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Fe(Ⅲ)-EDTA作为阴极电子穿梭体的微生物燃料电池持续产电机制 总被引:1,自引:0,他引:1
阴极氧还原反应(ORR)是影响微生物燃料电池(microbial fuel cell,MFC)性能的重要因素.采用双室MFC以Fe(Ⅲ)-EDTA为阴极液进行持续产电试验.结果表明,添加Fe(Ⅲ)-EDTA作为阴极液可显著加速氧还原反应速率,降低内阻,提高输出电压与功率.当阴极液中存在20.0 mmol/L的Fe(Ⅲ)-EDTA时,电池内阻仅为300 Ω,比对照降低了900 Ω,其输出电压(1 000 Ω下)与功率密度可维持在200.1 mV、 16.0 mW/m2左右,比不加的对照分别提高73.2%、 70.1%. Fe(Ⅲ)-EDTA氧化再生与持续产电试验表明,Fe(Ⅲ)-EDTA可通过曝气氧化再生、循环利用,即Fe(Ⅲ)-EDTA可作为阴极电子穿梭体加速电子至氧气的传递.Fe(Ⅲ)-EDTA首先接受阴极电子被还原成Fe(Ⅱ)-EDTA,在阴极室充分曝气条件下,Fe(Ⅱ)-EDTA将电子传递给O2同时被氧化再生成Fe(Ⅲ)-EDTA,从而完成电子从电极传递到氧气的穿梭过程,MFC得以长期稳定运行.进一步优化试验显示,Fe(Ⅲ)-EDTA作为阴极电子穿梭体强化MFC产电的适宜条件为:浓度20.0 mmol/L、pH=5.0左右.在此条件下MFC的最大功率密度达100.9 mW/m2. 相似文献
344.
Removal of metals by sorghum plants from contaminated land 总被引:3,自引:0,他引:3
ZHUANG Ping SHU Wensheng LI Zhian LIAO Bin LI Jintian SHAO Jingsong 《环境科学学报(英文版)》2009,21(10):1432-1437
The growth of high biomass crops facilitated by optimal of agronomic practices has been considered as an alternative to phytoremediation of soils contaminated by heavy metals. A field trial was carried out to evaluate the phytoextraction efficiency of heavy metals by three varieties of sweet sorghum (Sorghum biocolor L.), a high biomass energy plant. Ethylene diamine tetraacetate (EDTA), ammonium nitrate (NH4NO3) and ammonium sulphate ((NH4)2SO4) were tested for their abilities to enhance the removal of heavy metals Pb, Cd, Zn, and Cu by sweet sorghum from a contaminated agricultural soil. Sorghum plants always achieved the greatest removal of Pb by leaves and the greatest removal of Cd, Zn and Cu by stems. There was no significant difference among the Keller, Rio and Mray varieties of sweet sorghums in accumulating heavy metals. EDTA treatment was more efficient than ammonium nitrate and ammonium sulphate in promoting Pb accumulation in sweet sorghum from the contaminated agricultural soil. The application of ammonium nitrate and ammonium sulphate increased the accumulation of both Zn and Cd in roots of sorghum plants. Results from this study suggest that cropping of sorghum plants facilitated by agronomic practices may be a sustainable technique for partial decontamination of heavy metal contaminated soils. 相似文献
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Hongliang Jia Liyan Liu Yeqing Sun Daoji Cai Jianxin Hu Nanqi Ren Yifan Li 《Frontiers of Environmental Science & Engineering in China》2012,6(1):32-44
This paper reviews the usage and emissions of endosulfan, the newest member of the persistent organic pollutants (POPs), in
China, and its fate and behavior in Chinese environment. Endosulfan usage in China has been estimated to be approximately
25700 t between 1994 and 2004. Concentrations of endosulfan in different environmental compartments in China, such as air,
soil, water, and biota, but focusing at air and surface soil, have been summarized. Concentrations of total endosulfan in
surface soil across China were ranged from below detection limit (BDL) to 19000 pg·g−1 dry weight (dw), with geometric mean of 120 pg·g−1dw. The results indicated that endosulfan sulfate had highest concentration in Chinese soil, followed by β- and α-endosulfan.
Air concentrations of endosulfan in China were ranged 0–340 pg·m−3 for α-endosulfan and 0–121 pg·m−3 for β-endosulfan, with high concentrations occurred in the cotton production areas. Gridded usage inventories of endosulfan
on a fine gridded system with a 1/4° longitude by 1/6° latitude resolution were compiled, from which, emission to air and
residues in soil of endosulfan were calculated in each grid by using a modified simplified gridded pesticide emission and
residue model (SGPERM), an integrated modeling system combining mathematical model, database management system, and geographic
information system. Total emissions were around 10800 t from 1994 to 2004. Based on the emission and residue inventories,
concentrations of α- and β-endosulfan in Chinese air and agricultural surface soil were also calculated for each grid cell,
which are in general consistent with the published monitoring data. 相似文献
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348.
采用大型通用有限元程序,对低硬度大直径橡胶隔震支座在竖向荷载作用下的基本性能进行了精细有限元分析.分析了在竖向荷载作用下支座上下封板、内部钢板的各种应力分布,以及支座顶部是否施加竖向同位移约束、支座孔径比、橡胶材料G值、内部单层橡胶厚度与内部单层钢板厚度之比对支座内钢板受力的影响.结果表明,内部钢板最大Mises应力、... 相似文献
349.
目前针对于基础隔震结构的性态水平研究往往基于刚性地基假设,未考虑 SSI 效应对结构损伤的影响。因此,为研究柔性地基上小高宽比基础隔震结构的抗震性态水平,本文以拟建结构为背景,利用 ABAQUS 有限元软件建立该小高宽比基础隔震结构建筑物的有限元计算模型,依据相关规范规定,选取 El?Centro 波、Kobe 波和卧龙波,通过改变土体等效剪切波速设计扩展出 5 种场地,分析了地震动特性、场地条件以及输入地震动加速度峰值对该结构地震反应的影响规律,对该结构的损伤程度进行了统计分析。结果表明:柔性地基上随结构?土体相对刚度比的增大,基础隔震结构的上部结构损伤和隔震层损伤均增大,且上部结构的损伤明显滞后于隔震支座损伤,IV 场地在同等条件下损伤最严重;中长周期地震波对于隔震结构损伤影响较大;选取了层间位移角、隔震层位移作为抗震性态水平的量化指标,基于计算结果,本文初步给出了两类指标与结构?土体相对刚度比的预测公式,提出了不同类别场地下小高宽比基础隔震结构的抗震性态水平划分及其破坏程度的物理描述。 相似文献
350.
Cui Meng Guo Qingjun Wei Yujun Yu Xuening Hu Jian Tian Liyan Kong Jing 《Environmental science and pollution research international》2023,30(2):2450-2468
Environmental Science and Pollution Research - Since the millennium, China has economically taken off with rapid urbanization, and anthropogenic nitrogen emission intensity has undergone remarkable... 相似文献