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Full-Text Articles in Physical Sciences and Mathematics
Impact Of Interlayer Cation Composition And Strongly Bound Water On Smectite ẟ²H, As Determined By A Modified Tcea Method, Nadine J. Kanik
Impact Of Interlayer Cation Composition And Strongly Bound Water On Smectite ẟ²H, As Determined By A Modified Tcea Method, Nadine J. Kanik
Electronic Thesis and Dissertation Repository
Interlayer cation composition and cation hydration enthalpy can potentially affect the excess hydrogen-yield and δ2H of smectitic clays. Complexities arise from condensed atmospheric water adsorbed on the clay, as it constitutes a potential additional source of hydrogen when attempting to measure the δ2H of structural OH groups. To approach this problem, the δ2H of different cation-saturated, dried forms of six Clay Minerals Society Source Clay smectites were measured. A modified sample drying and on-line High-Temperature-Conversion-Elemental-Analysis (TCEA) Continuous-Flow-Isotope-Ratio-Mass-Spectrometry protocol, facilitated isotopic measurements. A stronger interlayer cation hydration enthalpy (Ca2+>Na+>K+), …
Condition And Function Of Red River Valley Streams Receiving Nutrients From Human Activities In Manitoba, Canada, Kristin J. Painter
Condition And Function Of Red River Valley Streams Receiving Nutrients From Human Activities In Manitoba, Canada, Kristin J. Painter
Electronic Thesis and Dissertation Repository
Small tributary streams are conduits between the landscape and larger waterbodies and provide important ecosystem services including assimilation of nutrients from human activities which may be protective of downstream waterbodies. In the Red River Valley (RRV), Manitoba, numerous nutrient sources including agricultural runoff, livestock manure, and municipal wastewater effluent, have been attributed to the eutrophication of Lake Winnipeg and thus require targeted management to prevent loss of nutrients from land to lake. However, linkages between land-based nutrient-producing human activities in the RRV and the ecological status of the tributaries remain poorly understood. Furthermore, the proportional contribution of each source of …
Paleoproductivity Of Late Holocene Lake Huron, Jamal Khaled Nigim
Paleoproductivity Of Late Holocene Lake Huron, Jamal Khaled Nigim
Electronic Thesis and Dissertation Repository
The paleolimnology of North America’s Lake Huron is described using lead-210 dating, mineralogy, magnetic susceptibility, total organic carbon (TOC), total nitrogen (TN), carbon:nitrogen (C/N) ratio, grain size, and the δ13COM and δ15NTN of organic matter. Sediment cores from Lake Huron’s 6 depositional basins and Georgian Bay span the Medieval Warm Period, Little Ice Age, and Canadian-European settlement. The main organic matter source is lacustrine algae, as indicated by δ13COM, δ15NTN and C/N. Prior to the 19th century, primary production changes are reflected only by small variations in …