模拟酸雨作用下红壤中CU2+的释放动力学

利用土柱研究了模拟酸雨淋溶下红壤中铜离子的释放动力学 .结果表明 :铜离子的累积释放量随时间的延长迅速增加 ,2 4h后基本达到平衡 ,48h后铜离子的释放明显受酸雨pH值的影响 ,pH >3 5时铜离子的释放规律依然相同 ,但pH 2 5时释放量却再次增加 .该过程可分为快速释放阶段和准平衡阶段 ,可用修正的Elovich方程和双常数速率方程来描述 ,且修正的Elovich方程更优     

广州地区酸雨特征及其对植物的影响研究

根据酸雨监测资料，分析了广州地区酸雨的时间变化规格九空间分布特征，探讨了广州地区酸雨的主要形成原因和影响因素，对酸雨对广州地区植物的影响进行了评价，指出酸雨已经对广州地区植物的生存环境造成了严重危害，必须采取更为有效的措施来防治酸雨污染，并提出了一些具体的防治措施。     

电催化氧化法处理染料废水的影响因素及动力学

以钛涂膜极板为阳极、石墨极板为阴极、Fe2O3/γ-Al2O3为多相催化剂,构建电-多相催化氧化体系,研究了该体系对酸性大红模拟染料废水中COD的去除效果及其影响因素,优化了实验条件,并初步探讨了COD的降解机理。结果表明,在槽电压20 V,pH 4,曝气量0.24 m3/h,极板间距3 cm的条件下,COD的去除率最高,达到64.5%;COD的降解近似符合一级动力学方程:ln(C0/C)=0.0034t+0.719。在电-多相催化氧化体系中,废水中的有机物被直接矿化或降解为小分子有机物。     

Investigation into atmospheric deposition through precipitation studies at New Delhi (India)

Rain water samples were collected during the monsoon of 1994, using automatic wet-only and manual bulk collectors at a height of 30 m above the ground at the National Physical Laboratory, New Delhi. The average pH of the rain water was 5.7 and its chemical composition was dominated by NH₄ and SO₄. The free acidity of the rain water was found to be due to S04 rather than N03 and it was mainly neutralized by NH₄ and Ca. Calculation of sea salt fraction and enrichment factor revealed that this site is free for marine influence. On an average the bulk samples had 13% higher concentration than that of wet-only samples which may be due to the deposition of soil-derived particles during the 24 h period of exposure. The higher neutralization factors of Ca and Mg in bulk samples and highest dry deposition rates for Ca in comparison to other components, indicated the positive interference of dust particles in neutralization.     

基于气流轨迹聚类的大气输送对丹东市酸雨形成影响

利用HYSPLIT4.8后推气流轨迹模式对辽宁省丹东市2007年的降水来源进行气流轨迹模拟,再通过聚类分析方法得到气流的平均轨迹分布,从而分析丹东市降水的来源及各方向气流对酸雨形成的影响.研究表明,丹东市酸雨污染主要受外来输送影响.在季风影响下,6-9月的雨季,来自西南和东南方向气流多经过河北、京津、山东等工业发达地区或朝鲜半岛,SO2和NO2污染较重,且运行高度低,地面污染贡献大,气流携带大量致酸前体物,在丹东形成酸性降水频率高,导致其酸雨污染严重.而来自西北方向的气流经过蒙古国、内蒙古自治区、辽宁省西部等工业欠发达地区,且多在高空运行,气流相对干净,很少形成酸性降水.     

成都市不同粒径大气颗粒物中水溶性酸性离子分析

大气颗粒物是成都目前大气环境主要污染物之一。文章通过Andersen分级采样器采样,对成都市东郊(原工业区)2006年下半年不同粒径的大气颗粒物及其水溶性酸性离子的含量进行了分析,在此基础上对比分析了雾天条件下的污染特征。结果表明,大气颗粒物及其酸性离子主要分布在0.65～3.3μm的粒径范围,颗粒物中水溶性酸性离子的平均含量大小关系为:[SO42-]>[NO3-]>[Cl-]>[F-]>[NO2-].雾天颗粒物的浓度水平是正常天气下的1～3倍。     

马鞍山市酸雨污染分析及控制对策研究

从马鞍山市降水常规监测数据资料入手 ,比较详细地分析了该市酸雨时空分布特征、原因以及降水酸度和酸雨频率年度变化情况 ,并结合马鞍山市有关环境资料对该市酸雨发展趋势作了较深的分析 ,也对酸雨污染控制对策作了一定的研究探讨。研究结果表明 ,该市存在酸雨污染问题 ,上半年比下半年污染重 ,主要集中在一中点 ,二氧化硫是影响降水酸度的主要因素 ,酸雨类型以硫酸型为主。随着经济发展 ,酸雨污染有扩大趋势 ,必须采取果断措施进行治理。     

Microbial communities in acid water environments of two mines, China

To understand the compositions and structures of microbial communities in different acid-aqueous environments, a PCR-based cloning approach was used. A total of five samples were collected from two mines in China. Two samples, named as G1 and G2, were acid mine drainage (AMD) samples and from Yunfu sulfide mine in Guangdong province, China. The rest of the three samples named as D1, DY and D3, were from three sites undertaking bioleaching in Yinshan lead-zinc mine in Jiangxi province, China. Phylogenetic analysis revealed that bacteria in the five samples fell into six putative divisions, which were α-Proteobacteria, β-Proteobacteria, γ-Proteobacteria, Firmicutes, Actinobacteria and Nitrospira. Archaea was only detected in the three samples from Yinshan lead-zinc mine, which fell into two phylogenentic divisions, Thermoplsma and Ferroplasma. In addition, the results of principal component analysis (PCA) suggested that more similar the geochemical properties in samples were, more similar microbial community structures in samples were.     

Suitable gamma energy for gamma-spectrometric determination of U in surface soil samples of a high rainfall area in India

The paper presents a systematic study on suitability of various gamma lines for monitoring of ²³⁸U activity in soil samples around a uranium mineralized zone of Kylleng Pyndengsohiong Mawthabah (Domiasiat), Meghalaya in India. The area lies in a plateau region which recieves the highest average annual rainfall (12,000 mm) in the world. The geochemical behaviour of the uranium and its daughter products at such wet climatic conditions imposes restrictions to assess ²³⁸U through gamma lines of radon decay products. Soil samples were collected from nine locations around the uranium mineralization zone for analysis. The ratio of the concentration of uranium obtained from gamma energies of radium daughter products to the 63.29 keV of ²³⁴Th was found to vary from 1.01 to 2.07, which indicates a pronounced disequilibrium between uranium and radium daughters. The results obtained from various gamma energies were validated from the data generated by Instrumental Neutron Activation Analysis (INAA) technique. The ²³⁸U activities from the two analytical methods show a well fitted regression line with correlation coefficient 0.99 which validates the reliability of 63.29 keV energy for estimation of uranium in such conditions.     

The effect of nitrogen deposition on the species richness of acid grasslands in Denmark: a comparison with a study performed on a European scale

The effect of atmospheric nitrogen deposition on the species richness of acid grasslands was investigated by combining data from a large Danish monitoring program with a large European data set, where a significant non-linear negative effect of nitrogen deposition had been demonstrated (Stevens et al., 2010). The nitrogen deposition range in Denmark is relatively small and when only considering the Danish data a non-significant decrease in the species richness with nitrogen deposition was observed. However, when both data sets were combined, then the conclusion of the European survey was further corroborated by the results of the Danish monitoring. Furthermore, by combining the two data sets a more comprehensive picture of the threats to the biodiversity of acid grasslands emerge; i.e., species richness in remnant patches of acid grassland in intensively cultivated agricultural landscapes is under influence not only from nitrogen deposition, but also from current and historical land use.