重金属离子快速检测技术研究与应用进展

在突发环境污染事件和区域生态风险筛查中迫切需要环境样品中重金属离子的快速检测技术手段。环境样品中重金属离子的快速检测技术有电化学方法和生物学方法。电化学检测方法主要是阳极溶出伏安法(AnodicStripping Voltammetry,ASV),可以同时检测多种重金属离子,有标准化认证的产品,但是检测成本相对较高。随着纳米粒子技术(Nanoparticles,NPs)和石英微天平分析技术(Quartz Crystal Microbalance,QCM)的引入,ASV法的检测成本将不断降低;生物检测方法包括免疫检测(Immunoassay,IA)和功能DNA(Functional DNA)检测技术。重金属离子的免疫检测技术样品通量大,检测成本低,已经广泛用于食品行业,其中汞离子的免疫检测方法已经成为环境样品标准检测方法之一。免疫检测传感器技术将拓展重金属离子的快速检测的应用空间。功能DNA传感器检测的研究为重金属离子的快速检测提供了新的技术手段,但是这些仅限于实验室研究,还没有达到实际应用的水平。     

小型燃煤工业锅炉NO_x形成与释放规律模拟研究

NOx是我国十二五期间重点控制的污染物,燃煤工业锅炉是其重要来源。为了研究燃煤工业锅炉NOx的形成与释放规律,在实验室模拟了不同煤种的燃烧过程。采用原煤/焦炭燃烧法分别研究挥发分氮和焦炭氮生成NOx的反应,探讨燃料型NOx的形成与释放规律,并解释试验模拟条件下燃煤NOx产污系数和现场实测值的差异。结果表明,试验中烟煤、无烟煤、煤焦的NO转化率平均值分别为25.77%,22.17%和11.98%,产污系数平均值分别为4.31,5.08和2.00kg/t,高于现场实测结果核算值。燃煤工业锅炉NOx以燃料型为主,燃料型NOx的形成和释放是一个复杂的多相反应过程,由挥发分氮的氧化还原反应和焦炭氮的氧化还原反应组成,煤种、温度、空气流量、粒径、氧含量等因素对4种反应各自影响及影响程度并不相同。     

福州城市边缘区森林土壤重金属污染特征及评价

为掌握福州城市边缘区森林土壤重金属污染特征,选取10个典型区域作为研究对象,分析森林土壤中Zn、Mn、Cr、Pb、Cu 5种重金属的含量及分布特征,并采用单项污染指数和综合污染指数法对土壤进行质量评价,结果表明:Cr、Pb是该区土壤重金属污染最主要的元素;Zn、Cu、Pb、Cr含量随土层深度增加而减少,Mn则相反;Zn...     

兰州银滩湿地5种植物对重金属吸附能力的分析

利用原子吸收分光光度法测定兰州银滩湿地5种植物及其生长土壤(表层)中Cu、Pb、Zn的含量,结果表明,采样区域表层土壤存在轻度Cu、Zn、Pb污染,其中Cu、Pb的来源或污染途径可能相同,且Cu、Zn、Pb的生物可利用性较低,TCLP生态风险评价显示均小于国际标准值;采样区域表层土壤Cu、Zn、Pb总量与TCLP提取量...     

南淝河沉积物有机物污染及其生态风险评价

参照文献报道的提取方法,利用GC和HPLC对南淝河不同河段沉积物中的四种浓度较高有机污染物(苯酚、氯代苯类、多环芳烃(PAHs)和邻苯二甲酸酯类(PAEs))进行了定量分析,结果表明其浓度高低顺序为多环芳烃类＞邻苯二甲酸酯类＞氯代苯类＞苯酚类.与世界各地表层沉积物中有机污染物的浓度进行对比,分析了南淝河各河段沉积物的有...     

北方某钢铁厂部分厂区土壤重金属污染的初步调查

对北方某即将搬迁钢铁厂的部分厂区土壤重金属进行了初步调查,主要利用SPSS相关和变异分析、Surfer空间分析及归一化处理对重金属污染的空间分布特征进行了描述。一区污染最为严重,有Hg、Mn、Zn、As、Cr和Cu;二区污染物主要为As、Pb和Zn;三区污染主要有As、Cr和Co;四区污染物有Cr、Co、Mn、Cu和Pb,污染相对较低。研究为调查区域搬迁后的土地规划提供了科学依据。     

生物炭输入对土壤污染物迁移行为的影响

重点综述了生物炭输入对土壤中污染物的吸附固持作用及生物有效性的影响,分析其作为土壤添加剂消减土壤污染风险的有效性,为生物炭在土壤中的应用研究提供依据。     

实施污染物总量控制中的环境监测

随着经济的发展,由发展带来的污染问题也愈发的严重,如何治理和监测环境问题显得十分重要。文章旨在研究环境监测在对污染物总量控制上的作用做出分析,指出目前环境监测上存在的不足,提出建议和解决方案,更好的发挥环境监测的作用。     

Arbuscular mycorrhizal fungal phylogenetic groups differ in affecting host plants along heavy metal levels

Arbuscular mycorrhizal fungi（AMF） are important components of soil microbial communities,and play important role in plant growth. However, the effects of AMF phylogenetic groups（Glomeraceae and non-Glomeraceae） on host plant under various heavy metal levels are not clear. Here we conducted a meta-analysis to compare symbiotic relationship between AMF phylogenetic groups（Glomeraceae and non-Glomeraceae） and host plant functional groups（herbs vs. trees, and non-legumes vs. legumes） at three heavy metal levels. In the meta-analysis, we calculate the effect size（ln（RR）） by taking the natural logarithm of the response ratio of inoculated to non-inoculated shoot biomass from each study. We found that the effect size of Glomeraceae increased, but the effect size of non-Glomeraceae decreased under high level of heavy metal compared to low level. According to the effect size, both Glomeraceae and non-Glomeraceae promoted host plant growth, but had different effects under various heavy metal levels. Glomeraceae provided more benefit to host plants than non-Glomeraceae did under heavy metal condition, while non-Glomeraceae provided more benefit to host plants than Glomeraceae did under no heavy metal. AMF phylogenetic groups also differed in promoting plant functional groups under various heavy metal levels.Interacting with Glomeraceae, herbs and legumes grew better than trees and non-legumes did under high heavy metal level, while trees and legumes grew better than herbs and non-legumes did under medium heavy metal level. Interacting with non-Glomeraceae, herbs and legumes grew better than trees and non-legumes did under no heavy metal. We suggested that the combination of legume with Glomeraceae could be a useful way in the remediation of heavy metal polluted environment.     

Mo-modified Pd/Al2O3 catalysts for benzene catalytic combustion

Mo-modified Pd/Al2O3catalysts were prepared by an impregnation method and tested for the catalytic combustion of benzene. The catalysts were characterized by N2 isothermal adsorption, X-ray diffraction（XRD）, X-ray photoelectron spectroscopy（XPS）, temperatureprogrammed desorption of NH3（NH3-TPD）, H2temperature-programmed reduction（H2-TPR）, and high-angle annular dark-field scanning transmission electron microscopy（HAADF-STEM）. The results showed that the addition of Mo effectively improved the activity and stability of the Pd/Al2O3catalyst by increasing the dispersion of Pd active components, changing the partial oxidation state of palladium and increasing the oxygen species concentration on the surface of catalyst. In the case of the Pd-Mo/Al2O3catalyst,benzene conversion of 90% was obtained at temperatures as low as 190°C, which was 45°C lower than that for similar performance with the Pd/Al2O3catalyst. Moreover, the 1.0% Pd-5% Mo/Al2O3catalyst was more active than the 2.0% Pd/Al2O3catalyst. It was concluded that Pd and Mo have a synergistic effect in benzene catalytic combustion.