Quantifying the availability and the stability of trace cationic elements in fly ash

For adsorption-desorption controlled leaching processes, the total leachable mass and the adsorption constant are parameters representing the availability and the stability of trace elements in solid media. With these parameters, one can predict the leaching behavior of trace elements from solids under various pH and solid-to-liquid ratio conditions. An approach was developed in this paper to determine these parameters for model elements Cu(II), Cd(II), and Ni(II) in fly ash. This approach consists of a batch equilibrium titration, a batch equilibrium leaching with and without target element addition, and mathematical modeling. Results indicated that the adsorption constant of a trace element can be determined by modeling the adsorption ratio of the added element to the system as a function of pH. Results also indicated that the trace element originally present in fly ash had similar adsorption-desorption behavior as that added externally. By modeling the batch leaching data with and without external element addition, the total leachable mass and adsorption constant of the target element can be determined simultaneously. The total leachable mass is in agreement with experimental data from 50mM EDTA extraction.     

Short-term effects and economic burden assessment of ambient air pollution on hospitalizations for schizophrenia

Environmental Science and Pollution Research - The evidence on the health and economic impacts of air pollution with schizophrenia is scarce, especially in developing countries. In this...     

Influence of shrub root combinations and spacing on slope stability: study case at the Yongding River flooding regime,Langfang, China

Environmental Science and Pollution Research - Research on the mechanism of plant root–soil consolidation is a current focus in research into the ecological restoration of banks. The...     

基于卷积神经网络识别三维荧光光谱的水污染溯源研究

为快速、准确地追溯水中污染物来源,及时阻断污染,为生态环境管理部门提供科学的技术支撑,更好履行"三个说得清"中的"说得清污染来源",以昆明市安宁市8家重点企业为研究对象,采集企业内各工段废水进行三维荧光检测获得三维荧光谱图,采用目视剔除散射区域-线性归一化方法对原始荧光谱图进行预处理,基于ConvNet卷积神经网络构建水污染溯源模型并进行溯源。结果表明,目视剔除散射区域-线性归一化方法可有效剔除荧光谱图中瑞利散射区域,同时增强因水样稀释而衰弱的荧光特征;构建的溯源模型可成功识别实际废水的三维荧光谱图,识别正确率高达75%,是一种有效溯源水中污染物来源的方法。