Copper (Cu) Ligand Distribution Across Multiple Detection Windows in Natural Waters: Influence of pH, DOC Abundance, and Ligand Composition

天然水中铜 (Cu) 配体在多个检测窗口中的分布：pH、DOC 丰度和配体组成的影响

• 批准号: 0838404
• 负责人: Gaboury Benoit
• 金额: $ 18.85万
• 依托单位: Yale University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-08-01 至 2013-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0838404&HistoricalAwards=false
• 关键词: Copper; Cu; Ligand; Distribution; Across

Proposal 0838404AbstractThis award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). This first study to measure Cu binding ligand abundance across the full range of strength from very weak to very strong in two lakes would cover a range of pH, DOC (dissolved organic carbon) amount and composition, trophic status, and level of watershed development (both clean and contaminated sites). Chemical speciation controls a metal?s environmental behavior and biological availability in natural waters. Speciation is largely controlled in aquatic systems by metal-binding ligands that decrease the free (aquo) metal ion concentration through the formation of stable metal complexes. I hypothesize that the relationship between abundance ([CL]) and stability (K?) of naturally occurring, copper-binding, aquatic ligands follows the form [CLi]  K?i-n, and that this is caused by the relative abundance and strength of functional groups based on the elements O, N, and S. Scatter around this trend is introduced by variations in pH and amount of DOC. The relationship between CL and K? has a profound influence on the relative importance of strong and weak ligands, the concentration of free reactive copper (Cu2+), and the environmental behavior, toxicity, and bioavailability of copper. I will test these hypotheses across the full range of ligand strength (logK? from 5 to 15) with multiple detection windows (≥ 5) via a range of analytical methods. DOC composition (O, N, S), the importance of reduced S ligands, a possible DOC-CL correlation, and the influence of pH will all be measured as well. Finally, I hope to evaluate the utility of pseudopolarography for measuring Cu binding ligands in fresh waters.

提案0838404摘要该奖项是根据2009年《美国复苏和再投资法案》(公法111-5)资助的。这是首次在两个湖泊中测量从很弱到很强的所有强度范围内铜结合配体丰度的研究，将涵盖一系列pH、DOC(溶解有机碳)数量和组成、营养状况以及流域发展水平(包括清洁和受污染的地点)。化学形态控制着一种金属？S在天然水域中的环境行为和生物有效性。在水生体系中，形态形成在很大程度上受到金属结合配体的控制，这些配体通过形成稳定的金属络合物来降低自由(水)金属离子的浓度。我假设丰度([CL])和稳定性(K？)之间的关系自然产生的铜结合的水生配体遵循[cli]&amp；#61621；K？i-n的形式，这是由于基于O、N和S元素的官能团的相对丰度和强度造成的。CL与K？对强弱配体的相对重要性、自由活性铜(Cu2+)的浓度以及铜的环境行为、毒性和生物可利用性有着深远的影响。我将在整个配基强度范围内测试这些假设(logK？从5到15)通过一系列分析方法具有多个检测窗口(&amp；#8805；5)。DOC的组成(O，N，S)，还原的S配体的重要性，可能的DOC-CL相关性，以及pH的影响都将被测量。最后，我希望评价伪极谱在淡水中铜结合配体测定中的应用。