Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 20 of 31 for “"Elemental Carbon"”.
-
The Control of Diesel Particulates in Underground Coal Mines
… b) Seven engines with unacceptable raw exhaust elemental carbon emissions were identified in a fleet of 66 tested. Some faults identified as causing these elevated emission levels were- blocked exhaust flame traps (scrubber tanks), incorrectly set tappets and worn injectors. c) Testing of a …
-
Speciated Local Aerosol Characteristics and Radiative Forcing at a Rural Midwestern Site
… sample sets were used to obtain sulfate, organic carbon (OC), elemental carbon (EC), carbonate and total aerosol mass. The third sample set was used to obtain the size-specific and wavelength-dependent extinction efficiency of EC.
-
Spatial trends in surface-based carbonaceous aerosol measurements during DISCOVER-AQ in Houston, TX.
Carbonaceous aerosol (both fine particulate matter (PM₂.₅) and total suspended particulate (TSP)) were collected during NASA's DISCOVER-AQ (Deriving Information on Surface Conditions from Column and Vertically Resolved Observations Relevant to Air Quality) in Houston, TX during September 2013. Four …
-
Seasonal Pattern and Sources of Particulate Carbon in Kananaskis and Calgary, Alberta
Sources, seasonal pattern of elemental carbon(EC), organic carbon(OC), and total carbon from dry deposition and precipitation in Kananaskis and Calgary were assessed using thermo-optical methods. Vehicle exhaust was inferred to be dominant source of carbon throughout the year with an identical …
-
Characterization and source apportionment of ambient PM2.5 in Atlanta, Georgia: on-road emission, biomass burning and SOA impact
… of GC/MS-quantified organic compounds, organic carbon (OC), water-soluble organic carbon (WSOC), elemental carbon (EC), ionic species, and tens of trace metals. Day-night, seasonal and spatial variations of PM2.5 characterization were also studied. Contributions of PM2.5 major sources were …
-
Biosignature storage in sulfate minerals- synthetic and natural investigations of the jarosite group minerals
… samples were analyzed by x-ray diffraction, elemental carbon analysis and laser-desorption Fourier transform mass spectrometry (LD-FTMS) and were found to contain the amino acid glycine. Synthetic experiments were conducted in which the different end-members were synthesized in the presence …
-
Biosignature storage in sulfate minerals- synthetic and natural investigations of the jarosite group minerals
… samples were analyzed by x-ray diffraction, elemental carbon analysis and laser-desorption Fourier transform mass spectrometry (LD-FTMS) and were found to contain the amino acid glycine. Synthetic experiments were conducted in which the different end-members were synthesized in the presence …
-
Field emission measurements of solid fuel stoves in Yunnan, China
Emission factors of carbon monoxide (CO), particulate matter (PM2.5), organic carbon (OC), and elemental carbon (EC), as well as combustion efficiency and particle optical properties were measured during 37 uncontrolled cooking tests of residential stoves in Yunnan Province, China. Fuel mixtures …
-
The impacts of aviation emissions on human health through changes in air quality and UV irradiance
… matter (PM25) by estimating changes in elemental carbon, primary and secondary organic PM, secondary sulfates, and secondary nitrates. The air quality model discussed herein is the second iteration in the development of a response surface model (RSM) based on a set of 25 simulations done …
-
Particulate Matter Air Monitoring Network in the San Francisco Bay Area: Assessment and Management Recommendations
… mass concentration, ion speciation, organic and elemental carbon composition, and metals speciation for both PM<sub>10</sub> and PM<sub>2.5</sub>. Monthly averages ranging from 2011-2015 of these components were analyzed and used to evaluate whether the Air District was effectively monitoring for …
-
Determination of the Oxidative Capacity of Soot Toward GSH and Characterization of Soot Physicochemical Properties
… R<sup>2</sup> value of 0.708. It is thought that elemental carbon (EC) drives particle toxicity. This research contributes to the analytical determination of particle toxicity and helps increase our understanding of the mechanisms that control their adverse effects.</p>
-
Design, Development, Characterization, and Application of the DRI Model 2015 Multiwavelength Carbon Analyzer
A multiwavelength thermal/optical carbon analyzer (DRI Model 2015) equipped with a novel seven-wavelength light source (405, 445, 532, 635, 780, 808, and 980 nm) was developed to analyze chemical and optical properties of carbonaceous particles collected on quartz-fiber filters. Built upon on the …
-
Characterisation of Microphysical and Optical Properties of Atmospheric Aerosols in a High Arctic environment: Villum Research Station, NE Greenland
… number concentrations were found to be dust, Elemental Carbon/Organic Carbon (EC/OC) and mixed aerosols, with source regions across continental Greenland, the Canadian Archipelago and Arctic Ocean.
-
Real time analysis of atmospheric single particles in urban environments using aerosol time of flight mass spectrometry
… types detected during MEGAPOLI included several carbonaceous species, metal-containing types and sea-salt. Elemental carbon particle types were highly abundant, with 86% due to fossil fuel combustion and 14% attributed to biomass burning. Furthermore, 79% of the EC was apportioned to local …
-
Characterization, Speciation, and Source Apportionment of Particles inside and from the Exhaust of Public Transit Buses Fueled With Alternative Fuels
… a computer controlled SEM to obtain aerosol elemental compositions. Factor analysis suggested possible sources of indoor particle levels in public transit bus as motor vehicles, outdoor soil and secondary particle formation. The conclusion is that SEM methodology is a valuable tool for …
-
Physico-chemical characterisation of atmospheric aerosols in Tanzania, with emphasis on the carbonaceous aerosol components and on chemical mass closure
… unit sampler with sequential Nuclepore polycarbonate filters, providing coarse (2-10 µm diameter) and fine (<2 µm) size fractions, and PM2.5 and PM10 tandem filter samplers with pre-fired quartz fibre filters were deployed. Depending upon the season and the location, either 24-hour …
-
Development of improved sampling and analysis methods for measuring organic, elemental, and water-soluble organic carbon in atmospheric aerosols and application to aerosol studies in Europe and tropical/equatorial and oceanic regions
… for a better discrimination between organic and elemental carbon (OC and EC) using the thermal-optical transmission (TOT) technique; (2) to deploy improved collection procedures for carbonaceous aerosols, whereby the sampling artifacts are better controlled or can be corrected for; (3) to perform …
-
Applications of Thermal and Laser-Based Methods for Monitoring Airborne Particulates in Coal Mines
… coal mine dust is not coal, but rather carbonates and non-carbonate minerals (i.e. silica and silicates). These findings are significant as many researchers now suspect silica and silicates to be the true culprit in the occupational lung disease of coal miners. DPM presents an additional …
-
Emissions from combustion technologies with a focus on brick making and in-home cooking
… including particulate matter (PM 2.5), carbon monoxide (CO), carbonaceous particles, and optical scattering and absorption. In addition, a pilot study was conducted of small-scale industry emissions from a restaurant, candy making operation, and two pottery kilns. Emission factors from …
-
Decadal trends in atmospheric organic aerosol :
… major aerosol species: nitrate, sulfate, and elemental carbon. This suggests a link between the controlling factors of the different species, but explaining these observations is made challenging by the lack of chemical characterization of historic OA measurements that would help point to …
Page 1 of 2