Concentrations and chemical forms of potentially toxic metals in road-deposited sediments from different zones of Hangzhou, China

The 25 road-deposited sediments were collected from five different land-use zones (industrial, residential, commercial, park, and countryside) in Hangzhou, China. The concentrations of metals (Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, and Zn) in these samples were determined using the ICP-AES after digestion with the mixture of HNO3-HF-HCl (aqua regia), and chemically fractionated using the modified BCR (the European Community Bureau of Reference) sequential extraction procedure. The highest metal concentration level was detected in the sample from industrial zone and commercial zone having heavy traffic. While the lowest metal level was noted in the street dust sample from residential zone, park, and countryside zone. The mobility sequence based on the sum of the BCR sequential extraction stages was: Zn (80.28%), Pb (78.68%), Cd (77.66%) ＞ Cu (73.34%) ＞ Mn (67.92%) ＞ Co (41.66%) ＞ Ni (30.36%) ＞ Cr (21.56%), Fe (20.86%). Correlation analysis and principal component analysis were applied to the data matrix to evaluate the analytical results and to identify the possible pollution sources of metals. Factor analysis showed that these areas were mainly contaminated by three sources, namely lithology, traffic, and industry.     

地理腐蚀因子的建立及其应用

依据铝合金在海洋大气中的腐蚀机理,对沿海地区空气中气溶胶的产生、转移、沉积进行了研究,并对影响因素进行了分析.通过研究各影响参数之间的函数关系,建立了由具有直接物理意义的参数(如风速、风向、湿度、地理环境等)联合表示的地理腐蚀因子.将地理腐蚀因子与不同试验点实验试件的腐蚀质量损失进行对比研究,良好的对应关系证明了用地理...     

长三角重点行业大气污染物排放及控制对策

研究重点分析了长江三角洲地区电力和水泥行业的大气污染物排放特征,并结合相关行业统计数据和污染物排放因子,对2004年这两个重点行业的大气污染物排放量进行了估算。结论如下:长三角地区火电行业2004年SO2、烟尘、NOX和燃煤大气汞排放量分别为149.2×104t、21.1×104t、87.6×104t和13.7t。2004年江、浙、沪三地水泥行业共排放工艺粉尘76.2×104t,其中PM10为70.1×104t、PM2.5为45.9×104t,气态污染物SO2、NOX、CO和氟化物排放量分别为12.4×104t、49.5×104t、247.9×104t和7.4×104t。并对长三角地区电力和水泥行业的污染控制问题提出一些相关举措。     

典型高山堰塞湖湖滨带和缓冲带的划定及生态修复思路——以镜泊湖为例

镜泊湖是中国最大、世界第二大高山堰塞湖,具有特殊的地形地貌,属于典型通江型深水湖泊。通过对镜泊湖及周边生态环境调查,划定了湖滨带和缓冲带的类型及宽度。基于镜泊湖岸带地形地貌特征及水文情况,将镜泊湖湖滨带划分为山体型、大堤型、道路型、河口型、村落型、农田型6种类型,将镜泊湖缓冲带划分为山体型、农田型、村落型3种类型。结合湖滨带和缓冲带的生境、土地利用方式、土壤侵蚀状况及植被分布现状等因素,阐述镜泊湖湖滨带和缓冲带生态环境面临的主要问题,提出镜泊湖湖滨缓冲带生态修复思路,以期为镜泊湖湖滨缓冲带的生态保护及修复提供参考。     

Catalytic activities and mechanism of formaldehyde oxidation over gold supported on MnO<Subscript>2</Subscript> microsphere catalysts at room temperature

MnO₂ microspheres with various surface structures were prepared using the hydrothermal method, and Au/MnO₂ catalysts were synthesized using the sol-gel method. We obtained three MnO₂ microspheres and Au/MnO₂ samples: coherent solid spheres covered with wire-like nanostructures, solid spheres with nanosheets, and hierarchical hollow microspheres with nanoplatelets and nanorods. We investigated the properties and catalytic activities of formaldehyde oxidation at room temperature. Crystalline structures of MnO₂ are the main factor affecting the catalytic activities of these samples, and γ-MnO₂ shows high catalytic performance. The excellent redox properties are responsible for the catalytic ability of γ-MnO₂. The gold-supported interaction can change the redox properties of catalysts and accelerate surface oxygen species transition, which can account for the catalytic activity enhancement of Au/MnO₂. We also studied intermediate species. The dioxymethylene (DOM) and formate species formed on the catalyst surface were considered intermediates, and were ultimately transformed into hydrocarbonate and carbonate and then decomposed into CO₂. A proposed mechanism of formaldehyde oxidation over Au/MnO₂ catalysts was also obtained.     

The effects of autophagy in rat tracheal epithelial cells induced by silver nanoparticles

Environmental Science and Pollution Research - The massive use of silver nanoparticles (AgNPs) is potentially harmful to exposed humans. Although previous studies have found that AgNPs can induce...     

A review on fabricating functional materials by heavy metal–containing sludges

Environmental Science and Pollution Research - With the development of industry, sustainable use of natural resources has become a worldwide hot topic. Heavy metal–containing sludge (HMS) is...     

海平面上升叠加风暴潮对2050年中国海洋经济的影响研究

本研究基于ArcGIS的淹没模型与夜光遥感的GDP空间化处理结果,同时结合对2050年中国海洋经济增长预测,评估海平面上升叠加风暴潮三种情景对中国沿海各省市海洋经济的影响效应。模拟结果表明:海平面上升叠加风暴潮与天文潮的CHmax-0.3 m情景下全国海洋经济损失最大,2050年损失达到35444.59亿元,占海洋生产总值的9.39%;从2050年各省海洋经济损失比例来看（CHmax-0.3 m情景）,辽宁省损失比例最大,其次为广东省,福建省和广西省;从各省海洋经济损失的绝对值来看,在海平面上升0.3 m的三种情景下,广东、辽宁、江苏、山东均为海洋经济损失绝对值最大的四个省份。     

基于GIS和RS的市域尺度下的植被NPP研究

在GIS和RS支持下,利用土地利用类型数据、地面气象数据和遥感影像数据,以青岛市为例,研究了市域尺度下的植被NPP空间分布特征.结果表明:青岛市NPP值为0~288 g·m-2·a-2,林地NPP值较高,耕地次之,建成区等区域最小.在小尺度区域内,NPP分布受土地利用类型影响较大,受气象因素影响较小.NPP模块在数据获取上比较容易,仅利用土地利用类型数据、地面气象数据和遥感数据就可以对陆地植被NPP进行计算,实际应用可操作性强.30 m分辨率植被NPP计算值更适宜于在市级小尺度区域内应用.     

公交车车内噪声测量及降噪措施的探索

针对人们普遍感到现行公交车内噪声大的情况,对广州市液化石油气新型空调公交车内的噪声进行了噪声实测,测量结果显示公交车内的噪声在70 dB以上.对公交车上主要噪声源和对车内噪声的影响因素进行分析,针对公交车上主要的噪声源和影响因素,对测试公交车进行简单的改装,然后对改装车辆进行测量,结果显示减噪效果相当明显.因此,对于目前广州公交车噪声偏大的实际情况,提出了有效降低车辆内部噪声的主要措施.