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Full-Text Articles in Chemistry
Impact Of Solar Radiation On Perchlorate Formation In The Atmosphere: Evidence From Ice Core Measurements, Bishnu Kunwar
Impact Of Solar Radiation On Perchlorate Formation In The Atmosphere: Evidence From Ice Core Measurements, Bishnu Kunwar
Electronic Theses and Dissertations
Perchlorate, which derives from both anthropogenic and natural sources in the current environment, poses a substantial health hazard to humans as it competes with iodine uptake in the thyroid gland. Consequently, there has been considerable concern about minimizing human exposure to environmental perchlorate by restricting its release from man-made sources. However, the absence of a clear understanding regarding the respective contributions of man-made and natural sources has hindered widespread regulation efforts. A 300-year (1700–2007) Summit, Greenland ice core record from a previous study showed relatively stable perchlorate concentrations in Greenland snow prior to 1980, with some elevated perchlorate levels associated …
The Significance Of A New 11,000-Year Volcanic Record From The South Pole And Inferences From Comparisons With Other Volcanic Records, Derek Lee Brandis
The Significance Of A New 11,000-Year Volcanic Record From The South Pole And Inferences From Comparisons With Other Volcanic Records, Derek Lee Brandis
Electronic Theses and Dissertations
Snow accumulation at the polar regions of the planet preserves chemical substances from the atmosphere creating natural archives. Records of the atmospheric environment including atmospheric chemical composition and the climate can be reconstructed from ice cores from the polar ice sheets. Sulfur emitted by explosive volcanic eruptions is preserved as sulfate in polar snow and can be used to reconstruct the record of volcanic eruptions. Since large volcanic eruptions impact the environment and climate, records of volcanic eruptions from ice cores can help us to study and understand climate change and model the future climate environment. A 1750-m ice core …
Volcanic Impact On Stratospheric Chlorine Chemistry And Perchlorate Formation: Evidence From Ice Cores, Joshua Andrew Kennedy
Volcanic Impact On Stratospheric Chlorine Chemistry And Perchlorate Formation: Evidence From Ice Cores, Joshua Andrew Kennedy
Electronic Theses and Dissertations
Perchlorate, suspected to be chemically formed in both the troposphere and stratosphere, has been recently measured in Arctic snow and ice cores. These comprise both discontinuous snow and ice cores from the Canadian Arctic and a continuous record of perchlorate was compiled from an analysis of Greenland ice cores. While the background perchlorate concentration typically is very low, a few spikes in concentration coinciding with deposition of volcanic sulfate were observed in the Greenland record, suggesting that perchlorate levels in the atmosphere may be impacted by volcanic eruptions. As of yet, no work has been done to investigate the connection …
Development And Validation Of Advanced Analytical Methods For Pesticides, Per- And Polyfluoroalkyl Substances, And Opioids In Soil And Drinking Water, Christopher Skaggs
Development And Validation Of Advanced Analytical Methods For Pesticides, Per- And Polyfluoroalkyl Substances, And Opioids In Soil And Drinking Water, Christopher Skaggs
Electronic Theses and Dissertations
Environmental pollution from contaminants is a serious concern in a world where more and more pesticides and pharmaceuticals are being used, sometimes improperly and in excess. Since pesticides are used on practically every crop on Earth, it’s no surprise that these compounds are detected in soil, water, and processed agricultural commodities meant for human consumption. Additionally, because of the ubiquity of pharmaceuticals, specifically opioids, and their inherent addictive properties, these compounds are being over-consumed. Because current waste-water treatments can be insufficient to remove them from water sources, this consumption has led to the detection of these compounds in drinking water. …
Perchlorate Variations Over 300 Years: Influence Of Human Activities, Volcanic Eruptions And Bolide Events, Kari Peterson
Perchlorate Variations Over 300 Years: Influence Of Human Activities, Volcanic Eruptions And Bolide Events, Kari Peterson
Electronic Theses and Dissertations
Perchlorate, which derives from both anthropogenic and natural sources in the current environment, constitutes a significant health risk to humans because it competitively inhibits iodine uptake by the thyroid gland. Thus, there has been considerable interest in reducing the human exposure to environmental perchlorate by limiting the release of perchlorate from anthropogenic sources. However, a lack of understanding of the relative contributions from anthropogenic and natural sources has prevented widespread regulation. A 300-year ice core perchlorate record from Summit Station, Greenland (1700-2007 C.E.) that extends beyond the onset of the Industrial Revolution (1850 C.E.) is used to assess the anthropogenic …