...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>European Journal of Soil Science >Transfer functions for solid-solution partitioning of cadmium, copper, nickel, lead and zinc in soils: derivation of relationships for free metal ion activities and validation with independent data
【24h】

Transfer functions for solid-solution partitioning of cadmium, copper, nickel, lead and zinc in soils: derivation of relationships for free metal ion activities and validation with independent data

机译：土壤中镉，铜，镍，铅和锌的固溶分配的传递函数：自由金属离子活度关系的推导和独立数据的验证

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

Models to predict the solid-solution partitioning of trace metals are important tools in risk assessment, providing information on the biological availability of metals and their leaching. Empirically based models, or transfer functions, published to date differ with respect to the mathematical model used, the optimization method, the methods used to determine metal concentrations in the solid and solution phases and the soil properties accounted for. Here we review these methodological aspects before deriving our own transfer functions that relate free metal ion activities to reactive metal contents in the solid phase. One single function was able to predict free-metal ion activities estimated by a variety of soil solution extraction methods. Evaluation of the mathematical formulation showed that transfer functions derived to optimize the Freundlich adsorption constant (Kf), in contrast to functions derived to optimize either the solid or solution concentration, were most suitable for predicting concentrations in solution from solid phase concentrations and vice versa. The model was shown to be generally applicable on the basis of a large number of independent data, for which predicted free metal activities were within one order of magnitude of the observations. The model only over-estimated free-metal ion activities at alkaline pH (>7). The use of the reactive metal content measured by 0.43 m HNO rather than the total metal content resulted in a close correlation with measured data, particularly for nickel and zinc.
机译：预测痕量金属固溶体分配的模型是风险评估中的重要工具，可提供有关金属的生物有效性及其浸出的信息。迄今为止发布的基于经验的模型或传递函数在所使用的数学模型，优化方法，确定固相和固溶相中金属浓度的方法以及土壤性质方面均存在差异。在这里，我们在得出我们自己的将自由金属离子活性与固相中反应性金属含量相关的传递函数之前，回顾了这些方法论方面。一个功能可以预测通过多种土壤溶液提取方法估算出的自由金属离子活性。数学公式的评估表明，与优化固相或溶液浓度的函数相反，为优化Freundlich吸附常数（Kf）而导出的传递函数最适合根据固相浓度来预测溶液中的浓度，反之亦然。该模型在大量独立数据的基础上被普遍证明是适用的，对于这些数据，预测的自由金属活度在观测值的一个数量级内。该模型仅高估了碱性pH（> 7）下的自由金属离子活性。使用由0.43 m HNO测得的活性金属含量而不是总金属含量导致与测得数据密切相关，特别是对于镍和锌。

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