The plant-enhanced bio-cathode: Root exudates and microbial community for nitrogen removal

A plant bio-electrochemical system(PBES) was constructed for organic pollutant removal and power generation. The bio-cathode, composed of granular activated carbon(GAC), stainless wire mesh and a plant species(Triticum aestivum L.), was able to catalyze cathodic reactions without any requirement for aeration or power input. During the 60-day-long operation, an average voltage of 516 m V(1000 Ω) and maximum power density(Pmax) of 0.83 W/m~3 were obtained in the PBES. The total nitrogen removal and total organic carbon removal in the PBES were 85% and 97%, respectively. Microbial community analyses indicated that bacteria associated with power generation and organic removal were the predominant species in the bio-cathode, and plant-growth-promoting rhizobacteria were also found in the PBES. The results suggested that the coupling of plants with the GAC cathode may enhance the organicmatter degradation and energy generation from wastewater and therefore provide a new method for bio-cathode design and promote energy efficiency.     

植物净化空气中汞污染的研究

对上海市常见易生长的22种植物进行了现场采样测试，结果发现，瓜子黄杨、广玉兰、海桐、蚊母、墨西哥落叶杉及棕榈对汞蒸气具有很强的吸收富集能力及抗毒性能．然后采用富集能力最强的瓜子黄杨进行一系列试验，结果显示，汞浓度随接触瓜子黄杨时间的延长而降低，而瓜子黄杨叶片的汞含量随时间的延长而增加。根据吸汞实验，计算得瓜子黄杨叶面积的吸气速率为0.133m     

大港发电厂温排水对附近海域浮游动物影响研究

分别于2010年夏、冬季对大港发电厂温排水口附近海域浮游动物进行调查。结果表明:调查区浮游动物以桡足类和幼虫类占优势,群落结构相对稳定,但丰度明显低于渤海湾其他海区,种类组成、丰度和多样性指数具有夏季高于冬季、近岸低于远岸的时空变化特征。临近温排水口的TJHS1117站位的浮游动物群落物种数、丰度及多样性等在6个调查站位中都处于最低,可见温排水对浮游动物群落结构及平面分布有一定的影响。     

火电厂煤尘污染防治主要措施研究

文章通过对火电项目煤尘产生源的分析,根据北方地区社会、经济、环境现状,提出电厂储煤场及输煤系统煤尘的主要防治措施,从而为北方经济欠发达地区火电厂的煤尘污染防治提供一些参考依据,促进环境质量的改善.     

Plant uptake and dissipation of PBDEs in the soils of electronic waste recycling sites

Plant uptake and dissipation of weathered PBDEs in the soils of e-waste recycling sites were investigated in a greenhouse study. Eighteen PBDE congeners (tri- through deca-) were detected in the plant tissues. The proportion of lower brominated PBDEs (mono- through hexa-) in plant roots was higher than that in the soils. A concentration gradient was observed of PBDEs in plants with the highest concentrations in the roots followed by the stems and lowest in the leaves. Reduction rates of the total PBDEs in the soils ranged from 13.3 to 21.7% after plant harvest and lower brominated PBDEs were associated with a higher tendency to dissipate than the higher brominated PBDEs. This study provides the first evidence for plant uptake of weathered PBDEs in the soils of e-waste recycling sites and planting contributes to the removal of PBDEs in e-waste contaminated soils.     

Debrominated, hydroxylated and methoxylated metabolism in maize (Zea mays L.) exposed to lesser polybrominated diphenyl ethers (PBDEs)

A hydroponic experiment was conducted to investigate the debrominated, hydroxylated and methoxylated metabolism of polybrominated diphenyl ethers (PBDEs, BDE-15, -28 and -47) in maize. A total of six debrominated metabolites (de-PBDEs), seven hydroxylated PBDEs (OH-PBDEs, including two unidentified OH-di-PBDEs and one unidentified OH-tri-PBDE) and four methoxylated PBDEs (MeO-PBDEs) were determined in the exposed plants. The metabolic products were detected in maize only after 12 h of exposure to the PBDEs. However, the concentration of each type of the metabolites (de-PBDEs, OH-PBDEs or MeO-PBDEs) decreased at the later exposure time, possibly due to further metabolism. The removal of a bromine atom or the introduction of a hydroxyl/methoxy group was easier at the ortho-positions on the biphenyl structure than at the para-positions. Concentration ratios of the total debrominated, hydroxylated or methoxylated metabolites to the parent congener (BDE-28 or -47) generally followed the order of leaves > stems ? roots, and MeO-PBDEs > de-PBDEs ? OH-PBDEs. These results suggest that metabolism occurred preferentially in leaves and stems than in roots. Less transformation and shorter elimination half-life of OH-PBDEs would contribute to the lower concentrations of OH-PBDEs than of de-PBDEs or MeO-PBDEs in maize.