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971.
A scaled up microbial fuel cell (MFC) of a 50 L volume was set up with an oxic-anoxic two-stage biocathode and activated semicoke packed electrodes to achieve simultaneous power generation and nitrogen and organic matter removals. An average maximum power density of 43.1 W·m^-3 was obtained in batch operating mode. By adjusting the two extemal resistances, the denitrification in the A-MFC and power production in the O-MFC could be enhanced. In continuous mode, when the hydraulic retention times were set at 6 h, 8 h and 12 h, the removal efficiencies of COD, NHf-N and total nitrogen (TN) were higher than 95%, 97%, and 84%, respectively. Meanwhile the removal loads for COD, NH4^+-N and TN were10, 0.37 and 0.4 kg·(m^3·d)^-1, respectively.  相似文献   
972.
毛兰素对人肝癌Huh7细胞的抑制作用   总被引:2,自引:0,他引:2  
研究了从鼓槌石斛中分离得到的低分子量天然化合物毛兰素在体外对人肝癌Huh7细胞的增殖抑制作用,并探讨其诱导细胞凋亡的分子机制.实验结果显示:毛兰素能显著抑制肝癌Huh7细胞的增殖,且随着药物浓度与时间增加其抑制率呈明显的剂量时间效应,其48 h半数抑制浓度IC50为37.4 nmol/L;毛兰素能诱导人肝癌Huh7细胞凋亡并使其细胞周期阻滞于G2-M期;分子机制研究显示毛兰素可抑制Akt激酶活性、下调Mcl-1蛋白表达以及激活PARP活性从而导致其对Huh7癌细胞的增殖抑制作用.以上结果初步表明毛兰素对肝癌防治具有潜在药用价值.图5参17  相似文献   
973.
利用厌氧污泥为接种源构建双室微生物燃料电池(Microbial fuel cell,MFC),研究其电子传递机制,并考察其底物利用谱及阴极电子受体对产电性能的影响.结果表明:该MFC主要通过生物膜机制实现电子从有机物到固体电极的传递过程.该混合菌MFC的底物利用谱范围广泛,单糖、二糖、小分子有机酸等有机物均可作为电子供体产电,其中以蔗糖和乳糖为底物产电效果较好,最大功率密度分别为69.69 mW/m2和60.75 mW/m2;而以乙醇为底物时,COD负荷最高,达123.55 mg L-1d-1.阴极不同电子受体对混合菌群MFC的产电性能也有显著影响,其中以KMnO4为电子受体电池性能最好,最大功率密度达1 396.74 mW/m2.  相似文献   
974.
● A novel hybrid fuel cell (F-HFC) was fabricated. ● Pollutant degradation and synchronous electricity generation occurred in F-HFC. ● BiOCl-NH4PTA photocatalyst greatly improved electron transfer and charge separation. ● Pollutant could act as substrate directly in ambient conditions without pretreatment. ● The mechanism of the F-HFC was proposed and elucidated. The development of highly efficient energy conversion technologies to extract energy from wastewater is urgently needed, especially in facing of increasing energy and environment burdens. Here, we successfully fabricated a novel hybrid fuel cell with BiOCl-NH4PTA as photocatalyst. The polyoxometalate (NH4PTA) act as the acceptor of photoelectrons and could retard the recombination of photogenerated electrons and holes, which lead to superior photocatalytic degradation. By utilizing BiOCl-NH4PTA as photocatalysts and Pt/C air-cathode, we successfully constructed an electron and mass transfer enhanced photocatalytic hybrid fuel cell with flow-through field (F-HFC). In this novel fuel cell, dyes and biomass could be directly degraded and stable power output could be obtained. About 87 % of dyes could be degraded in 30 min irradiation and nearly 100 % removed within 90 min. The current density could reach up to ~267.1 μA/cm2; with maximum power density (Pmax) of ~16.2 μW/cm2 with Rhodamine B as organic pollutant in F-HFC. The power densities were 9.0 μW/cm2, 12.2 μW/cm2, and 13.9 μW/cm2 when using methyl orange (MO), glucose and starch as substrates, respectively. This hybrid fuel cell with BiOCl-NH4PTA composite fulfills the purpose of decontamination of aqueous organic pollutants and synchronous electricity generation. Moreover, the novel design cell with separated photodegradation unit and the electricity generation unit could bring potential practical application in water purification and energy recovery from wastewater.  相似文献   
975.
建立了加速溶剂提取-凝胶渗透色谱净化和气相色谱-质谱联用快速分析土壤中16种多环芳烃的新方法。方法的检出限、定量限分别为1.1~12μg/kg、3.7~40μg/kg。16种PAHs的回收率为76.6%~96.8%,相对标准偏差为2.9%~9.5%。应用于多个环境样品的分析测试,结果满意。  相似文献   
976.
填料型微生物燃料电池产电特性的研究   总被引:6,自引:0,他引:6  
将石墨和碳毡作为阳极填料组装成填料型微生物燃料电池,其启动期在1 d左右,低于平板型微生物燃料电池的启动期.碳毡作为填料时,微生物燃料电池的最大产电功率密度为1 502 mW/m2(37.6 W/m3),优于石墨作为填料的MFC.将碳毡与碳纸烧结一体以提高填料型微生物燃料电池阳极的导电性,与平板型微生物燃料电池相比,其面积内阻从0.071 Ω穖2下降到0.051 Ω穖2,最大电流密度从3 000 mA上升到8 000 mA,最大产电功率密度从1 100 mW/m2(27.5 W/m3)上升到2426 mW/m2(60.7W/m3),阳极电势平均下降100 mV.循环流量影响填料型微生物燃料电池的产电能力,当流量低于1 mL/min时,其产电功率密度随流速降低而下降.填料型微生物燃料电池在外电阻为600 Ω下长期稳定运行30 d以上,其库仑效率约为10.6%.  相似文献   
977.
采用美国NIOSH method 2010方法用气相色谱仪对合成革废气中的二甲胺浓度进行测定,对仪器条件进行优化,方法的栓出限为0.5mg/m3,相对标准偏差1.23%,回收率为85.0%-94.6%.同时在采样方法上对高浓度二甲胺废气的硅胶穿透问题进行研究,提出用含硫酸0.1mol/L的水溶液做吸收液对二甲胺废气进行吸收采样,在一定程度上解决了高浓度废气样品的穿透问题.  相似文献   
978.
In the typical air polluted city of Shijiazhuang,single inhalable particle samples in non-heating period,heating pened,dust storm days,and snowy days were collected and detected by SEM/EDS(scanning electron microscopy and energy dispersive X-ray spectrometry).The particle morphology was characterized by the 6 shape clusters,which areirregular square,agglomerate,sphere,floccule,column or stick,and unknown,by quantitative order.The irregular square particles are common in all kinds of samples;sphere particles are more,and column or stick are less in winter samples;in the wet deposit samples,agglomerate and floccule particles are not found.The surface of most particles is coarse with fractal edge,which can provide suitable chemical reaction bed in the polluted atmospheric environment.New formed calcium crystal is found to demonstrate the existence of neutralized reaction,explaining the reason for the high SO2 emission and low acid rain frequency in Shijiazhuang.The three sorts of surface patterns of spheres are smooth,semi-smooth,and coarse,corresponding to the element of Si-dominant,Si-Al-dominant,and Fe-dominant.The soot particle is present as floccule with average size around 10 μm,considerably larger than the former reported results,but wrapped or captured with other fine particles to make its appearance unique and enhance its toxicity potentially.The new formed calcium crystal,the 3 sorts of sphere surface patterns,and the unique soot appearance represent the single inhalable particle's morphology characteristics in Shijiazhuang City.  相似文献   
979.
In the present study, bioelectricity generation using a living plant in soil was achieved by converting solar energy into electricity on the principles of plant photosynthesis. The plants Chlorophytum comosum, Chasmanthe floribunda and Papyrus diffuses were used in microbial fuel cells (MFCs) and produced, respectively, a maximum current of 25, 31 and 19 mA/m2, without the use of any nutrient or membrane. In this study, the importance of light was demonstrated by the high current values generated during daytime, and the microorganisms at the anode-rhizosphere interface were examined.  相似文献   
980.
Domestic wastewater contains a considerable amount of pathogenic organisms besides non-biodegradable organics. The conventional technologies followed for the treatment of domestic wastewater are less efficient in removing pathogenic organisms despite substantial removal of dissolved organics. The focal theme of the present investigation was to use a chemo-autotrophic activated carbon oxidation (CAACO) system, an immobilized cell reactor using chemoautotrophs (Bacillus sp.) for the treatment of domestic wastewater. The oxidation of organics and Escherichia coli in wastewater is controlled by the parameters space time, O(2)/COD, bed height and cod loading. The scheme comprised of anaerobic treatment, sand filtration and CAACO treatment removed BOD. COD, Total organic carbon (TOC), dissolved protein, total Kjeldhal nitrogen (TKN) and bacterial count (most probable number (MPN)) by 81%, 92%, 84%, 94%, 93% and 99.9997%, respectively. The low concentration of E. coli in the CAACO-treated wastewater was completely eliminated through UV irradiation in 3 min at 254 nm.  相似文献   
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