Plutonium Oxidation States in Corals and in Synthetic Calcium Carbonates

珊瑚和合成碳酸钙中的钚氧化态

• 批准号: 8711852
• 负责人: Richard Dodge
• 金额: $ 2.96万
• 依托单位: Nova Southeastern University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1987
• 资助国家: 美国
• 起止时间: 1987-06-01 至 1989-11-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=8711852&HistoricalAwards=false
• 关键词: Plutonium; Oxidation; States; Corals; Synthetic

Annual growth bands from the coral Montastrea annularis preserve a record of fallout plutonium concentrations which is simply related to the known history of fallout 90-Sr deposition. The relationship between the plutonium concentration in an annual band and in coeval seawater is clouded by ignorance of mechanisms of plutonium uptake by corals and in synthetic calcium carbonates. The coral plutonium oxidation-state signature will be recovered through application to corals of techniques (solvent extraction, coprecipitation, selective adsorption) previously applied to homogeneous aqueous solutions. Comparisons will be made within (by ages of annual bands) and between corals (over taxonomy and geography). Coprecipitaiton experiments will provide models of the physicochemical control of plutonium uptake in calcium carbonate. Coprecipitation of plutonium oxidation states in aragonite will be emphasized, but coprecipitations with calcite and aragonite will be compared. In all cases rate of precipitation will be controlled. Results for plutonium coprecipitation will be compared with those obtained for actinide analog (Th, U, Np, Am) for the plutonium oxidation states.

珊瑚Montastrea annularis的年生长带 保存放射性尘埃钚浓度的记录， 简单地说，这与已知的沉降物90-Sr沉积历史有关。 年钚浓度与 在同时代的海水中，由于对机制的无知， 珊瑚和合成钙对钚的吸收 碳酸盐。 珊瑚钚的氧化态特征将是 通过对珊瑚应用技术（溶剂 萃取、共沉淀、选择性吸附） 适用于均匀的水溶液。 比较将 在（每年的乐队年龄）和珊瑚之间（超过 分类学和地理学）。 共沉淀实验将提供 碳酸钙中钚吸收的物理化学控制。 文石中钚氧化态的共沉淀将 强调，但共沉淀与方解石和文石 将被比较。 在所有情况下，降水率将是 控制。 钚共沉淀的结果将是 与锕系元素类似物（Th，U，Np，Am）的结果相比 对于钚的氧化态。