网状生物转盘-生物接触氧化法处理高浓度生活污水的实验研究

针对普通生物转盘生物量小,有机负荷低等特点,首次采用新型网状生物转盘辅以生物接触氧化技术联合处理城市生活污水,为提高其处理效果,分别考察了水力停留时间、转盘转速、气水比、有机负荷的研究对COD去除效果的影响。结果表明：网状生物转盘具有较强的抗冲击负荷的能力,实验中转盘的有机负荷为35.41 g COD/(m2·d)时,...     

中国不可再生能源消耗压力驱动与强度分解

随着煤炭、石油、天然气等不可再生能源的掠夺式开采的日益严重,中国不可再生能源供需缺口日渐放大,来自于经济增长和消耗强度的冲击使得中国不可再生能源消耗压力逐年增大.在对不可再生能源供需缺口以及消耗构成分析的基础上,运用IPAT方程、LMDI分解法,对中国不可再生能源消耗压力的驱动因素进行实证分析,针对作为主要驱动因素的不可再生能源消耗强度,运用费雪指数分解法进行二次结构、效率效应分解,并就分析结果作出具体剖析.研究结论如下:①中国不可再生能源消耗压力呈现“谷峰交替”型变动趋势,消耗压力的增加主要源于经济因素的驱动,消耗压力的减弱主要源于消耗强度的抑制性驱动作用;②结构效应指数对不可再生能源消耗强度的变动发挥主要影响作用,产业结构的低碳化调整会促进工业部门内部消耗强度的降低,从而达到拉动不可再生能源整体消耗强度降低的目标.     

Modeling short-term variability of semivolatile organic chemicals in air at a local scale: an integrated modeling approach

Monitoring campaigns from different locations have recently shown how air concentrations of persistent semivolatile contaminants such as polychlorinated biphenyls (PCBs) often exhibit short-term (less than 24 h) variations. The observed patterns have been ascribed to different factors, such as temperature-mediated air-surface exchange and variability of planetary boundary layer (PBL) height and dynamics. Here, we present a new modeling approach developed in order to investigate the short-term variability in air concentrations of organic pollutants at a local scale. A new dynamic multimedia box model is supplied by a meteorological preprocessor (AERMET) with hourly values of air compartment height and wind speed. The resulting model is tested against an existing dataset of PCB air concentrations measured in Zurich, Switzerland. Results show the importance of such modeling approach in elucidating the short- and long-term behavior of semivolatile contaminants in the air/soil system.     

Investigation of ZnO nanoparticles’ ecotoxicological effects towards different soil organisms

Introduction  

Nanomaterials have widespread applications in several industrial sectors. ZnO nanoparticles (NPs) are among the most commonly used metal oxide NPs in personal care products, coating and paints. However, their potential toxicological impact on the environment is largely unexplored.     

Phenanthrene sorption/desorption sequences provide new insight to explain high sorption coefficients in field studies

The sorption coefficients obtained in field investigation vary greatly from laboratory sorption experiments. The possible reasons were discussed in literature. Observing the commonly reported desorption hysteresis, this study proposed that the unclear sorption history of the field study could also result in the diverse sorption coefficients. This study conducted a comparative study regarding phenanthrene sorption/desorption behavior in low-concentration multi-time sorption process and the commonly applied high-concentration one-time sorption process. The sorption coefficients determined during the desorption process were much higher than those at sorption process. Thus, the prediction of sorption coefficient should be related with sorption history. Desorption hysteresis was increased with increased equilibration time and decreased solid-phase concentration. In addition, although the apparent contact time between sorbate and sorbent was shorter for low-concentration multi-time sorption, the desorption hysteresis was much stronger, which consequently result in higher sorption coefficients in comparison to high-concentration one-time sorption. Pore swelling or diffusion-controlled sorption kinetics could not explain this phenomenon. This study calls for research attention on sorption history, especially for field investigations.     

Toxicity and biodegradation of the LAS surfactant 1-(p-sulfophenyl)nonane in presence of the ascidian Styela plicata

The main objective of this study, within development of engineering solutions for coastal areas depuration, was to establish the role of the benthic macro-organisms in the biodegradation of the detergents in marine environment and to estimate the toxicity of these substances for a particular marine species: the ascidian Styela plicata. The experimental studies undertaken in aquarium with seawater enriched in a pure lynear alkylbenzene sulfonate (LAS), the 1-(p-sulfophenyl)nonane (1C9-LAS), showed that the degradation was two times more fast in presence of the S. plicata, than of the only marine bacteria. The toxicity of this pollutant was also determined. This study demonstrates that the ascidia S. plicata can be a potential biomediator for the surfactant 1C9-LAS, and it can be used to design a pilot project, to bioremediate harbours and the coastal areas interested from the urban pollution.     

北戴河空气负离子浓度测定与负离子评价标准

本文介绍了空气负离子及其在清洁空气、抗菌和卫生保健方面的作用,通过对北戴河地区六处景点的空气负离子浓度进行测定,制定了评价空气负离子浓度的七级评价标准体系,提出在充分利用自然环境中所形成空气负离子的卫生保健作用的同时,创制释放负离子纤维织物,制造随身携带的负离子发生器,构筑健康万里长城。     

单个药品及其混合物对Aliivibrio fischeri的毒性研究：单一化合物的实验结果，并对其行为机理和对水生生物潜在急性效应进行思考

在这个较广泛的关于单个和多组分混合药物活性化合物影响研究的第一部分,作者使用了Microtox^?测试系统详细分析了10种广泛使用的人用和兽用药活性化合物对生物荧光细菌Aliivibrio fischeri的影响。实验结果表明大多数受试化合物具有中度毒性。对比实验得到的50%抑制浓度和定量构效关系模型预测的结果表明,大多数受试药物活性化合物与极性麻醉型化合物对A. fischeri的行为类似(似乎只有抗生素金霉素有特定的作用机制)。将实验结果与其他不属预定目标的生物急性毒性数据集进行比较表明,一般而言A . fischeri较其他水生物种敏感。然而,根据全球化学品统一分类和标签制度,大部分受调查的化学物质可归为水生生态系统中有害或无毒的化合物。最后,基于欧盟水体中测量的环境浓度第95百分位数和各种水生生物的急性毒性数据的比较,可以认为当受试药物活性化合物作为单一化合物进行评估的时候,不存在水生生物风险。
精选自Valeria Di Nica, Sara Villa, Antonio Finizio. Toxicity of individual pharmaceuticals and their mixtures to Aliivibrio fischeri: experimental results for single compounds and considerations of their mechanisms of action and potential acute effects on aquatic organisms. Environmental Toxicology and Chemistry: Volume 36, Issue 3, pages 807–814, July 2017. DOI: 10.1002/etc.3568
详情请见http://onlinelibrary.wiley.com/wol1/doi/10.1002/etc.3568/full
     

基于Crowbar保护电路的双馈风电系统高电压穿越

针对电网电压发生骤升故障时造成的电网不稳定运行,在双馈机组转子侧加入Crowbar保护电路,增加双馈风电系统高电压穿越的能力。通过建立电网电压骤升时双馈风电机组投入Crowbar保护电路后的数学模型,并从磁链角度推导出转子侧暂态电流及其最大估算值,根据短路电流和直流侧母线耐受电压的大小,确定Crowbar电路串联的电阻值、切入和退出时间,加速系统暂态电流的衰减,实现双馈系统的高电压穿越。Matlab/Simulink仿真结果表明:控制方案增强了双馈发电系统稳定运行的可靠性,并提高了双馈风力发电系统的高电压穿越能力。     

Assessment of Ni accumulation capability by fungi for a possible approach to remove metals from soils and waters

ABSTRACT

Abandoned industrial sites and mines may constitute possible hazards for surrounding environment due to the presence of toxic compounds that may contaminate soils and waters. The possibility to remove metal contaminants, specifically nickel (Ni), by means of fungi was presented exploiting a set of fungal strains isolated from a Ligurian dismissed mine. The achieved results demonstrate the high Ni(II) tolerance, up to 500 mg Ni l^?1, and removal capability of a Trichoderma harzianum strain. This latter hyperaccumulates up to 11,000 mg Ni kg^?1, suggesting its possible use in a bioremediation protocol able to provide a sustainable reclamation of broad contaminated areas.