近距平行跑道配对进近碰撞风险评估

近距平行跑道实施配对进近可有效提高机场容量,解决机场拥挤和延误的问题。为保证航空器的安全运行,研究其水平碰撞风险,基于导航设备测量误差和速度偏差,建立配对进近前后两机的实际侧向距离和纵向距离基于速度、时间的方程,在此基础上建立近距平行跑道配对进近的碰撞风险评估模型,给出模型中相关参数的计算公式。最后通过Matlab软件对该模型进行计算,给出了随相关参数变化水平碰撞风险变化的曲线图,并验证了模型的合理性。     

基于发动机活动的集装箱港作机械排放清单研究

随着我国集装箱港口吞吐量持续增长,港区大气污染物排放亦日益增加,港作机械等非道路移动源排放更逐渐成为公众关注的焦点。借鉴OFFROAD模型的基本方法,通过调查分析集装箱港区作业机械的保有量、活动水平和设备参数等,修正排放因子,采用"自下而上"基于集装箱港作机械发动机活动水平的动力法建立集装箱港作机械大气污染物排放清单。并以南京港龙潭集装箱港区(NPLC)为案例,构建排放清单。结果表明:2014年NPLC港作机械排放总量为PM_(10) 4.25 t、PM_(2.5) 3.91 t、NO_x 82.98 t、SO_x 1.06 t、CO 23.84 t和HC16.39 t;集装箱拖车为最大排放贡献源,NO_x为高值排放污染物;与港区其他排放源相比,港作机械为颗粒物质(PM)与碳氢化合物(HC)的最大排放源。相较NPLC 2013年基于燃油消耗的研究,基于活动的排放量较低。     

基于信息熵的危险天气下进近管制风险评估

针对危险天气下进近管制系统运行风险性大、易发不安全事件的问题,提出根据一段时期内不安全事件的信息来评估该时期进近管制系统运行的风险,从而为以后进近管制系统的安全运行管理提供依据。首先,通过分析危险天气下管制系统运行过程的风险因素,建立风险评估指标体系。其次,给出评估指标灰色关联度属性的计算方法,利用其反映出的信息熵完成指标权重的确定和风险评估模型的建立。最后,应用该模型评估某进近管制中心一段时期内管制运行的风险状态水平,得到了风险值和风险级别,验证了该方法的适用性。     

芜湖市沉积物-水体PAHs扩散行为研究

为研究芜湖市不同功能区景观水体多环芳烃（PAHs）在沉积相-水相之间的扩散行为,于2017年2月选择芜湖市25处景观水体采集沉积物和水样品,对美国环保署（EPA）列为优先控制污染物的16种PAHs进行检测,运用逸度方法、响应系数进行分析.分别考虑有机碳（OC）、BC_CTO（化学热氧化法测定的黑碳）和BC_Cr（湿化学氧化法测定的黑碳）在不同浓度（实测值、最低值、平均值、最大值）情况下对PAHs在沉积相-水相间扩散的影响.结果表明,中低环（2~4环）PAHs表现出向水相扩散,沉积物作为PAHs的二次污染源,高环（5~6环）PAHs表现出向沉积相扩散,沉积物作为PAHs的汇;随着OC和黑碳（BC）含量的增加,PAHs倾向于向沉积相扩散,且倾向程度是BC_Cr > BC_CTO > OC,表明BC在PAHs的沉积物-水扩散过程中起重要的作用.响应系数结果表明中低环PAHs的逸度分数（ff）对OC、BC_CTO和BC_Cr浓度变化的敏感度较弱,高环PAHs的ff对OC、BC_CTO和BC_Cr浓度变化的敏感度较强,且敏感度强弱依次是BC_Cr > BC_CTO > OC.沉积相-水体的扩散过程研究揭示了PAHs在水环境中迁移扩散的重要机理,可为环境污染的科学治理提供依据.     

协议出让国有土地使用权最低价的确定方法

合理确定协议出让国有土地使用权的最低价,是促进经济与社会发展,防止土地资产流失的重要措施．本文以国家土地管理局的有关现定为依据,在阐述基准地价内涵、基准地价与国有土地使用权出让价相互关系的基础上,探讨了协议出让国有土地使用权最低价的具体确定方法,并将它初步应用在山西省祁县城区土地使用权协议出让最低限价的确定中．     

Ecotoxicity in Aliivibrio fischeri of Ibuprofen,Omeprazole and their Mixtures

The acute ecotoxic effects of ibuprofen and omeprazole and their mixture have been measured using Aliivibrio fischeri as a biomodel. The toxic effects were also tested after 5 days, and an effect-driven approach was used to analyse the results. The toxic effects of the mixtures were compared with the predictions obtained using concentration addition and independent action mathematical methods.

According to the Passino and Smith classification, the results indicate that ibuprofen can be considered slightly toxic (10<EC₅₀ <100?mg?L^-1), while omeprazole can be denoted as moderately toxic (1<EC₅₀ <10?mg?L^-1) to Aliivibrio fischeri. An overestimation of the actual ecotoxic effect of the mixture was found when the concentration addition and independent action methods were applied. Finally, the effect-driven approach indicated that the transformation products of the studied drugs should be prioritized for risk assessment purposes.     

热力学理论在湖泊富营养化研究中的应用

本文在分析了生态系统进化的热力学理论（最大能量、最大功率、最大优势原理）的基础上，综述了能量、功率和优势值在国内外湖泊富营养化研究中的应用，说明生态系统进化的热力学理论为认识和研究复杂的湖泊生态系统提供了整体性的途径，并指出为把热力学理论有效地用于湖泊富营养化的研究而应加强的科研工作。     

变电站及其线路建设工程项目公众参与的重要性探讨

变电站及其线路建设因其跨度大,涉及众多的乡镇村或苏木的村民的利益,为使工程建设达到可持续发展的目标,听取不同层次人员的意见,尤其是听取线路经过的乡、镇政府(苏木)中公务员以及拆迁房、迁坟和占耕地村民的意见,是环评工作中极为重要且必不可少的一个环节.以"500 kV高新变--德岭变送电线路工程项目"的公众参与与实践为例,对公众参与过程中所面临的一些普遍问题进行探讨.     

Evaluating the heavy metal contamination in sediments from the guadalquivir estuary after the Aznalcóllar mining spill (SW Spain): a multivariate analysis approach

The Doñana National Park is one of the most importantNatural Reserves in west Europe. The park and theGuadalquivir estuary were impacted by the release of 5million cubic meters of acid waste from the processing ofpyrite ore. Here are presented a multivariate analysisapproach to evaluate the extension and the magnitude of theaccidental spill on the estuarine sediments. Sediments wereused to analyze 6 different metals (Fe, Mn, Zn, Cd, Pb, Cu).Also the concentration of the metals in the differentgeochemical sediment fractions were determined as a means ofassessing the potential impact of the acid water from themine. The analysis of the results obtained permits toestablish that the impact of the accident was acute on theecosystem due to the set up of a treatment plan in June 1998and to the high hydrodynamic of the estuary that absorb theearly impact. Chronic contamination by Cu was also detectedduring the monitoring of the impact of the accident in theestuary but this did not appear to be related to theaccidental spill. Because the likelihood of long term adverseeffects from the heavy metal contamination of estuarinesediments, further ecotoxicological evaluations should becarried out for the estuary and the park using an integrated approach.     

Impact significance determination—Designing an approach

The question of how best to go about determining the significance of impacts has, to date, only been addressed in a partial and preliminary way. The assumption tends to be made that it is either only necessary to provide explicit, justified reasons for a judgment about significance and/or to explicitly apply a prescribed procedure—a procedure usually involving the staged application of thresholds and/or criteria. The detailed attributes, strengths and limitations of such approaches and possible alternative approaches have yet to be explored systematically.This article addresses these deficiencies by analyzing the characteristics, specific methods and positive and negative tendencies of three general impact significance determination approaches—the technical approach, the collaborative approach and the reasoned argumentation approach. A range of potential composite approaches are also described. With an enhanced understanding of these approaches, together with potential combinations, EIA practitioners and other EIA participants can be in a better position to select an approach appropriate to their needs, to reinforce the positive tendencies and offset the negative tendencies of the selected approach and to combine the best qualities of more than one approach.