; Kadler, Matthias; Tueller, Jack

2008-01-01

The broad-line radio galaxy 3C 111 has been suggested as the counterpart of the Gamma-ray source 3EGJ0416+3650. While 3C 111 meets most of the criteria for a high-probability identification, like a bright fla t-spectrum radio core and a blazarlike broadband SED, in the Third EG RET Catalog, the large positional offset of about 1.5 degrees put 3C1 11 outside the 99% probability region for 3EG J0416+3650, making this association questionable. We present a re-analysis of all available data for 3C111 from the EGRET archives, resulting in probable detection of high-energy Gamma-ray emission above 1000MeV from a position clo se to the nominal position of 3C 111, in two separate viewing periods (VPs), at a 3sigma level in each. A new source, GROJ0426+3747, appea rs to be present nearby, seen only in the >1000MeV data. For >100MeV, the data are in agreement with only one source (at the original cata log position) accounting for most of the EGRET-detected emission of 3 EGJ0416+3650. A follow-up Swift UVOT/XRT observation reveals one mode rately bright X-ray source in the error box of 3EGJ0416+3650, but bec ause of the large EGRET position uncertainty, it is not certain that the X-ray and Gamma-ray sources are associated. A Swift observation of GROJ0426+3747 detected no X.ray source nearby.

Advances in Methane Isotope Measurements via Direct Absorption Spectroscopy with Applications to Oil and Gas Source Characterization

NASA Astrophysics Data System (ADS)

Yacovitch, T. I.; Herndon, S. C.; Roscioli, J. R.; Petron, G.; Shorter, J. H.; Jervis, D.; McManus, J. B.; Nelson, D. D.; Zahniser, M. S.; Kolb, C. E., Jr.

2015-12-01

Instrumental developments in the measurement of multiple isotopes of methane (12CH4, 13CH4 and 12CH3D) are presented. A first generation 8-micron instrument quantifies 12CH4 and 13CH4 at a 1-second rate via tunable infrared direct absorption spectroscopy (TILDAS). A second generation instrument uses two 3-micron intraband cascade lasers in an Aerodyne dual laser chassis for simultaneous measurement of 12CH4, 13CH4 and 12CH3D. Sensitivity and noise performance improvements are examined. The isotopic signature of methane provides valuable information for emission source identification of this greenhouse gas. A first generation spectrometer has been deployed in the field on a mobile laboratory along with a sophisticated 4-tank calibration system. Calibrations are done on an agressive schedule, allowing for the correction of measured isotope ratios to an absolute isotope scale. Distinct isotopic signatures are found for a number of emission sources in the Denver-Julesburg Basin: oil and gas gathering stations, compressor stations and processing plants; a municipal landfill, and dairy/cattle operations. The isotopic signatures are compared with measured ethane/methane ratios. These direct absorption measurements have larger uncertainties than samples measured via gas chromatography-mass spectrometry, but have several advantages over canister sampling methods: individual sources of short duration are easier to isolate; calibrated isotope ratio results are available immediately; replicate measurements on a single source are easily performed; and the number of sources sampled is not limited by canister availability and processing time.

Suzaku and Chandra observations of CIZA J1700.8-3144, a cluster of galaxies in the Zone of Avoidance

NASA Astrophysics Data System (ADS)

Mori, Hideyuki; Maeda, Yoshitomo; Ueda, Yoshihiro; Nakazawa, Kazuhiro; Tawara, Yuzuru

2017-02-01

We present the Chandra and Suzaku observations of 1RXS J170047.8-314442, located towards the Galactic bulge, to reveal a wide-band (0.3-10 keV) X-ray morphology and spectrum of this source. With the Chandra observation, no point source was found at the position of 1RXS J170047.8-314442. Instead, we revealed the presence of diffuse X-ray emission, via the wide-band X-ray image obtained from the Suzaku XIS. Although the X-ray emission had a nearly circular shape with a spatial extent of ˜3{^'.}5, the surface brightness profile was not axisymmetric; a bright spot-like emission was found at ˜ 1' away in the northwestern direction from the center. The radial profile of the surface brightness, except for this spot-like emission, was reproduced with a single β-model; β and the core radius were found to be 1.02 and 1{^'.}51, respectively. The X-ray spectrum of the diffuse emission showed an emission line at ˜6 keV, indicating an origin of a thermal plasma. The spectrum was well explained with an absorbed, optically-thin thermal plasma model with a temperature of 6.2 keV and a redshift parameter of z = 0.14 ± 0.01. Hence, the X-ray emission was considered to arise from the hot gas associated with a cluster of galaxies. Our spectroscopic result confirmed the optical identification of 1RXS J170047.8-314442 by Kocevski et al. (2007, ApJ, 662, 224): CIZA J1700.8-3144, a member of the cluster catalogue in the Zone of Avoidance. The estimated bolometric X-ray luminosity of 5.9 × 1044 erg s-1 was among the lowest with this temperature, suggesting that this cluster is far from relaxed.

Searching for Correlated Radio Transients & Gravitational Wave Bursts

NASA Astrophysics Data System (ADS)

Kavic, Michael; Shawhan, P. S.; Yancey, C.; Cutchin, S.; Simonetti, J. H.; Bear, B.; Tsai, J.

2013-01-01

We will discuss an ongoing multi-messenger search for transient radio pulses and gravitational wave bursts. This work is being conducted jointly by the Long Wavelength Array (LWA) and the LIGO Scientific Collaboration (LSC). A variety of astrophysical sources can produce simultaneous emission of gravitational waves and coherent low-frequency electromagnetic radiation. The primary common source motivating this work is the merger of neutron star binaries for which the LWA and LSC instruments have comparable sensitivity. Additional common sources include supernovae, long timescale GRBs and cosmic string cusp events. Data taken by both instruments can be compared to search for correlated signals. Identification of correlated signals can be used to increase the sensitivity of both instruments. We will summarize the coincident observations which have already been conducted and outline plans for future work. We will describe the process being used for synthesizing these data set and present preliminary results.

Mars Spark Source Prototype

NASA Technical Reports Server (NTRS)

Eichenberg, Dennis J.; Lindamood, Glenn R.; Weiland, Karen J.; VanderWal, Randall L.

1999-01-01

The Mars Spark Source Prototype (MSSP) hardware has been developed as part of a proof of concept system for the detection of trace metals such as lead, cadmium, and arsenic in Martian dusts and soils. A spark discharge produces plasma from a soil sample and detectors measure the optical emission from metals in the plasma that will allow their identification and quantification. Trace metal measurements are vital for the assessment of the potential toxicity of the Martian environment for human exploration. The current method of X-ray fluorescence can yield concentrations only of major species. Other instruments are incompatible with the volume, weight, and power constraints for a Mars mission. The instrument will be developed primarily for use in the Martian environment, but would be adaptable for terrestrial use in environmental monitoring. This paper describes the Mars Spark Source Prototype hardware, the results of the characterization tests, and future plans for hardware development.

Fine particulate matter emissions inventories: comparisons of emissions estimates with observations from recent field programs.

PubMed

Simon, Heather; Allen, David T; Wittig, Ann E

2008-02-01

Emissions inventories of fine particulate matter (PM2.5) were compared with estimates of emissions based on data emerging from U.S. Environment Protection Agency Particulate Matter Supersites and other field programs. Six source categories for PM2.5 emissions were reviewed: on-road mobile sources, nonroad mobile sources, cooking, biomass combustion, fugitive dust, and stationary sources. Ammonia emissions from all of the source categories were also examined. Regional emissions inventories of PM in the exhaust from on-road and nonroad sources were generally consistent with ambient observations, though uncertainties in some emission factors were twice as large as the emission factors. In contrast, emissions inventories of road dust were up to an order of magnitude larger than ambient observations, and estimated brake wear and tire dust emissions were half as large as ambient observations in urban areas. Although comprehensive nationwide emissions inventories of PM2.5 from cooking sources and biomass burning are not yet available, observational data in urban areas suggest that cooking sources account for approximately 5-20% of total primary emissions (excluding dust), and biomass burning sources are highly dependent on region. Finally, relatively few observational data were available to assess the accuracy of emission estimates for stationary sources. Overall, the uncertainties in primary emissions for PM2.s are substantial. Similar uncertainties exist for ammonia emissions. Because of these uncertainties, the design of PM2.5 control strategies should be based on inventories that have been refined by a combination of bottom-up and top-down methods.

Import, use, and emissions of PCBs in Switzerland from 1930 to 2100

PubMed Central

Steinlin, Christine; Schalles, Simone; Wegmann, Lukas; Tremp, Josef; Breivik, Knut; Hungerbühler, Konrad; Bogdal, Christian

2017-01-01

Polychlorinated biphenyls (PCBs) are persistent organic compounds that are ubiquitously found in the environment. Their use and manufacture were restricted or banned in many countries in the 1970–1980s, however, they still persist in the antroposphere, the environment and in biota worldwide today. Conventions like the Convention on Long-range Transboundary Air Pollution encourage or bind the member parties to annually submit emission inventories of regulated air pollutants. Unfortunately, several member states have not yet reported PCB emissions. The identification and quantification of stocks and emissions sources is, however, an important precondition to handle and remove the remaining reservoirs of PCBs and, thus, to be able to reduce emissions and subsequently environmental exposure. Here, we estimate past, present, and future emissions of PCBs to air in Switzerland and provide emission factors for all relevant emission categories. Switzerland hereby represents a typical developed industrial country, and most of the assumptions and parameters presented here can be used to calculate PCB emission also for other countries. PCB emissions to air are calculated using a dynamic mass flow and emissions model for Switzerland, which is run for the years 1930–2100. The results point out the importance of the use of PCBs in open applications, which have largely been previously overlooked. Additionally, we show that PCBs will persist in applications during the coming decades with ongoing emissions. Especially the use of PCBs in open applications will cause Swiss emissions to remain above 100 kg PCB per year, even after the year 2030. Our developed model is available in Excel/VBA and can be downloaded with this article. PMID:28981534

The first Extreme Ultraviolet Explorer source catalog

NASA Technical Reports Server (NTRS)

Bowyer, S.; Lieu, R.; Lampton, M.; Lewis, J.; Wu, X.; Drake, J. J.; Malina, R. F.

1994-01-01

The Extreme Ultraviolet Explorer (EUVE) has conducted an all-sky survey to locate and identify point sources of emission in four extreme ultraviolet wavelength bands centered at approximately 100, 200, 400, and 600 A. A companion deep survey of a strip along half the ecliptic plane was simultaneously conducted. In this catalog we report the sources found in these surveys using rigorously defined criteria uniformly applied to the data set. These are the first surveys to be made in the three longer wavelength bands, and a substantial number of sources were detected in these bands. We present a number of statistical diagnostics of the surveys, including their source counts, their sensitivites, and their positional error distributions. We provide a separate list of those sources reported in the EUVE Bright Source List which did not meet our criteria for inclusion in our primary list. We also provide improved count rate and position estimates for a majority of these sources based on the improved methodology used in this paper. In total, this catalog lists a total of 410 point sources, of which 372 have plausible optical ultraviolet, or X-ray identifications, which are also listed.

Classification of X-ray sources in the direction of M31

NASA Astrophysics Data System (ADS)

Vasilopoulos, G.; Hatzidimitriou, D.; Pietsch, W.

2012-01-01

M31 is our nearest spiral galaxy, at a distance of 780 kpc. Identification of X-ray sources in nearby galaxies is important for interpreting the properties of more distant ones, mainly because we can classify nearby sources using both X-ray and optical data, while more distant ones via X-rays alone. The XMM-Newton Large Project for M31 has produced an abundant sample of about 1900 X-ray sources in the direction of M31. Most of them remain elusive, giving us little signs of their origin. Our goal is to classify these sources using criteria based on properties of already identified ones. In particular we construct candidate lists of high mass X-ray binaries, low mass X-ray binaries, X-ray binaries correlated with globular clusters and AGN based on their X-ray emission and the properties of their optical counterparts, if any. Our main methodology consists of identifying particular loci of X-ray sources on X-ray hardness ratio diagrams and the color magnitude diagrams of their optical counterparts. Finally, we examined the X-ray luminosity function of the X-ray binaries populations.

Disentangling the major source areas for an intense aerosol advection in the Central Mediterranean on the basis of Potential Source Contribution Function modeling of chemical and size distribution measurements

NASA Astrophysics Data System (ADS)

Petroselli, Chiara; Crocchianti, Stefano; Moroni, Beatrice; Castellini, Silvia; Selvaggi, Roberta; Nava, Silvia; Calzolai, Giulia; Lucarelli, Franco; Cappelletti, David

2018-05-01

In this paper, we combined a Potential Source Contribution Function (PSCF) analysis of daily chemical aerosol composition data with hourly aerosol size distributions with the aim to disentangle the major source areas during a complex and fast modulating advection event impacting on Central Italy in 2013. Chemical data include an ample set of metals obtained by Proton Induced X-ray Emission (PIXE), main soluble ions from ionic chromatography and elemental and organic carbon (EC, OC) obtained by thermo-optical measurements. Size distributions have been recorded with an optical particle counter for eight calibrated size classes in the 0.27-10 μm range. We demonstrated the usefulness of the approach by the positive identification of two very different source areas impacting during the transport event. In particular, biomass burning from Eastern Europe and desert dust from Sahara sources have been discriminated based on both chemistry and size distribution time evolution. Hourly BT provided the best results in comparison to 6 h or 24 h based calculations.

Evidence for an extensive intracluster medium from radio observations of distant Abell clusters

NASA Technical Reports Server (NTRS)

Hanisch, R. J.; Ulmer, M. P.

1985-01-01

Observations have been made of 18 distance class 5 and 6 Abell clusters of galaxies using the VLA in its 'C' configuration at a frequency of 1460 MHz. Half of the clusters in the sample are confirmed or probable sources of X-ray emission. All the detected radio sources with flux densities above 10 mJy are reported, and information is provided concerning the angular extent of the sources, as well as the most likely optical identification. The existence of an extensive intracluster medium is inferred by identifying extended/distorted radio sources with galaxies whose apparent magnitudes are consistent with their being cluster members and that are at projected distances of 3-4 Abell radii (6-8 Mpc) from the nearest cluster center. By requiring that the radio sources are confined by the ambient medium, the ambient density is calculated and the total cluster mass is estimated. As a sample calculation, a wide-angle-tail radio source some 5 Mpc from the center of Abell 348 is used to estimate these quantities.

2011 Radioactive Materials Usage Survey for Unmonitored Point Sources

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

Sturgeon, Richard W.

This report provides the results of the 2011 Radioactive Materials Usage Survey for Unmonitored Point Sources (RMUS), which was updated by the Environmental Protection (ENV) Division's Environmental Stewardship (ES) at Los Alamos National Laboratory (LANL). ES classifies LANL emission sources into one of four Tiers, based on the potential effective dose equivalent (PEDE) calculated for each point source. Detailed descriptions of these tiers are provided in Section 3. The usage survey is conducted annually; in odd-numbered years the survey addresses all monitored and unmonitored point sources and in even-numbered years it addresses all Tier III and various selected other sources.more » This graded approach was designed to ensure that the appropriate emphasis is placed on point sources that have higher potential emissions to the environment. For calendar year (CY) 2011, ES has divided the usage survey into two distinct reports, one covering the monitored point sources (to be completed later this year) and this report covering all unmonitored point sources. This usage survey includes the following release points: (1) all unmonitored sources identified in the 2010 usage survey, (2) any new release points identified through the new project review (NPR) process, and (3) other release points as designated by the Rad-NESHAP Team Leader. Data for all unmonitored point sources at LANL is stored in the survey files at ES. LANL uses this survey data to help demonstrate compliance with Clean Air Act radioactive air emissions regulations (40 CFR 61, Subpart H). The remainder of this introduction provides a brief description of the information contained in each section. Section 2 of this report describes the methods that were employed for gathering usage survey data and for calculating usage, emissions, and dose for these point sources. It also references the appropriate ES procedures for further information. Section 3 describes the RMUS and explains how the survey results are organized. The RMUS Interview Form with the attached RMUS Process Form(s) provides the radioactive materials survey data by technical area (TA) and building number. The survey data for each release point includes information such as: exhaust stack identification number, room number, radioactive material source type (i.e., potential source or future potential source of air emissions), radionuclide, usage (in curies) and usage basis, physical state (gas, liquid, particulate, solid, or custom), release fraction (from Appendix D to 40 CFR 61, Subpart H), and process descriptions. In addition, the interview form also calculates emissions (in curies), lists mrem/Ci factors, calculates PEDEs, and states the location of the critical receptor for that release point. [The critical receptor is the maximum exposed off-site member of the public, specific to each individual facility.] Each of these data fields is described in this section. The Tier classification of release points, which was first introduced with the 1999 usage survey, is also described in detail in this section. Section 4 includes a brief discussion of the dose estimate methodology, and includes a discussion of several release points of particular interest in the CY 2011 usage survey report. It also includes a table of the calculated PEDEs for each release point at its critical receptor. Section 5 describes ES's approach to Quality Assurance (QA) for the usage survey. Satisfactory completion of the survey requires that team members responsible for Rad-NESHAP (National Emissions Standard for Hazardous Air Pollutants) compliance accurately collect and process several types of information, including radioactive materials usage data, process information, and supporting information. They must also perform and document the QA reviews outlined in Section 5.2.6 (Process Verification and Peer Review) of ES-RN, 'Quality Assurance Project Plan for the Rad-NESHAP Compliance Project' to verify that all information is complete and correct.« less

Generation Mechanisms UV and X-ray Emissions During SL9 Impact

NASA Technical Reports Server (NTRS)

Waite, J. Hunter, Jr.

1997-01-01

The purpose of this grant was to study the ultraviolet and X-ray emissions associated with the impact of comet Shoemaker-Levy 9 with Jupiter. The University of Michigan task was primarily focused on theoretical calculations. The NAGW-4788 subtask was to be largely devoted to determining the constraints placed by the X-ray observations on the physical mechanisms responsible for the generation of the X-rays. Author summarized below the ROSAT observations and suggest a physical mechanism that can plausibly account for the observed emissions. It is hoped that the full set of activities can be completed at a later date. Further analysis of the ROSAT data acquired at the time of the impact was necessary to define the observational constraints on the magnetospheric-ionospheric processes involved in the excitation of the X-ray emissions associated with the fragment impacts. This analysis centered around improvements in the pointing accuracy and improvements in the timing information. Additional pointing information was made possible by the identification of the optical counterparts to the X-ray sources in the ROSAT field-of-view. Due to the large number of worldwide observers of the impacts, a serendipitous visible plate image from an observer in Venezuela provided a very accurate location of the present position of the X-ray source, virtually eliminating pointing errors in the data. Once refined, the pointing indicated that the two observed X-ray brightenings that were highly correlated in time with the K and P2 events were brightenings of the X-ray aurora (as identified in images prior to the impact).Appendix A "ROSAT observations of X-ray emissions from Jupiter during the impact of comet Shoemaker-Levy 9' also included.

A Global Catalogue of Large SO2 Sources and Emissions Derived from the Ozone Monitoring Instrument

NASA Technical Reports Server (NTRS)

Fioletov, Vitali E.; McLinden, Chris A.; Krotkov, Nickolay; Li, Can; Joiner, Joanna; Theys, Nicolas; Carn, Simon; Moran, Mike D.

2016-01-01

Sulfur dioxide (SO2) measurements from the Ozone Monitoring Instrument (OMI) satellite sensor processed with the new principal component analysis (PCA) algorithm were used to detect large point emission sources or clusters of sources. The total of 491 continuously emitting point sources releasing from about 30 kt yr(exp -1) to more than 4000 kt yr(exp -1) of SO2 per year have been identified and grouped by country and by primary source origin: volcanoes (76 sources); power plants (297); smelters (53); and sources related to the oil and gas industry (65). The sources were identified using different methods, including through OMI measurements themselves applied to a new emission detection algorithm, and their evolution during the 2005- 2014 period was traced by estimating annual emissions from each source. For volcanic sources, the study focused on continuous degassing, and emissions from explosive eruptions were excluded. Emissions from degassing volcanic sources were measured, many for the first time, and collectively they account for about 30% of total SO2 emissions estimated from OMI measurements, but that fraction has increased in recent years given that cumulative global emissions from power plants and smelters are declining while emissions from oil and gas industry remained nearly constant. Anthropogenic emissions from the USA declined by 80% over the 2005-2014 period as did emissions from western and central Europe, whereas emissions from India nearly doubled, and emissions from other large SO2-emitting regions (South Africa, Russia, Mexico, and the Middle East) remained fairly constant. In total, OMI-based estimates account for about a half of total reported anthropogenic SO2 emissions; the remaining half is likely related to sources emitting less than 30 kt yr(exp -1) and not detected by OMI.

Determining the source region of auroral emissions in the prenoon oval using coordinated Polar BEAR UV-imaging and DMSP particle measurements

NASA Technical Reports Server (NTRS)

Newell, Patrick T.; Meng, CHING-I.; Huffman, Robert E.

1992-01-01

The Polar Beacon Experiment and Auroral Research (Polar BEAR) satellite included the capability for imaging the dayside auroral oval in full sunlight at several wavelengths. Particle observations from the DMSP F7 satellite during dayside auroral oval crossings are compared with approximately simultaneous Polar BEAR 1356-A images to determine the magnetospheric source region of the dayside auroral oval. The source region is determined from the DMSP particle data, according to recent work concerning the classification and identification of precipitation source regions. The close DMSP/Polar BEAR coincidences all occur when the former satellite is located between 0945 and 1000 MLT. Instances of auroral arcs mapping to each of several different regions, including the boundary plasma sheet, the low-latitude boundary layer, and the plasma mantle were found. It was determined that about half the time the most prominent auroral arcs are located at the interfaces between distinct plasma regions, at least at the local time studied here.

Radio Sources Associated with Intermediate X-ray Luminosity Objects in Merging Galaxy Systems

NASA Technical Reports Server (NTRS)

Neff, S. G.; Ulvestad, J. S.; Oegerle, William R. (Technical Monitor)

2002-01-01

We present new, high-resolution 6, 3.6, and 2 cm radio images of a time-ordered sequence of merging galaxy systems. The new data have a resolution of less than 100pc and a sensitivity comparable to a few x Cas A. We detect compact radio sources in all systems, generally embedded in more diffuse radio emission at the longer wavelengths. Several of the compact radio sources are coincident with compact Intermediate-luminosity X-ray Objects (IXOs) in these systems, and many more are within the 3$/sigma$ Chandra position errors for other IXOs. The fraction of radio identifications and the nature of the radio sources changes as a function of merger stage. These data suggest that the IXOs are associated with complexes of supernova remnants, and therefore with star formation that has occurred within the last $/sim$10$circumflex7$ yr, but are not located in HII regions where copious star formation is occurring currently.

A novel monodisperse SiO2@C-dot for the rapid and facile identification of latent fingermarks using self-quenching resistant solid-state fluorescence.

PubMed

Peng, Di; Liu, Xiang; Huang, Mengjun; Wang, Dan; Liu, Renlong

2018-04-24

Solid powder fluorescence shows great potential for application in medicine, biology, and engineering, especially in the identification of latent fingermarks in forensic science. However, conventional developing methods suffer from some drawbacks, such as low contrast, low sensitivity, low selectivity, and high toxicity. To conquer these challenges, novel SiO2@C-dot microspheres were prepared via a facile one-pot hydrothermal method by using citric acid as a carbon source and aminosilane as a nitrogen source. Interestingly, the results showed that the resultant powders possess good monodispersity, high fluorescence emission, and resistance to self-quenching. Additionally, the mechanism for the solid-state fluorescence of SiO2@C-dot compounds was also investigated. More importantly, the fingermarks on various surfaces, including transparent glasses, ceramic tiles, transparent plastics, aluminum alloys, plastic cards, painted woods, artificial leathers, and Chinese paper money, developed by the powders have indicated well-defined papillary ridges under a 365 nm UV lamp. The novel strategy of using monodisperse SiO2@C-dot microspheres as a fluorescent label for developing latent fingermarks showed greater advantages compared to conventional methods, which was also demonstrated using the automatic fingerprint identification system. It is simple, rapid, low-cost, nontoxic, and effective, and is expected to be a promising alternative for the development of latent fingerprints in forensic science.

Multiwavelength observations of unidentified high energy gamma ray sources

NASA Technical Reports Server (NTRS)

Halpern, Jules P.

1993-01-01

As was the case for COS B, the majority of high-energy (greater than 100 MeV) gamma-ray sources detected by the EGRET instrument on GRO are not immediately identifiable with cataloged objects at other wavelengths. These persistent gamma-ray sources are, next to the gamma-ray bursts, the least understood objects in the universe. Even a rudimentary understanding of their nature awaits identifications and follow-up work at other wavelengths to tell us what they are. The as yet unidentified sources are potentially the most interesting, since they may represent unrecognized new classes of astronomical objects, such as radio-quiet pulsars or new types of active galactic nuclei (AGN's). This two-year investigation is intended to support the analysis, correlation, and theoretical interpretation of data that we are obtaining at x ray, optical, and radio wavelengths in order to render the gamma-ray data interpretable. According to plan, in the first year concentration was on the identification and study of Geminga. The second year will be devoted to studies of similar unidentified gamma-ray sources which will become available in the first EGRET catalogs. The results obtained so far are presented in the two papers which are reproduced in the Appendix. In these papers, we discuss the pulse profiles of Geminga, the geometry and efficiency of the magnetospheric accelerator, the distance to Geminga, the implications for theories of polar cap heating, the effect of the magnetic field on the surface emission and environment of the neutron star, and possible interpretations of a radio-quiet Geminga. The implications of the other gamma-ray pulsars which were discovered to have high gamma-ray efficiency are also discussed, and the remaining unidentified COS B sources are attributed to a population of efficient gamma-ray sources, some of which may be radio quiet.

Constraining CO emission estimates using atmospheric observations

NASA Astrophysics Data System (ADS)

Hooghiemstra, P. B.

2012-06-01

We apply a four-dimensional variational (4D-Var) data assimilation system to optimize carbon monoxide (CO) emissions and to reduce the uncertainty of emission estimates from individual sources using the chemistry transport model TM5. In the first study only a limited amount of surface network observations from the National Oceanic and Atmospheric Administration Earth System Research Laboratory (NOAA/ESRL) Global Monitoring Division (GMD) is used to test the 4D-Var system. Uncertainty reduction up to 60% in yearly emissions is observed over well-constrained regions and the inferred emissions compare well with recent studies for 2004. However, since the observations only constrain total CO emissions, the 4D-Var system has difficulties separating anthropogenic and biogenic sources in particular. The inferred emissions are validated with NOAA aircraft data over North America and the agreement is significantly improved from the prior to posterior simulation. Validation with the Measurements Of Pollution In The Troposphere (MOPITT) instrument shows a slight improved agreement over the well-constrained Northern Hemisphere and in the tropics (except for the African continent). However, the model simulation with posterior emissions underestimates MOPITT CO total columns on the remote Southern Hemisphere (SH) by about 10%. This is caused by a reduction in SH CO sources mainly due to surface stations on the high southern latitudes. In the second study, we compare two global inversions to estimate carbon monoxide (CO) emissions for 2004. Either surface flask observations from NOAA or CO total columns from the MOPITT instrument are assimilated in a 4D-Var framework. In the Southern Hemisphere (SH) three important findings are reported. First, due to their different vertical sensitivity, the stations-only inversion increases SH biomass burning emissions by 108 Tg CO/yr more than the MOPITT-only inversion. Conversely, the MOPITT-only inversion results in SH natural emissions (mainly CO from oxidation of NMVOCs) that are 185 Tg CO/yr higher compared to the stations-only inversion. Second, MOPITT-only derived biomass burning emissions are reduced with respect to the prior which is in contrast to previous (inverse) modeling studies. Finally, MOPITT derived total emissions are significantly higher for South America and Africa compared to the stations-only inversion. This is likely due to a positive bias in the MOPITT V4 product. This bias is also apparent from validation with surface stations and ground-truth FTIR columns. In the final study we present the first inverse modeling study to estimate CO emissions constrained by both surface (NOAA) and satellite (MOPITT) observations using a bias correction scheme. This approach leads to the identification of a positive bias of maximum 5 ppb in MOPITT column-averaged CO mixing ratios in the remote Southern Hemisphere (SH). The 4D-Var system is used to estimate CO emissions over South America in the period 2006-2010 and to analyze the interannual variability (IAV) of these emissions. We infer robust, high spatial resolution CO emission estimates that show slightly smaller IAV due to fires compared to the Global Fire Emissions Database (GFED3) prior emissions. Moreover, CO emissions probably associated with pre-harvest burning of sugar cane plantations are underestimated in current inventories by 50-100%.

Emission inventory of primary air pollutants in 2010 from industrial processes in Turkey.

PubMed

Alyuz, Ummugulsum; Alp, Kadir

2014-08-01

The broad objective of this study was to develop CO2, PM, SOx, CO, NOx, VOC, NH3 and N2O emission inventory of organic and inorganic chemicals, mineral products, metallurgical, petroleum refining, wood products, food industries of Turkey for 2010 for both co]ntrolled and uncontrolled conditions. In this study, industries were investigated in 7 main categories and 53 sub-sectors and a representative number of pollutants per sub-sector were considered. Each industry was evaluated in terms of emitted emissions only from industrial processes, and fuel combustion activities were excluded (except cement industry). The study employed an approach designed in four stages; identification of key categories; activity data & emission factor search; emission factor analyzing; calculation of emissions. Emission factor analyzing required aggregate and firm analysis of sectors and sub-sectors and deeper insights into underlying specific production methods used in the industry to decide on the most representative emission factor. Industry specific abatement technologies were considered by using open-source documents and industry specific reports. Regarding results of this study, mineral industry and iron & steel industry were determined as important contributors of industrial emissions in Turkey in 2010. Respectively, organic chemicals, petroleum refining, and pulp & paper industries had serious contributions to Turkey's air pollutant emission inventory from industrial processes. The results showed that calculated CO2 emissions for year 2010 was 55,124,263 t, also other emissions were 48,853 t PM, 24,533 t SOx, 79,943 t NOx, 31,908 t VOC, 454 t NH3 and 2264 t N2O under controlled conditions. Copyright © 2014 Elsevier B.V. All rights reserved.

Establishing aeolian particulate 'fingerprints' in an airport environment using magnetic measurements and SEM/EDAX

NASA Astrophysics Data System (ADS)

Jones, Sue; Hoon, Stephen R.; Richardson, Nigel; Bennett, Michael

2016-04-01

The significant increase in global air travel which has occurred during the last fifty years has generated growing concern regarding the potential impacts associated with increasing emissions of particulate matter (PM) from aviation activity on health and the environment. PM within the airport environment, in particular, may be derived from a wide range of potential sources including aircraft; vehicles; ground support equipment and buildings. In order to investigate and remediate potential problem sources, it is important to be able to identify characteristic particulate 'fingerprints' which would allow source attribution, particularly respirable particulates. To date the identification of such 'fingerprints' has remained elusive but remains a key research priority for the aviation industry (Webb et al, 2008). In previous PM studies, environmental magnetism has been used as a successful technique for discriminating between different emission types and particulate sources in both urban and industrial environments (e.g. Hunt et al 1984; Lecoanet et al 2003, Jones et al 2015). Environmental magnetism is a non-destructive and relatively rapid technique involving the use of non-directional, rock magnetic measurements to characterise the mineral magnetic properties of natural and anthropogenic materials. In other studies scanning electron microscopy (SEM) has also been used as an effective characterisation technique for the investigation of grain size and morphology of PM derived from vehicle emissions (e.g. Bucko et al 2010) and fossil fuel combustion sources (Kim et al 2009). In this study, environmental magnetic measurements and SEM/EDAX have been used to characterise dusts from specific aircraft sources including engines, brakes and tyres. Furthermore, these methods have also been applied to runway (both hard and grass covered surfaces), taxiway and apron dusts collected during extensive environmental sampling at Manchester International Airport, UK in order to investigate source attribution. The results indicate that the dusts collected from the various aircraft sources (i.e. engines, brakes and tyres) are significantly different in terms of magnetic mineral type and grain size. Furthermore, particulates deposited at different locations on the runway surface show significant differentiation in magnetic grain size and mineralogy which when compared with the results from the different aircraft sources suggest that they may relate to emissions from different sources at various stages of the take/off landing cycle. Results of SEM/EDAX analysis show that aircraft engine, brake and tyre dust particulates vary significantly in terms of morphology and chemical composition. All sources include respirable (sub 10 micron) particulates. Engine dusts are carbon and silicon rich dominated by angular particulates. They have a distinctive chemical composition including Chromium, Cobalt and Nickel. Tyre dusts are predominantly carbon based dominated by spherical particulates and a unique presence of Zinc. Brake dusts, carbon and oxygen dominated and trace metals, include sub-angular particulates but an absence of the characteristic engine and tyre dusts metals. By combining SEM/EDAX measurements and magnetic measurements we are establishing potential fingerprints for particulates from ground based air transport activities to enable identification of potential health hazards. This will help inform management plans for reduction of associated risks to the environment and health. References Bucko, M., Magiera, T., Pesonen, L., Janus, B. (2010) 'Magnetic, geochemical and microstructural characteristics of road dust on roadsides with different traffic volumes - Case study from Finland' Water, Air and Soil Pollution 209, pp. 295-306. Hunt, A., Jones, J. and Oldfield, F. (1984) 'Magnetic measurements and heavy metals in atmospheric particulates of anthropogenic origin' The Science of the Total Environment 33, 129-139. Jones, S., Richardson, N., Bennett, M. and Hoon, S.R. (2015) The application of magnetic measurements for the characterization of atmospheric particulate pollution within the airport environment. Science of the Total Environment., 502 pp.385-390 Kim, W., Doh, S., Yu, Y. (2009) 'Anthropogenic contribution of magnetic particulates in urban roadside dust' Atmospheric Environment 43 (19) pp.3137-3144. Lecoanet, H., Leveque, F. and Ambrosi, J.P. (2003) 'Combination of magnetic parameters: an efficient way to discriminate soil-contamination sources (south France)' Environmental Pollution 122, 229-234. Webb, S., Whitefield, P.D., Miake-Lye, R.C., Timko, M.T. and Thrasher, T.G. (2008) 'ACRP Report 6: Research needs associated with particulate emissions at airports'. Transportation Research Board'.

Emissions of volatile organic compounds during the ship-loading of petroleum products: Dispersion modelling and environmental concerns.

PubMed

Milazzo, Maria Francesca; Ancione, Giuseppa; Lisi, Roberto

2017-12-15

Emissions due to ship-loading of hydrocarbons are currently not addressed neither by the Directive on the integrated pollution prevention or by other environmental regulations. The scope of this study is to point towards the environmental and safety concerns associated with such emissions, even if proper attention has not been given to this issue until now. In order to achieve this goal, the modelling of the emission volatile organic compounds (VOC), due to ship-load operations at refineries has been made by means of the definition of a simulation procedure which includes a proper treatment of the hours of calm. Afterwards, a quantitative analysis of VOC dispersion for an Italian case-study is presented with the primary aims: (i) to develop and verify the validity of the approach for the modelling of the emission sources and of the diffusion of these contaminants into the atmosphere by a proper treatment of the hours of calm and (ii) to identify their contribution to the total VOC emitted in a typical refinery. The calculated iso-concentration contours have also been drawn on a map and allowed the identification of critical areas for people protecting by the adoption of abatement solutions. Copyright © 2017 Elsevier Ltd. All rights reserved.

Sensitivity tests to define the source apportionment performance criteria in the DeltaSA tool

NASA Astrophysics Data System (ADS)

Pernigotti, Denise; Belis, Claudio A.

2017-04-01

Identification and quantification of the contribution of emission sources to a given area is a key task for the design of abatement strategies. Moreover, European member states are obliged to report this kind of information for zones where the pollution levels exceed the limit values. At present, little is known about the performance and uncertainty of the variety of methodologies used for source apportionment and the comparability between the results of studies using different approaches. The source apportionment Delta (SA Delta) is a tool developed by the EC-JRC to support the particulate matter source apportionment modellers in the identification of sources (for factor analysis studies) and/or in the measure of their performance. The source identification is performed by the tool measuring the proximity of any user chemical profile to preloaded repository data (SPECIATE and SPECIEUROPE). The model performances criteria are based on standard statistical indexes calculated by comparing participants' source contribute estimates and their time series with preloaded references data. Those preloaded data refer to previous European SA intercomparison exercises: the first with real world data (22 participants), the second with synthetic data (25 participants) and the last with real world data which was also extended to Chemical Transport Models (38 receptor models and 4 CTMs). The references used for the model performances are 'true' (predefined by JRC) for the synthetic while they are calculated as ensemble average of the participants' results in real world intercomparisons. The candidates used for each source ensemble reference calculation were selected among participants results based on a number of consistency checks plus the similarity between their chemical profiles to the repository measured data. The estimation of the ensemble reference uncertainty is crucial in order to evaluate the users' performances against it. For this reason a sensitivity analysis on different methods to estimate the ensemble references' uncertainties was performed re-analyzing the synthetic intercomparison dataset, the only one where 'true' reference and ensemble reference contributions were both present. The Delta SA is now available on-line and will be presented, with a critical discussion of the sensitivity analysis on the ensemble reference uncertainty. In particular the grade of among participants mutual agreement on the presence of a certain source should be taken into account. Moreover also the importance of the synthetic intercomparisons in order to catch receptor models common biases will be stressed.

IDENTIFICATION OF A POPULATION OF X-RAY-EMITTING MASSIVE STARS IN THE GALACTIC PLANE

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

Anderson, Gemma E.; Gaensler, B. M.; Kaplan, David L.

2011-02-01

We present X-ray, infrared, optical, and radio observations of four previously unidentified Galactic plane X-ray sources: AX J163252-4746, AX J184738-0156, AX J144701-5919, and AX J144547-5931. Detection of each source with the Chandra X-ray Observatory has provided sub-arcsecond localizations, which we use to identify bright infrared counterparts to all four objects. Infrared and optical spectroscopy of these counterparts demonstrate that all four X-ray sources are extremely massive stars, with spectral classifications: Ofpe/WN9 (AX J163252-4746), WN7 (AX J184738-0156 = WR121a), WN7-8h (AX J144701-5919), and OIf{sup +} (AX J144547-5931). AX J163252-4746 and AX J184738-0156 are both luminous, hard, X-ray emitters with strong Femore » XXV emission lines in their X-ray spectra at {approx}6.7 keV. The multi-wavelength properties of AX J163252-4746 and AX J184738-0156 are not consistent with isolated massive stars or accretion onto a compact companion; we conclude that their X-ray emission is most likely generated in a colliding-wind binary (CWB) system. For both AX J144701-5919 and AX J144547-5931, the X-ray emission is an order of magnitude less luminous and with a softer spectrum. These properties are consistent with a CWB interpretation for these two sources also, but other mechanisms for the generation of X-rays cannot be excluded. There are many other as yet unidentified X-ray sources in the Galactic plane, with X-ray properties similar to those seen for AX J163252-4746, AX J184738-0156, AX J144701-5919, and AX J144547-5931. This may indicate a substantial population of X-ray-emitting massive stars and CWBs in the Milky Way.« less

A membrane basis for bacterial identification and discrimination using laser-induced breakdown spectroscopy

NASA Astrophysics Data System (ADS)

Rehse, Steven J.; Jeyasingham, Narmatha; Diedrich, Jonathan; Palchaudhuri, Sunil

2009-05-01

Nanosecond single-pulse laser-induced breakdown spectroscopy (LIBS) has been used to discriminate between two different genera of Gram-negative bacteria and between several strains of the Escherichia coli bacterium based on the relative concentration of trace inorganic elements in the bacteria. Of particular importance in all such studies to date has been the role of divalent cations, specifically Ca2+ and Mg2+, which are present in the membranes of Gram-negative bacteria and act to aggregate the highly polar lipopolysaccharide molecules. We have demonstrated that the source of emission from Ca and Mg atoms observed in LIBS plasmas from bacteria is at least partially located at the outer membrane by intentionally altering membrane biochemistry and correlating these changes with the observed changes in the LIBS spectra. The definitive assignment of some fraction of the LIBS emission to the outer membrane composition establishes a potential serological, or surface-antigen, basis for the laser-based identification. E. coli and Pseudomonas aeruginosa were cultured in three nutrient media: trypticase soy agar as a control, a MacConkey agar with a 0.01% concentration of bile salts including sodium deoxycholate, and a trypticase soy agar with a 0.4% deoxycholate concentration. The higher concentration of deoxycholate is known to disrupt bacterial outer membrane integrity and was expected to induce changes in the observed LIBS spectra. Altered LIBS emission was observed for bacteria cultured in this 0.4% medium and laser ablated in an all-argon environment. These spectra evidenced a reduced calcium emission and in the case of one species, a reduced magnesium emission. Culturing on the lower (0.01%) concentration of bile salts altered the LIBS spectra for both the P. aeruginosa and two strains of E. coli in a highly reproducible way, although not nearly as significantly as culturing in the higher concentration of deoxycholate did. This was possibly due to the accumulation of divalent cations around the bacteria by the formation of an extracellular polysaccharide capsule. Lastly, a discriminant function analysis demonstrated that in spite of alterations in the LIBS spectrum induced by growth in the three different media, the analysis could correctly identify all samples better than 90% of the time. This encouraging result illustrates the potential utility of LIBS as a rapid bacteriological identification technology.