...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Environmental Science & Technology >Characterization of colloidal and humic-bound Ni and U in the 'dissolved' fraction of contaminated sediment extracts
【24h】

Characterization of colloidal and humic-bound Ni and U in the 'dissolved' fraction of contaminated sediment extracts

机译：胶态和腐殖质结合的镍和铀在“溶解”的受污染沉积物提取物中的表征

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

The dissolved phase of environmental aqueous samples is generally defined by filtration at 0.2 mu m or even 0.45 mu m. However, it is also acknowledged that colloids < 0.2 mu m suspended in the aqueous phase can be important for determining contaminant availability and mobility. We have used flow field-flow fractionation (FI FFF) and size exclusion chromatography (SEC) coupled to UV-absorbance (UVA) and inductively coupled plasma mass spectrometry (ICP-MS) to study the dissolved organic matter (DOM) and colloidal binding of U and Ni in water extracts of sediments collected from a contaminated area of the Savannah River Site, a U.S. Department of Energy former nuclear materials production and processing facility, near Aiken, SC. High-performance SEC-UVA-ICP-MS was well-suited to the separation of DOM over the molecular weight (MW) range of similar to 200-7000 Da. The ICP-MS element specific data indicated that a significant fraction of U was associated with DOM. Uranium exhibited a bimodal distribution and the other fraction was greater than the exclusion limit for the column and coeluted with Al. Flow FFF was used to size this fraction as colloidal with an approximate effective spherical diameter of 0.09-0.12 mu m. Element specific ICP-MS data confirmed that U and Al were associated with the colloidal phase. High-field FI FFF was also applicable to sizing DOM but resolution was poorer than SEC. The results of this study suggest that "dissolved" U at this site is predominantly either complexed by DOM or bound to a colloidal fraction while Ni is predominately present as labile complexes or the free cation and, therefore, potentially bioavailable.
机译：环境水性样品的溶解相通常通过0.2μm甚至0.45μm的过滤来定义。但是，还应认识到，悬浮在水相中的<0.2微米的胶体对于确定污染物的利用度和迁移率很重要。我们已经使用流场流分级分离（FI FFF）和尺寸排阻色谱（SEC）结合紫外吸收（UVA）和电感耦合等离子体质谱（ICP-MS）来研究溶解的有机物（DOM）和胶体结合萨凡纳河站点受污染区域（美国能源部以前的核材料生产和加工设施，南卡罗来纳州附近）收集的沉积物水提取物中的铀和镍含量高性能SEC-UVA-ICP-MS非常适合于分子量（MW）范围接近200-7000 Da的DOM分离。 ICP-MS元素的特定数据表明，U的大部分与DOM相关。铀表现出双峰分布，其他分数大于色谱柱的排阻极限，并与Al共洗脱。使用流动FFF将这一部分定为胶体的大小，其有效球形直径约为0.09-0.12μm。元素特定的ICP-MS数据证实U和Al与胶体相相关。高场FI FFF也适用于DOM的大小确定，但分辨率比SEC差。这项研究的结果表明，“溶解的” U在此位点主要是被DOM复合或与胶体部分结合，而Ni主要以不稳定的复合物或游离阳离子的形式存在，因此具有潜在的生物利用性。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号