Assessment of Ecological Risks at Former Landfill Site Using TRIAD Procedure and Multicriteria Analysis

Old industrial landfills are important sources of environmental contamination in Europe, including Finland. In this study, we demonstrated the combination of TRIAD procedure, multicriteria decision analysis (MCDA), and statistical Monte Carlo analysis for assessing the risks to terrestrial biota in a former landfill site contaminated by petroleum hydrocarbons (PHCs) and metals. First, we generated hazard quotients by dividing the concentrations of metals and PHCs in soil by the corresponding risk‐based ecological benchmarks. Then we conducted ecotoxicity tests using five plant species, earthworms, and potworms, and determined the abundance and diversity of soil invertebrates from additional samples. We aggregated the results in accordance to the methods used in the TRIAD procedure, conducted rating of the assessment methods based on their performance in terms of specific criteria, and weighted the criteria using two alternative weighting techniques to produce performance scores for each method. We faced problems in using the TRIAD procedure, for example, the results from the animal counts had to be excluded from the calculation of integrated risk estimates (IREs) because our reference soil sample showed the lowest biodiversity and abundance of soil animals. In addition, hormesis hampered the use of the results from the ecotoxicity tests. The final probabilistic IREs imply significant risks at all sampling locations. Although linking MCDA with TRIAD provided a useful means to study and consider the performance of the alternative methods in predicting ecological risks, some uncertainties involved still remained outside the quantitative analysis.     

Comparative Study of Predictive Computational Models for Nanoparticle‐Induced Cytotoxicity

With the increasing use of nanomaterials incorporated into consumer products, there is a need for developing approaches to establish “quantitative structure‐activity relationships” (QSARs). These relationships could be used to predict various biological responses after exposure to nanomaterials for the purposes of risk analysis. This risk analysis is applicable to manufacturers of nanomaterials in an effort to determine potential hazards. Because metal oxide materials are some of the most widely applicable and studied nanoparticle types for incorporation into cosmetics, food packaging, and paints and coatings, we focused on comparing different approaches for establishing QSARs for this class of materials. Metal oxide nanoparticles are believed, by some, to cause alterations in cellular function due to their size and/or surface area. Others have said that these nanomaterials, because of the oxidized state of the metal, do not induce stress in biological tests systems. This controversy highlights the need to systematically develop structure‐activity relationships (i.e., the relationship between physicochemical features to the cellular responses) and tools for predicting potential biological effects after a metal oxide nanomaterial exposure. Here, we attempt to identify a set of properties of two specific metal oxide nanomaterials—TiO₂ and ZnO—that could be used to characterize and predict the induced cellular membrane damage of immortalized human lung epithelial cells. We adopt a mathematical modeling approach that uses the engineered nanomaterial size characterized as a dry nanopowder and the nanomaterial behavior in ultrapure water, phosphate buffer, and cell culture media to predict nanomaterial‐induced cellular membrane damage (via lactate dehydrogenase release). Results of these studies provide insights on how engineered nanomaterial features influence cellular responses and thereby outline possible approaches for developing and applying predictive computational models for biological responses caused by exposure to nanomaterials.     

环境监管体制的审视:从重金属污染的角度

严峻的环境形势下,重金属污染仿佛压垮环境监管的最后一根稻草.基于对A县的微观分析,可以发现职责虚化与协调障碍是环境健康监管体制的首要问题,单一薄弱的监管手段是环境健康监管体制的重要问题.为此,提出整合性监管的研究范式,强调:环境监管工具的协同与整合,环境监管各阶段的协同与整合,各环境监管机构的协同与整合,监管式执法与公众参与执法的协同与整合,宏观治理措施与微观治理措施的协同与整合.     

金属熔化热与熔点的关系

本文改进了计算金属熔化热的经验公式,所得结果较前人方法更接近实验值,且反映了各种金属的熔化熵并非恒定不变而与其熔点有关的事实。     

表外筹资对利益关系人利弊的探讨

就表外筹资对各利益关系人的影响进行专门分析 ,旨在对这种方式予以充分认识并在企业筹资过程中加以合理的应用。     

宋代通货膨胀问题辨析--兼论宋代纸币的性质

宋代是人类历史上首次大规模发行纸币的时代 ,由纸币、金属货币和有价证券共同构成的宋代货币体系 ,其相互关系的复杂及其不确定性导致了宋代通货膨胀的复杂和持久 ,也造成了对这一问题看法上的诸种分歧和不足。事实上 ,宋代正当中国古代社会经济大转型时期 ,其通胀成因错综复杂 ,表现出混合型的特征。宋代纸币是一种混合货币     

VF与Excel结合制作复杂报表

论述了在VF中利用COM技术编程 ,使我们的应用程序可以和EXCEL有机的组合起来 ,进而为用户提供强大的数据处理与报表打印系统     

Effect of Particle Size on Risk Assessment of Direct Soil Ingestion and Metals Adhered to Children's Hands at Playgrounds

The quantity of heavy metals in soil is measured after 2‐mm sieving in Japan for risk assessment of direct soil ingestion. A study was conducted on the relationship between the size of soil particles and quantity of heavy metals in soil, and the particle‐size distribution of soil adhered to children's hands, and the risks of direct intake of soil considering the particle sizes ingested were evaluated. The results showed that smaller particles had a tendency to contain more heavy metals than bigger ones, that the particle size of approximately 90% of the soil particles from playgrounds adhered to children's hands was less than 100 μm, and that 2‐mm sieving in preparation for measuring heavy metal content caused underestimation of the risk of direct soil intake. The amount of heavy metals on children's hands after playing outside was investigated. Various metals and soil were adhered to their hands, and the amount of soil adhered could be estimated from the concentration of metals. To develop accurate risk assessment, the particle‐size distribution of ingested soil and more detailed scenarios of soil intake are necessary.     

遗传算法优化的神经网络熔深预测模型

依据熔化极气体保护焊(GMAW)焊接时对焊缝熔深的影响因素,结合遗传算法,建立以焊接电流、焊接电压、焊接速度和焊缝熔宽为输入、以熔深为输出的BP神经网络焊缝熔深预测模型。仿真试验和结果分析表明：使用遗传算法能得到神经网络较好的初始权值和阈值,能显著提高网络性能;所建模型符合已有的焊接熔深理论研究,并且预测误差较小,具有较好的泛比能力和较高的预测准确性,对工程实际具有一定的指导意义。     

不锈钢真空钎焊管板连接微观特征及残余应力有限元分析

采用拉伸试验机对304不锈钢管板结构真空钎焊强度进行了试验,运用金相和EDS方法分析了钎焊接头的微观组织特征。运用有限元ANSYS软件对微小尺寸不锈钢管板结构在真空钎焊过程中产生的残余应力进行了模拟。结果表明,应力集中出现在管板连接钎焊接头处,有限元分析获得了该处的残余应力分布规律。