黄土高原生态化油田建设

针对长庆油田在黄土高原较为脆弱的生态环境下,建设西部大庆过程中所面临的油田快速发展与生态保护之间的矛盾,运用工业生态学原理,总结探讨了长庆油田以企业文化、数字化油田、集约用地、研究配套实用勘探开发技术、体制机制改革、发展循环经济及管理创新等手段对建设生态化油田进行探索,实现企业发展、生态保护、企地和谐,通过油田的开发改善和促进黄土高原的生态文明。     

Nano-TiO2 enhances the toxicity of copper in natural water to Daphnia magna

The acute toxicity of engineered nanoparticles (NPs) in aquatic environments at high concentrations has been well-established. This study demonstrates that, at a concentration generally considered to be safe in the environment, nano-TiO₂ remarkably enhanced the toxicity of copper to Daphnia magna by increasing the copper bioaccumulation. Specifically, at 2 mg L⁻¹ nano-TiO₂, the (LC₅₀) of Cu²⁺ concentration observed to kill half the population, decreased from 111 μg L⁻¹ to 42 μg L⁻¹. Correspondingly, the level of metallothionein decreased from 135 μg g⁻¹ wet weight to 99 μg g⁻¹ wet weight at a Cu²⁺ level of 100 μg L⁻¹. The copper was found to be adsorbed onto the nano-TiO₂, and ingested and accumulated in the animals, thereby causing toxic injury. The nano-TiO₂ may compete for free copper ions with sulfhydryl groups, causing the inhibition of the detoxification by metallothioneins.     

镇江滨江带湿地修复对浮游生物群落结构的影响

在镇江滨江带50 m×50 m的开放性湿地内进行实验,通过构建高位湿地、架设植物浮巢来改善滨江带湿地生境梯度和生境异质性,营造适宜各类士著动植物生长发育的湿地环境,从而达到增强生态系统延展性及增加生物多样性的目的.结果表明,高位湿地的构建、植物浮巢的架设等生态修复措施对提高研究区浮游植物、浮游动物群落的生物多样性有着显...     

Analysis of surface and aerosol polarized reflectance for aerosol retrievals from polarized remote sensing in PRD urban region

A precise estimate of polarization induced by surface is crucial for polarized remote sensing dedicated to monitoring aerosol properties over urban area. The accurate knowledge of interaction between surface and aerosol polarized reflectance is essential for accurately achieving aerosol properties. In order to study surface and aerosol polarized reflectance for aerosol retrievals over urban area, a new airborne directional polarimetric camera (DPC) with high spatial resolution (4 m at 4000 m a.g.l) was developed. The surface polarized reflectance over distinct surface covers of urban area (forest, shrub, and soil) were studied using DPC measurements during a field campaign in the Pearl River Delta (PRD), China. The large variations were found in surface polarized reflectance of distinct urban covers due to surface type variability. For all surface types, the empirical BPDF model cannot describe accurately surface polarized reflectance at all possible illumination and observation geometries. From the quantitatively study of relationship between surface and aerosol polarized contribution to DPC measurements, we show that the polarized contributions of aerosol, which optical properties were defined by ground-based measurements, are much larger than the polarized contribution of surface, and found that the polarized contribution of surface covers increases with decreasing NDVI. The effect of polarization accuracy of measurements on aerosol retrieval was also investigated using DPC measurements, and found that 0.1% polarization accuracy of measurements can be neglected when AOD is retrieved using polarized measurements. Based on the information of effects of polarized reflectance differences between distinct surface covers and polarization accuracy of polarized measurements on retrieved aerosols over urban area, we found that the accuracy of aerosol retrieval over forest covers is higher than other surface types using polarized remote sensing.     

固定化对氯苯酚降解菌在生物流化床中的降解特性

为了获得固定化对氯苯酚降解菌在生物流化床中的降解特性,用海藻酸钠-壳聚糖-活性炭微胶囊对实验室保存的对氯苯酚降解菌株进行固定化,在生物流化床中用固定化菌株在不同单因素实验条件下降解对氯苯酚废水,用气相色谱仪测定废水中对氯苯酚的降解率.结果表明,固定化对氯苯酚降解菌株处理污水的适宜条件为:HRT为72 h,微胶囊接种体积...     

微孔分布器对光催化臭氧氧化反应器传质的影响

为了开发高效的光催化臭氧氧化反应器,以不同孔径钛微孔气体分布器对臭氧气液传质性能进行了研究.考察了表观气速和表观液速对液相总传质系数的变化影响规律,获得了液相总传质系数与表观气速的关联公式和微孔板孔径与表观气速对液相总传质系数的经验关联公式.利用无因次吸收数对微孔分布器的性能进行了分析,得到不同表观气速下微孔分布器的性...     

分层式潜流人工湿地水力学特性数值模拟与分析

人工湿地水力学特征对其污染物去除过程有重要影响.采用计算流体力学软件FLUENT中的多孔介质模型对分层式潜流人工湿地内部的流场进行模拟,并分析了不同进出口位置对湿地水力学行为的影响.模拟结果表明,分层式潜流人工湿地基质层内部速度分布的差异较大,水流多从进口端的左半部汇人下部砾石层以大于3.69×10-4m/s的速度出流...     

1，2-二氯苯在3种基质中的吸附研究

采用平衡振荡法研究了1,2-二氯苯在3种人工湿地基质中的吸附情况。结果表明,1,2-二氯苯在12 h达到吸附平衡,可由Lagergren一级吸附动力学模型得出3种土壤的吸附速率常数分别为0.3338 h-1、0.2679 h-1和0.2537 h-1,壤土的吸附效果明显好于细砂、粗砂。30℃的吸附等温线既符合Freud...     

间二硝基苯清洁生产工艺研究

根据清洁生产原理、间二硝基苯生产工艺及废水产生情况,提出了重结晶废水直接回用于精制,精制废水蒸馏后回用于精制洗涤和重结晶的清洁生产工艺;经小试4次和中试3次废水循环套用后产品均为优等品,证明清洁生产工艺对产品质量无不良影响,可实现工艺废水零排放。     

Mercury species of sediment and fish in freshwater fish ponds around the Pearl River Delta, PR China: human health risk assessment

This study investigated total mercury (THg) and methylmercury (MeHg) concentrations in five species of freshwater fish and their associated fish pond sediments collected from 18 freshwater fish ponds around the Pearl River Delta (PRD). The concentrations of THg and MeHg in fish pond surface sediments were 33.1-386 ng g(-1) dry wt and 0.18-1.25 ng g(-1) dry wt, respectively. The age of ponds affected the surface sediment MeHg concentration. The vertical distribution of MeHg in sediment cores showed that MeHg concentrations decreased with increasing depth in the top 10 cm. In addition, a significant correlation was observed between %MeHg and DNA from Desulfovibrionacaea or Desulfobulbus (p<0.05) in sediment cores. Concentrations of THg and MeHg in fish muscles ranged from 7.43-76.7 to 5.93-76.1 ng g(-1) wet wt, respectively, with significant linear relationships (r=0.97, p<0.01, n=122) observed between THg and MeHg levels in fish. A significant correlation between THg concentrations in fish (herbivorous: r=0.71, p<0.05, n=7; carnivorous: r=0.77, p<0.05, n=11) and corresponding sediments was also obtained. Risk assessment indicated that the consumption of largemouth bass and mandarin fish would result in higher estimated daily intakes (EDIs) of MeHg than reference dose (RfD) for both adults and children.