污水处理厂中全氟化合物的污染研究

为研究全氟化合物在污水厂中的去除效率和环境行为,对泰安市2座污水处理厂进出水中不同链长的全氟磺酸和全氟羧酸的存在与分布进行了采样调查,并分析了全氟辛烷磺酸(PFOS)和全氟辛烷羧酸(PFOA)在采用曝气-A2O工艺的污水处理厂各单位中的浓度变化情况.研究发现,上述污水厂进出水中全氟化合物的污染程度较轻,其中,PFOA、...     

Degradation of Populus euphratica community in the lower reaches of the Tarim River, Xinjiang, China

IntroductionRiparian systems are aquatic-terrestrial ecotones withunique biotic , biophysical and landscape characteristics(Gregory, 1991 ; Naiman, 1997 ; Wiens , 2002) and areshaped by fluvial geomorphic processes . Riparian plantcommunities perform an i…     

基于模拟植物生长算法的快线公共车辆优化调度研究

公共车辆的运营优化调度能够很好的减少城市交通拥堵,缓解交通压力,保证多方面的利益。对乘客高峰期快线公共车辆的调度进行了研究。首先运用了三元组α/β/γ方法对问题进行了描述,将乘客高峰期快线车辆的调度描述为一类以最小化制造期和平均等待时间为目标,具有先入先出原则和机器适用限制的流水车间动态调度问题。并在此基础上建立了相应的数学模型;接着,运用模拟植物生长算法进行了算法设计;最后,用实际数据进行了数值仿真,结果证明该研究具有较高的理论及现实价值。     

黄土丘陵区坡面水蚀对降雨和下垫面微观格局的响应

黄土高原严重的土壤侵蚀是降雨和复杂脆弱的下垫面共同作用的结果.以微型小区尺度上(1.2 m×1.2 m;2 m×1.2m)模拟降雨技术为基本研究手段,定量刻画了降雨量和降雨强度等基本降雨特征值对定西安家沟自然坡面上荒草、沙棘中位、沙棘下位、沙棘上位、结皮裸地和裸地等不同植株微观格局及其处理下的水蚀过程的影响.主要取得以下结果:①雨强和雨量对水蚀的发生均能产生显著影响,但以雨强的影响力更大;②前期土壤含水量与产流时间显著负相关,而与径流量和侵蚀量显著正相关.前期含水量相同时,不同植株微景观格局对产流时间发挥了关键作用;③不同植株及其微观格局遏制地表径流的能力迥异.在50～60 mm.h-1的大雨强作用下,有沙棘覆盖的小区径流系数仅为5%～8%,荒草地为25%,结皮裸地为45%,而裸地则高达63%;④有沙棘覆盖的小区中,沙棘在小区中所处的具体位置对于水土流失效应又极为重要,以沙棘下位的水土保持效果最好.     

钢筋混凝土旧工业厂房主体结构的改造加固风险研究

为探索钢筋混凝土旧工业厂房的改造与加固风险,进行了实地调研和基础理论研究,借助SPSS 22.0统计软件对32个二级指标进行筛选,确立6个方面29个指标的改造加固风险评价指标体系,运用结构方程模型（SEM）实证分析关键影响因素及其作用路径。研究结果表明:设计方案、结构特征和施工技术对改造加固风险具有影响;结构特征与设计方案之间的强关联形成了隐性且重要的风险路径。基于关键影响因素及因素间关联关系,对宝鸡市某U型厂房主体结构加固实例提出建议,为此类项目的改造施工提供理论依据。     

持续淹水和干湿交替预培养对2种水稻土中Cd形态分配及高丹草Cd吸收的影响

采用盆栽试验的方法,研究了前期持续淹水和干湿交替预培养对2种水稻土———太湖地区黄泥土、江西鹰潭红壤性水稻土中外源Cd形态分配及高丹草吸收Cd的影响.结果表明,在5mg·kg^-1和10mg·kg^-1外源Cd处理下,与干湿交替预培养比较,持续淹水预培养后黄泥土中MgCl₂提取态Cd分别由21.8%、28.5%下降为8.0%、16.9%,而NH₂OH.HCl提取态Cd由17.7%、17.3%升高为28.1%、37.5%;红壤性水稻土NaAc提取态Cd由20.8%、29.6%下降为11.6%、12.6%.回归分析表明,MgCl₂提取态Cd与高丹草Cd吸收量呈显著负相关关系.长期淹水预培养显著降低高丹草对黄泥土Cd的吸收.     

典型燃煤电厂机组二氧化碳排放测试及核算研究

为验证二氧化碳排放量的测试技术适用性及可行性,获取燃煤电厂机组碳排放特征,系统比较不同测试方法之间碳排放量的差异,对某典型火电机组二氧化碳排放开展测试,结果表明,不同测试原理及设备二氧化碳排放实测体积分数均较为接近。测试机组CO₂实测体积分数为11.28%～14.21%,与负荷变化呈一定的正相关关系,不同负荷下基准氧含量(体积分数6%)基本无变化。测试机组排放量与负荷正相关,使用了缺省值的指南排放量最高,与其他方法排放量相对偏差均值为31.6%;使用入炉煤实测数据的指南排放量差异不大,相对偏差为0.1%;使用入炉煤实测数据的2版指南排放量高于直接测量法,相对偏差均值为4.9%;直接测量各类方法间相对偏差均值为1.0%,其中在线法与手工法间相对偏差均值为1.2%。CO₂排放强度与负荷负相关,实验条件下,机组负荷越高,碳排放强度越低。     

辽宁省菱镁矿区生态修复研究

针对辽宁省菱镁矿区资源状况与环境问题,提出菱镁矿区土地生态修复技术对策,包括土壤污染等级分类对策、不同立地条件土地复垦适宜性评价与对策、板结土壤复垦技术与对策和排土场贫瘠土壤肥力改良修复对策,进行适宜性复垦植物筛选与复垦效果评价。     

Lysimeter Experiments to Investigate the Fate of Chemicals in Soils – Comparison of Five Different Lysimeter Systems

Several lysimeter scenarios and approaches exist to study the fate of agro-chemicals or contaminants from deposition in soil columns. In many systems just transport and leaching of the parent compound is followed, in some systems the leaching and transport of the metabolites is investigated as well. In more sophisticated lysimeter systems the volatilization and also the mineralization of the applied chemicals can be additionally monitored. Depending on the lysimeter system used and on the fact whether the applied chemicals are ¹⁴C-labeled or not, different results and various interpretations of the results might be achieved. Different lysimeter systems are described in this paper and a real dataset of a specific lysimeter experiment was transferred and evaluated in a virtual approach in the different lysimeter systems in order to show the advantages and disadvantages of the various systems.     

CO2 emission driving forces and corresponding mitigation strategies under low-carbon economy mode: evidence from China’s Beijing–Tianjin–Hebei region

On account of the background of China’s “new normal” characterized by slower economic growth, this paper analyses the low-carbon economy status quo in the Beijing–Tianjin–Hebei region and empirically investigates the relationship between carbon dioxide (CO₂) emissions and its various factors for China’s Beijing–Tianjin–Hebei region using panel data econometric technique. We find evidence of existence of Environmental Kuznets Curve. Results also show that economic scale, industrial structure, and urbanization rate are crucial factors to promote CO₂ emissions. However, technological progress, especially the domestic independent research and development, plays a key role in CO₂ emissions abatement. Next, we further analyze the correlation between each subregion and various factors according to Grey Relation Analysis. Thereby, our findings provide important implications for policymakers in air pollution control and CO₂ emissions reduction for this region.