淮安市农产品中重金属及有机氯、有机磷农药残留量调查

淮安市环境监测中心站于1999年－2000年对淮安市农产品中重金属以及有机氯、有机磷农药残留量进行了调查。结果表明，粮食和蔬菜作物中，六六六的4种同分异构体只有γ－六六六能检出，检出率分别为24．0％和51．7％，都未超标；DDT的4种同分异要体均未检出；有机磷农药的检出率分别为5％和25％，其中蔬菜中敌敌畏含量出现个别超标现象，倍硫磷、乐果和杀螟松在粮食和蔬菜作物中的含量都不超标。重金属中金属“五毒”在粮食和蔬菜作物中，只有Cr和Pb能检出，Cd、Hg和As都未检出，Cu、Zn和Mn能检出，但不超标。提出，应严格按照农牧渔业部和卫生部颁发的《农药安全使用规定》用药，多使用高效低残留量的“绿色农药”；农业、环保和卫生部门必须加强合作，对蔬菜生产销售的全过程进行监督监测，以确保生产无公害蔬菜。     

高铁酸钾预处理强化污泥破解及厌氧产酸

在序批式污泥厌氧反应器中探究了高铁酸钾对污泥破解及厌氧产酸的影响。实验结果表明高铁酸钾对污泥具有较强的破解性,当高铁酸钾的质量浓度由0 mg/L增加至16 mg/L时,溶解性COD与总COD的比值由6.2%升至35.6%。同时污泥液相中溶解性蛋白质的质量浓度由561 mg/L增加至1 365 mg/L。高铁酸钾的浓度与挥发性悬浮固体(VSS)的减量具有一定的线性关系。当高铁酸钾的质量浓度为8 mg/L时,污泥厌氧产挥发性脂肪酸最大,并且最大值为895 mg/L,其浓度是空白组2.56倍。     

Accumulation of heavy metals in native Andean plants: potential tools for soil phytoremediation in Ancash (Peru)

Metal contamination is a recurring problem in Peru, caused mainly by mine tailings from a past active mining activity. The Ancash region has the largest number of environmental liabilities, which mobilizes high levels of metals and acid drainages into soils and freshwater sources, posing a standing risk on human and environmental health. Native plant species spontaneously growing on naturally acidified soils and acid mine tailings show a unique tolerance to high metal concentrations and are thus potential candidates for soil phytoremediation. However, little is known about their propagation capacity and metal accumulation under controlled conditions. In this study, we aimed at characterizing nine native plant species, previously identified as potential hyperaccumulators, from areas impacted by mine tailings in the Ancash region. Plants were grown on mine soils under greenhouse conditions during 5 months, after which the concentration of Cd, Cu, Ni, Pb, and Zn was analyzed in roots, shoots, and soils. The bioaccumulation (BAF) and translocation factor (TF) were calculated to determine the amount of each metal accumulated in the roots and shoots and to identify which species could be better suited for phytoremediation purposes. Soil samples contained high Cd (6.50–49.80 mg/kg), Cu (159.50–1187.00 mg/kg), Ni (3.50–8.70 mg/kg), Pb (1707.00–4243.00 mg/kg), and Zn (909.00–7100.00 mg/kg) concentrations exceeding national environmental quality standards. After exposure to mine tailings, concentrations of metals in shoots were highest in Werneria nubigena (Cd, 16.68 mg/kg; Cu, 41.36 mg/kg; Ni, 26.85 mg/kg; Zn, 1691.03 mg/kg), Pennisetum clandestinum (Pb, 236.86 mg/kg), and Medicago lupulina (Zn, 1078.10 mg/kg). Metal concentrations in the roots were highest in Juncus bufonius (Cd, 34.34 mg/kg; Cu, 251.07 mg/kg; Ni, 6.60 mg/kg; Pb, 718.44 mg/kg) and M. lupulina (Zn, 2415.73 mg/kg). The greatest BAF was calculated for W. nubigena (Cd, 1.92; Cu, 1.20; Ni, 6.50; Zn, 3.50) and J. bufonius (Ni, 3.02; Zn, 1.30); BCF for Calamagrostis recta (Cd, 1.09; Cu, 1.80; Ni, 1.09), J. bufonius (Cd, 3.91; Cu, 1.79; Ni, 18.36), and Achyrocline alata (Ni, 137; Zn, 1.85); and TF for W. nubigena (Cd, 2.36; Cu, 1.70; Ni, 2.42; Pb, 1.17; Zn, 1.43), A. alata (Cd, 1.14; Pb, 1.94), J. bufonius (Ni, 2.72; Zn, 1.63), and P. clandestinum (Zn, 1.14). Our results suggest that these plant species have a great potential for soil phytoremediation, given their capability to accumulate and transfer metals and their tolerance to highly metal-polluted environments in the Andean region.     

Smoke aerosols dispersion and transport from the 2013 New South Wales (Australia) bushfires

Environmental monitoring and modelling, especially in the regional context, has seen significant progress with the widely usage of satellite measurement in conjunction with local meteorological and air quality monitoring to understand the atmospheric dispersion and transport of air pollutants. This paper studies the application of these data and modelling tools to understand the environment effects of a major bushfire period in the state of New South Wales (NSW), Australia, in 2013. The bushfires have caused high pollution episodes at many sites in the greater Sydney metropolitan areas. The potential long-range transport of aerosols produced by bushfires to other region and states has been seen by regulators as a major concern. Using data and images collected from satellites, in addition to the results obtained from different simulations carried out using HYSPLIT trajectory model and a regional meteorological model called Conformal Cubic Atmospheric Model (CCAM), we were able to identify at least 2 days on which the smoke aerosols from bush fires in NSW has been transported at high altitude to the northern state of Queensland and the Coral Sea. As a result, widespread high particle concentration in South East Queensland including the Brisbane area, as measured by nearly all the air quality monitoring stations in this region, occurred on the day when the smoke aerosols intruded to lower altitude as indicated by the CALIOP (Cloud-Aerosol Lidar with Orthogonal Polarization) Lidar measurements on the CALIPSO (Cloud–Aerosol Lidar and Infrared Pathfinder Satellite Observation) satellite. The use of meteorological or air quality modelling to connect the ground-based measurements with satellite observations as shown in this study is useful to understand the pollutant transport due to bushfires and its impact on regional air quality.     

农田土壤镉生物有效性及暴露评估研究进展

随着工业化和城市化进程的发展,我国在农田土壤污染领域面临较大挑战,其中镉(Cd)为最优先控制元素之一。农田土壤Cd污染风险类型为健康风险,其主要暴露途径为经土壤-植物系统,并经膳食进入人体。在当前的土壤Cd风险评估中,一般不考虑生物有效性问题,这使得风险评价中实际暴露评估的不确定性普遍偏高。所以,近年来欧洲国家有许多研究者提出将生物有效性因素放在土壤污染物风险评价框架内。基于此,本文立足于农田系统,并从土壤、植物、污染物及环境因素等4个方面详细综述了农田土壤Cd生物有效性的影响因素及其作用机理。其次,分别综述了近年来土壤Cd生物有效性预测模型和土壤Cd膳食暴露评估模型研究进展。最后,分析了我国土壤重金属风险评价中存在的不足,并对农田土壤Cd暴露评估发展态势和研究方向进行了初步预测,以期为农田土壤Cd健康风险评估及安全基准研究提供一定参考。     

Contaminant characteristics and environmental risk assessment of heavy metals in the paddy soils from lead (Pb)-zinc (Zn) mining areas in Guangdong Province,South China

Environmental Science and Pollution Research - In November 2016, the total metal concentrations in nine representative locations in lead (Pb)-zinc (Zn) mining areas, located in Guangdong Province,...     

Proton exchange membrane fuel cell purge and fan control using a microcontroller

This study used Programmable System-on-Chip to make a fuel cell controller to manage the fuel cell operating environment. When a proton exchange membrane fuel cell is reacting, its performance is closely related to the operating conditions, such as temperature, water management, etc. This article investigates purge time interval control and the related characteristics. The controller developed in this study is free from additional power requirements, using only the power provided by the fuel cell.     

聚磷酸钙可降解纤维研究

为解决材料在环境中的降解问题,制备了聚磷酸钙纤维．研究表明其结构为无定形玻璃态,抗拉强度为１．９０ＧＰａ,弹性模量为６７．５ＧＰａ,并可发生化学降解,故可作为可降解复合材料的增强纤维     

填方边坡碎石填土配比优化研究

在我国黄土丘陵地区,每年因为高填方边坡失稳而造成的人员伤亡和财产损失数不胜数,有必要从高填方边坡的填料入手,开展高填方边坡失稳问题研究。以陕西某高填方边坡为例,将高填方边坡的碎石填料作为主要研究控制对象,取其边坡正在填筑的碎石填料,通过诸多室内试验测定物理力学参数、渗透性等,并借助FLAC 3D数值模拟计算其稳定性,先确定最优土石比,再确定在最优土石比下的优选级配。择优选择的级配相比之前的填料,力学性能更好,强度更高,隔水效果控制更明显,坡体的整体稳定性加强。从填方填料入手,能有效降低因回填材料不合理而引发的边坡失稳。     

Human PCDD/PCDF levels near a pentachlorophenol contamination site in Tainan, Taiwan

A pentachlorophenol (PCP) manufacturing plant in southern Taiwan discontinued production in 1989. The site of the abandoned plant was heavily contaminated by PCDD/PCDFs, impurities formed in the PCP production process. Serum samples collected from 27 residents living near the deserted plant were evaluated to determine whether this contamination had associated serum levels of PCDD/PCDFs in local residents. The average level of 17 tested congeners ranged from 556 to 5240 pg/g lipid (mean, 1670 pg/g lipid). The corresponding 2,3,7,8-TCDD toxicity equivalent quotient values calculated by international toxicity equivalent factors (I-TEFs) and those recommended by WHO (WHO-TEFs) were 47.2 pg I-TEQ/g lipid and 53.4 pg WHO-TEQ/g lipid, respectively. Levels in other parts of Taiwan typically range from 15 to 20 pg WHO-TEQ/g lipid; therefore, it is likely that the heavily contaminated plant site caused these unusually high serum levels. The average PCDD/PCDF levels of 29 fish-tissue and nine soil samples collected from the sea reservoir surrounding the abandoned PCP plant were also abnormally high: 8630 pg/g lipid (985 pg WHO-TEQ/g lipid) and 606000 pg/g-sample (922 pg WHO-TEQ/g-sample), respectively. Factor analysis indicated that the congener pattern of human serum samples collected from residents living near the abandoned PCP plant different from samples collected from other areas in Taiwan without known PCDD/PCDF pollution. Similar results were observed for the fish tissue and soil samples. The current study may have discovered a "hot spot" for elevated dioxin human exposure in Taiwan. The preliminary finding has raised a public health concern in the inspected area and requires further investigations to clarify the nature of the contamination and potential impact on the local environment and human health.