三峡库区燃煤,土壤和水库底泥中含汞量分布特征

详细研究了长江三峡库区燃煤，土壤和沉积物中汞的分布特征，以及湖泊沉积物中不同形态汞的含量，探讨了水库汞污染加重原因。     

Influence of industry on the geochemical urban environment of Mieres (Spain) and associated health risk

This study is concerned with the elemental composition of soils and street dust collected in an historical industrial city of approximately 27 000 inhabitants, where old Hg mining and metallurgical activities strongly affected the load of heavy metals in the urban environment. For the purpose of the study, representative samples of soils and street dust were collected at different locations in the whole urban area (3 km²). Elevated mean concentrations of As in soils and street dust (69 and 135 g g^–1, respectively), and Hg (3.07 and 4.24 g g^–1, respectively), compared to background levels and to those found in other cities, reflect the anomalous geochemical nature of these materials and the strong influence exerted by the old mining sites.     

Steady Shallow-Water Current and Solute Transport around a Semi-Conical Headland

Laboratory experiments have been carried out to investigate the effects of a sloping wall headland on the flow characteristics and the associated concentration distributions from a point source around the headland. A semi-conical headland with a slope of 1:2 was set up in a flow basin, 4.8 m long and 3.8 m wide. In this paper, the experimental results of a steady shallow-water current are reported. Three dimensional flow velocities in the basin were measured using Sontek-ADV instrument. The dye concentration levels in the basin were measured by two fluorometers. The experimental results showed a large-scale re-circulation region behind the semi-conical headland. The peak turbulence energy, at about 53% of the local kinetic flow energy, coincides with the region of high velocity gradient. Significant vertical flows were observed around the area near the downhill slope of the headland, with a maximum ratio of vertical to horizontal velocities being about 22%. Such relatively significant vertical scouring velocities, coupled with strong turbulence energy and high horizontal velocity gradients in the same region, could cause severe bed erosion. The experimental results have also been compared with the predicted results of a depth-averaged numerical model. The predicted eddy structure and the concentration distribution in the re-circulation area were found to compare favourably with the experimental results. However, the discrepancies in the flow velocities and the concentration levels near the headland were apparent. It was observed that the dye concentration continued to spread in the cross-stream direction after passing the headland, whereas only a limited extent of the lateral spreading was predicted by the numerical model further downstream of the headland.     

散化码头化学品水污染危害性评估模式研究

提出散化码头三类典型液体化学品水污染危害性评估模式 ,并建立其计算扩散模型。     

深街道峡谷内高架桥对污染物传播特性影响的模拟研究

城市化进程导致在城市中出现通风条件较差的深街谷,建设于深街谷内的高架桥会加重周边街谷内空气污染.用计算流体力学模拟方法（CFD）探索在不同环境风速下的深街谷中,高架桥的高度和宽度对街谷内气流组织与污染物扩散的影响.结果表明:高架宽度小于0.8倍街谷宽度时的高架桥不会抑制桥下空间的流动;桥宽增加会改变桥下空间的涡旋结构和涡旋方向,近地面流动方向由之前的从右至左流动变为从左至右流动,因而桥下空间污染分布也发生明显改变;高架桥宽度的增加导致两侧低层住户受到较大影响,对背风面住户的影响更为明显;但高架宽度为0.5倍街谷宽度的高架桥能对迎风面中层住户造成影响;增加高架桥的高度,其下方污染物浓度增加;当高架桥位于街谷冠层时,下部空间的污染物浓度急剧增加;冠层处及涡旋交界面高架桥对两侧住户产生较大影响,而其他高度高架桥对两侧住户影响不大;随着环境风速的增加,高架桥对近地面源污染物扩散的阻碍作用逐渐减弱.研究显示,深街谷中增加高架桥的宽度、高度都会导致街谷内空气质量的恶化,而高架桥会阻碍因环境风速增加对街谷内空气质量的改善.      

矿井瓦斯爆炸高速气流的破坏和伤害特性研究

针对煤矿瓦斯爆炸事故频发现状,基于爆炸动力学、流体动力学理论对巷道受限空间瓦斯爆炸冲击波波阵面后高速气流的传播特性进行分析,建立高速气流压力和速度关系的数学模型。结合在实验巷道中瓦斯爆炸高速气流压力实验数据,拟合瓦斯爆炸高速气流速度和传播距离的计算公式,其结果表明,井下瓦斯爆炸事故高速气流的传播速度随传播距离的增加而减小。依据我国陆地地面风力等级划分标准比照可得瓦斯爆炸高速气流的等级为飓风级,对井下人员伤害巨大。该研究成果为控制和预防瓦斯爆炸破坏和伤害事故扩大及事故应急救援提供了理论依据。     

A Street Categorization Method to Study Urban Noise: The Valladolid (Spain) Study

Abstract We describe the application of a categorization method for road traffic noise (TN) evaluation. The method assumes that urban noise is stratified according to a five-category classification of streets based only on their use as communication routes. The method has previously been shown to be valid for towns under 220,000 inhabitants, and in the present case is applied to study the urban noise in Valladolid (Spain), a town with a population of nearly 320,000 inhabitants. Novel mathematical tools in this field are used to analyze the method. We demonstrate the existence of a stratification of the streets sound levels. Thus, the categories defined seem to be quite adequate for towns of this size range. Moreover, noise level predictive capacity of the method was also analyzed, and an overall value for the predictive capacity of 80% was obtained. Thus, our method can be a simple, low-cost strategy to make a statistical evaluation of the TN in a city.     

Hybridization,agency discretion,and implementation of the U.S. Endangered Species Act

The U.S. Endangered Species Act (ESA) requires that the “best available scientific and commercial data” be used to protect imperiled species from extinction and preserve biodiversity. However, it does not provide specific guidance on how to apply this mandate. Scientific data can be uncertain and controversial, particularly regarding species delineation and hybridization issues. The U.S. Fish and Wildlife Service (FWS) had an evolving hybrid policy to guide protection decisions for individuals of hybrid origin. Currently, this policy is in limbo because it resulted in several controversial conservation decisions in the past. Biologists from FWS must interpret and apply the best available science to their recommendations and likely use considerable discretion in making recommendations for what species to list, how to define those species, and how to recover them. We used semistructured interviews to collect data on FWS biologists’ use of discretion to make recommendations for listed species with hybridization issues. These biologists had a large amount of discretion to determine the best available science and how to interpret it but generally deferred to the scientific consensus on the taxonomic status of an organism. Respondents viewed hybridization primarily as a problem in the context of the ESA, although biologists who had experience with hybridization issues were more likely to describe it in more nuanced terms. Many interviewees expressed a desire to continue the current case‐by‐case approach for handling hybridization issues, but some wanted more guidance on procedures (i.e., a “flexible” hybrid policy). Field‐level information can provide critical insight into which policies are working (or not working) and why. The FWS biologists’ we interviewed had a high level of discretion, which greatly influenced ESA implementation, particularly in the context of hybridization.     

宝鸡市街道尘埃磁学特征空间分布及环境意义

对宝鸡市街道尘埃样品进行详细系统环境磁学实验分析并结合扫描电子显微镜研究表明,宝鸡市街道尘埃中磁性矿物含量高,主要的磁性矿物为多畴和假单畴的低矫顽力亚铁磁性矿物,同时含有少量的赤铁矿等高矫顽力的硬磁性矿物.污染来源主要以工业和交通等人为污染为主.街道尘埃的磁学特征表现出一定的空间变化规律揭示出污染的空间分布,划分为6个主要区域:A(创新路到高新八路区域)和B(东风路和马营路区域),磁性物质含量整体很高,揭示污染相对较重,污染源主要为"工业+交通";C区(火炬路到医康区域)磁性物质含量相对较高,是中度污染的区域,污染源主要为"交通";D(经二路与人民路区域)、E(清姜路和姜谭路西部区域)和F(陈仓区虢镇),磁性物质含量相对较低,揭示轻度污染,污染源主要为"交通".     

金华市街道灰尘磁化率时空变化研究

对不同时空条件下的金华市二环以内的街道灰尘样品的磁化率进行了研究.结果表明,金华市街道灰尘磁化率均值349.67×10-8 m3/kg,冬、春、夏各个季节的平均值:322.55×10-8 m3/kg、358.16×10-8 m3/kg和368.31×10-8 m3/kg,指示了其均具有磁性增强效应,且其值相近;春、夏两个季节街道灰尘磁化率的高值区分布结构相似,模型参数分析表明,区域因素为影响其值的主因;街道灰尘磁化率高值区与城区工业区大体吻合分布,工业区是主要的区域因素。