Utilization and degradation of imazaquin by a naturally occurring isolate of Arthrobacter crystallopoietes

A species of bacteria that is capable of utilizing imazaquin as the sole carbon source was isolated from soil with repeated imazaquin applications, and was identified as Arthrobacter crystallopoietes (designated as strain “WWX-1”). This isolate degrades imazaquin as high as 200 μg ml⁻¹, and the estimated dissipation half-lives increased from 1.51 d for the treatment at 50 μg ml⁻¹ to 4.75 d for 200 μg ml⁻¹. Optimal growth of WWX-1 in mineral salt medium with 50 μg ml⁻¹ imazaquin was obtained at 35 °C and a pH of 5.0. Growth of WWX-1 was also observed in mineral salt medium with the addition of other imidazolinone herbicides such as imazethapyr and imazapyr, but not with different classes of herbicides such as metsulfuron-methyl. Two imazaquin metabolites were detected, and spectral analysis with HPLC–MS, ¹H NMR, and IR revealed one metabolite with a molecular weight (MW) of 199 as quinoline-2,3-dicarboxylic anhydride. We propose that A. crystallopoietes (WWX-1) could serve as an efficient biodegradation system for remediation of water and soils that are heavily contaminated with imazaquin or other structurally similar chemicals.     

盐酸溶液改性蛭石对气态单质汞的吸附性能

采用盐酸溶液对蛭石进行浸渍处理，考察了盐酸溶液改性蛭石对气态单质汞的吸附能力。研究结果表明：盐酸溶液改性蛭石对气态单质汞的吸附效果好于未改性蛭石，盐酸浓度为4．0mol／L时，盐酸溶液改性蛭石对气态单质汞的吸附效果较佳；进气中气态单质汞的质量浓度越高，盐酸溶液改性蛭石对气态单质汞的去除率越低；适当提高吸附温度对盐酸溶液改性蛭石吸附气态单质汞较有利；降低蛭石粒径，盐酸溶液改性蛭石对气态单质汞的去除率提高。     

优势菌的筛选及其强化活性污泥好氧反硝化的研究

利用含活性污泥提取物的贫培养基筛选SBR系统中的好氧异养优势菌。结合自然温度（15～20℃）、延长培养时间等条件来提高菌群的可培养性。从SBR活性污泥系统中分离出5种细菌。4株去除COD优势菌，1株异养硝化细菌，能在好氧条件下实现对总氮的去除。反应池底采用边缘对称曝气，反应池内细菌在时间顺序和空间位置上循环经历好氧过程及微氧过程。将PVA铝盐法固定的细菌对反应器进行生物强化。结果显示，在好氧工艺的条件下，投加优势菌群后，与未加优势菌群的反应器相比，可以显著改善污泥的沉降性能，COD、NH₃-N和TN降解率显著提高，分别达到98%、97%和90%。生物强化作用明显，反应器内具有良好的好氧反硝化环境。     

社会和谐与可持续发展

本文运用系统科学原理阐释了社会和谐的内涵,指出社会和谐须以人与自然和谐为基础,以人与人之间的平等、友爱和同合作为表征,其构建与实现应遵从人类社会的演化规律,依赖予在把握人类社会需求演绎、协同人与自然关系的基础上推动生产力的高效有序发展和自然资源、生态环境的可持续支持.进而从可持续发展角度,提出了人与自然和谐的"双剩余理论",以揭示其间的供瓣枧理和协同准则;推导出了社会收益分配的相对公平系数,以衡量人与人公平要求下的社会和谐.针对国情和战略目标要求,提出了以加强小城镇建设为轴心的城市、小城镇与农村人流、物流、财流和信息流合理聚散的"三元结构"发展模式,以促进我国和谐社会的建设和可持续发展战略的有序实践.     

反硝化除磷菌驯化富集方式的探讨

以SBR反应器分别采用一段式和二段式培养方法对反硝化除磷菌进行了驯化富集.结果表明,一段式和二段式培养方法驯化完成后的活性污泥沉降性能均较好,污泥体积指数(SVI)分别约为60、50 mL/g,反硝化除磷菌占聚磷菌的比例达到了77%和71%.两种培养方法下反硝化除磷菌PO3-4-P去除率和脱氮率分别达到了97%和95%以上,缺氧结束时水中PO3-4-P质量浓度小于1 mg/L.驯化完成后污泥的含磷率最高达到了3.7%(质量分数).因此,采用一段式或二段式驯化方法均能实现反硝化除磷菌的有效富集.     

On Index System and Quantitative Assessment of Eco-cities： A Case Study on Urban Agglomeration of the Yangtze Delta

Urban agglomeration of the Yangtze Delta （UAYD）, one of the most developed regions of China, has witnessed an increasing prevalence in building ecological cities when the ecological cities are pursued by many modem cities, and great achievements have been made in this regard. It is inevitable, however, that certain problems exist during the construction of ecological city, which include but not limited to non-harmonious development of urban complex ecosystem, and the difficulty in quantifying eco-city construction or incomplete quantification in assessing the construction of present and future eco-city. Based on the analysis on social-economic conditions and regional conditions of the UAYD, this paper attempts to set up an index system of eco-cities combining with local characteristics, and to adopt the indices of eco-city, urban harmony, and eco-city colligate to evaluate the ecological level, urban harmonious development and eco-city construction of cities within the UAYD. Results indicate that among 15 cities in UAYD, Suzhou City ranks the highest in terms of eco-city construction, whereas Nantong ranks relatively lower; sustainable eco-city construction is possible only when cities are developed in every respect of harmony.     

Remobilization of polycyclic aromatic hydrocarbons during the resuspension of Yangtze River sediments using a particle entrainment simulator

Remobilization of 16 polycyclic aromatic hydrocarbons (PAHs) during sediment resuspension was investigated using a particle entrainment simulator at shear stress from 0.2 to 0.5Nm(-2), typical of the energy levels present in many tidally driven aquatic environments. The results suggested that desorption from the entrained particles was the primary source of dissolved PAHs. summation operatorPAHs concentrations in particles on volume normalization increased about four times. However, on mass weight basis, summation operatorPAHs concentrations decreased from 6039.74+/-138.28microgkg(-1) to 1665.39+/-112.26microgkg(-1). The same trend was observed for individual PAHs. Dissolved concentrations of PAHs demonstrated significant differences depending on molecular weight and applied shear. The distribution of PAHs between particle and water phase suggested that for three-ring PAHs, the amounts of PAHs in particles were higher than the predicted values during our experiments. This might be due to presence of another active sorbent.     

Industrial Cluster Upgradation of Regenerated Resources in Miluo City

With China's rapid economic growth, ecological construction and environmental protection become increasingly important. The regenerated resources industry is an effective way to solve problems, such as resources depletion, energy shortage, and pollution, and it also has strategic importance for the construction of a resource-conserving and environment-friendly society. The regenerated resources industry has been established in Miluo for long time, which includes a recycling system, a processing and utilization system, and a refuse decontamination system. An industrial cluster is in its early stage of development. In order to solve current problems, such as short industrial chain, low processing rate, and low added value, the industrial cluster should be dynamically upgraded by means of technology innovation, chain nucleus creation, and chain extension. We think the industrial cluster of regenerated resources will become a local brand for Miluo, from which other regions or cities will gain valuable experiences and inspirations.     

A directional passive air sampler for monitoring polycyclic aromatic hydrocarbons (PAHs) in air mass

A passive air sampler was developed for collecting polycyclic aromatic hydrocarbons (PAHs) in air mass from various directions. The airflow velocity within the sampler was assessed for its responses to ambient wind speed and direction. The sampler was examined for trapped particles, evaluated quantitatively for influence of airflow velocity and temperature on PAH uptake, examined for PAH uptake kinetics, calibrated against active sampling, and finally tested in the field. The airflow volume passing the sampler was linearly proportional to ambient wind speed and sensitive to wind direction. The uptake rate for an individual PAH was a function of airflow velocity, temperature and the octanol-air partitioning coefficient of the PAH. For all PAHs with more than two rings, the passive sampler operated in a linear uptake phase for three weeks. Different PAH concentrations were obtained in air masses from different directions in the field test.     

Modification of ferrite–manganese oxide sorbent by doping with cerium oxide

Fe–Mn oxide and Ce-doped Fe–Mn oxide sorbents were studied on the structural and desulfurization behavior in COS removal from syngas. The effects of cerium oxide on the Fe–Mn oxides have been investigated by XRD, BET, TPR, XPS and TEM methods. Analysis data show that the Ce-doped sorbent has larger specific surface area and better particles’ dispersion compared with non-modified Fe–Mn sorbent. The addition of Ce improves the reduction performance of Fe–Mn species. The desulfurization experiments show that the desulfurization activity of sorbent can be increased because of the promotion of the structural and redox properties by ceria doped. The Ce-doped sorbent can reduce COS from 15,000 ppmv to less than 0.1 ppmv at 325 °C and a space velocity of 1000 h⁻¹.