Direct and Indirect Radiolytic Effects in Highly Concentrated Aqueous Solutions of Bromide
Direct and Indirect Radiolytic Effects in Highly Concentrated Aqueous Solutions of Bromide
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DOI：
10.1021/jp2012528
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发表时间：
2011-05-05
影响因子：
2.9
通讯作者：
Mostafavi, Mehran
中科院分区：
文献类型：
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作者：
Balcerzyk, Anna;LaVerne, Jay;Mostafavi, Mehran
使用高浓度的溴化物水溶液来检查伽马射线直接分解水的总自由基产量。溴化物浓度变化至 6 M，此时几乎所有 OH 中心点自由基、H 中心点原子和皮秒范围内产生的水合电子都会氧化溴化物，最终形成 Br-3(-)，这是一种可以使用光谱仪轻松测量的稳定物质。仅考虑在空气存在和酸性条件下水的分解，发现氧化物质的表观产率约为 (10 +/- 0.05) x 10(-7) mol J(-1)。讨论并定量评估了高浓度溶质对辐照剂量的吸收。在 6 M Br- 溶液中，38% 的剂量被溶质吸收，并且 Br- 直接电离。发现直接辐射分解Br-电离产生的自由基的初始产率的最佳值为(9.6+/-0.5)×10(-7)mol J(-1)。
Highly concentrated aqueous solutions of bromide were used to examine the total radical yield in the direct decomposition of water by gamma-rays. Bromide concentrations were varied up to 6 M at which almost all OH center dot radicals, H-center dot atoms, and hydrated electrons produced in the picosecond range oxidize bromide to ultimately form Br-3(-), a stable species that can easily be measured with a spectrometer. Considering only the decomposition of water in the presence of air and in acidic conditions, the apparent yield of oxidizing species is found to be around (10 +/- 0.05) x 10(-7) mol J(-1). The absorption of irradiation dose by the solute at high concentration is discussed and quantitatively evaluated. At 6 M Br- solutions, 38% of the dose is absorbed by solutes and Br- is directly ionized. The optimal value for the initial yield of the radicals produced by direct radiolytic Br- ionization is found to be (9.6 +/- 0.5) x 10(-7) mol J(-1).