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.
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Showing 1 to 16 of 16 for “"biogenic emissions"”.
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The Search For Volatile Biogenic Emissions In Geothermal Areas
A primary discipline of astrobiology is the search for life outside of the earth’s ecosystem. Detecting biosignatures in outer space is one way this search is conducted. To understand the biosignatures to look for and study in space, it is useful to gain a better understanding of life in diverse …
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The Search For Volatile Biogenic Emissions In Geothermal Areas
A primary discipline of astrobiology is the search for life outside of the earth’s ecosystem. Detecting biosignatures in outer space is one way this search is conducted. To understand the biosignatures to look for and study in space, it is useful to gain a better understanding of life in diverse …
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Modelling Climate Changes, Biogenic Emissions and Tropospheric Chemistry in Southeast Asia.
A regional climate model (PRECIS) and a biogenic emission model (BVOCEM) were used to investigate the impact of climate changes on biogenic emissions during northeast monsoon (Dec-Jan-Feb, DJF) and southwest monsoon (Jun-(July)-Aug, JJA) in both the A2 and B2 transient climate scenarios of the IPCC …
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Projections of Future Changes in Surface Ozone Concentrations Over the United States, Effects of Pollutant Transport, and Uncertainty Analyses
… effects of climate change, resulting changes in biogenic precursor emissions, and changes in anthropogenic precursor emissions within and outside the contiguous U.S. territory. Considering the uncertainties in ozone projections, two cases of potential changes in climate and precursor emissions …
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Summertime ozone pollution in China: Observations and Simulations
… high levels of ozone due to high precursor emissions in association with rapid urbanization and industrialization in past decades. In this fast-changing environment, a better understanding of the ozone formation process, as well as accurate estimations of the ground-level ozone and its …
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Volatile organic compounds in the New England troposphere: Atmospheric chemistry and measurement techniques
… was strongly dependent on reactions of NO3 with biogenic volatile organic compounds and the fate of dinitrogen pentoxide (N 2O5). For three case studies, temporal profiles of NO 3 were calculated from measured parameters. Comparisons between measured and calculated NO3 mixing ratios highlighted …
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MEASUREMENTS OF ATMOSPHERIC RADICALS IN AMBIENT AND INDOOR ENVIRONMENTS: OUTDOOR-INDOOR RELATIONSHIPS, INDOOR FORMATION MECHANISMS, AND INSTRUMENTAL ANALYSIS
… ambient environments with high mixing ratios of biogenic VOCs and low mixing ratios of NOx, measurements using our current instrumental technique for radicals have shown discrepancies with modeled predictions. Here, these discrepancies were investigated during the Indiana Radical, Reactivity, and …
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Simulating the sources of organic aerosol in the atmosphere
… has the ability to determine the sources of the emissions of the OA as well as how many generations of oxidation reactions OA has undergone. This algorithm was used in parallel with a chemical transport model for the first time in Europe. The results showed that the sources of OA can vary …
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Synoptic controls on ozone over the northeastern US and continental export
… to non-linear relationships between climate and biogenic emissions and decreasing power plant emissions over the analysis period. Second, during spring continental export was evident from enhanced O3 (>55 ppbv) and CO (>115 ppbv) at the 681 hPa retrieval level suggesting anthropogenic influence. …
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Ozone Precursor Sources and Box Modeling of Ozone in Mexico City Under Altered Emission Conditions
… abundance, linked to industrial and vehicular emissions. In the second task, a modified positive matrix factorization (PMF) with Fpeak rotation (0.3 for MC-PMF and 0.5 for IC-PMF) was utilized to identify VOC emission sources. Similar eight main sources were found, albeit with differing …
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Decadal trends in atmospheric organic aerosol :
… of how changes in OA relate to changes in emissions sources, anthropogenic-biogenic emissions interactions, altered chemistry, and more. This work represents a two-fold effort to better constrain our understanding of OA trends spatially, temporally, and chemically. First, trends in aerosol …
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Time Dependent Uptake of Volatile Organic Compounds on Silica and the Observation and Quantification of Ambient Sesquiterpenes in Virginia
… Sesquiterpenes represent one class of biogenic emissions not well constrained with regards to SOA influence due to their low volatility and concentrations relative to more abundant terpenoid species. Ambient measurements of sesquiterpenes through the Semi-Volatile Thermal desorption …
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Ice core methane and carbon monoxide as tracers of the terrestrial biosphere since the pre-industrial
… that historical anthropogenic fossil fuel emissions have been largely underestimated by bottom-up approaches. Then, to explain a plateau in isotopic enrichment in 1970 CE, biogenic emissions may have declined by up to 20 Tg yr-1 from 1940 to 1960 CE. If wetlands are assumed to be the source …
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Regional CO₂ flux estimates for South Africa through inverse modelling
… provides a top-down technique of verifying emissions and uptake of carbon dioxide (CO₂) from both natural and anthropogenic sources. It relies on accurate measurements of CO₂ concentrations at appropriately placed sites and "best-guess" initial estimates of the biogenic and anthropogenic …