处理垃圾渗滤液的Fe/C空气阴极MFC性能研究

用浸渍法制得硝酸铁/活性炭粉催化剂,通过吸附法将催化剂吸附到碳毡上制作Fe/C催化剂碳毡空气阴极电极.通过改变初始活性炭粉投加量和硝酸铁浓度,考察了两者对以垃圾渗滤液为燃料的MFC产电性能影响;通过循环伏安测试,对不同硝酸铁浓度下自制阴极电极性能进行了评价;在最佳催化条件下考察了装置运行稳定性;并对不同进水COD浓度下同步产电和污水净化性能进行了研究.结果表明,随着活性炭粉投加量或硝酸铁浓度的增加,MFC产电性能均呈现先升高后降低的趋势;当活性炭粉投加量为1 g且硝酸铁浓度为0.25 mol.L-1时,电池性能最佳,功率密度为4 199.8 mW.m-3,表观内阻为465Ω;在硝酸铁和活性炭粉最佳比范围内,MFC的内阻和功率密度分别随着催化剂量的增加而减小和增加;循环伏安测试进一步表明,硝酸铁浓度为0.25 mol.L-1时放电容量最大,且性能稳定;在最佳催化条件下,随着进水COD浓度的增加,MFC产电性能增加,功率密度达5 478.92 mW.m-3,同时COD去除量也增加,最大为1 505.2 mg.L-1,垃圾渗滤液的COD去除率最大达89.1%.     

几种高硅质矿物细颗粒的A549细胞毒性对比

以大气颗粒物成分中主要矿物相:石英、绢云母、钠长石和蒙脱石这4种高硅质矿物细颗粒为研究对象,检测其对A549细胞存活率、膜损伤及炎性因子释放的影响,旨在对比分析几种高硅质矿物细颗粒的毒性大小,并从颗粒物物理化学性质角度阐述其细胞毒性作用机制.结果表明,几种硅质细颗粒对A549细胞存活率的影响:蒙脱石绢云母≥石英钠长石.细胞存活率与矿物颗粒样品的SiO_2含量之间相关性较差,与Fe_2O_3含量存在较好相关性,Fe_2O_3含量越高毒性越大.高硅质矿物颗粒共培养环境中H_2O_2释放量与样品中Fe_2O_3含量呈正相关关系.蒙脱石组细胞受H_2O_2影响最大,石英和钠长石组细胞受粉体释放H_2O_2影响较小.所检测的几种高硅质矿物颗粒不同程度地造成细胞膜损伤,且均可触发A549细胞释放TNF-α或IL-6,进一步激发免疫反应的产生,但不同类型的高硅质矿物颗粒促发炎性反应不同.高硅质矿物细颗粒的成分结构并不是影响其生物活性的唯一因素,粉体的外在形态、表面活性基团、溶解性、吸附和离子交换特性等对细胞的存活率、细胞膜损伤、液相自由基的释放及炎性反应的影响同样不容忽视.     

太阳能光伏废水处理设施脱氮功能优化实例

某太阳能光伏企业的生产废水约4000 m³/d,废水中的主要污染物是少量的氟离子和大量硝态氮,原废水工艺中缺少去除硝态氮的功能。在原废水处理设施基础上,将生化处理工艺优化为“A/O反硝化”工艺,增加碳源投加设备。工程实践表明,工艺优化后,硝态氮得以有效去除,TN去除率达到95%,出水水质达到《电池工业污染物排放标准》(GB30484—2013)表2的间接标准。     

中国光伏发电的时空分布、竞争格局及减排效益

随着中国碳达峰、碳中和目标的提出,光伏发电逐渐成为推动低碳转型的重要途径。通过开展中国光伏发电的时空分布、竞争格局及减排效益研究,本文力求为中国“双碳”目标的落实、光伏产业的可持续发展提供量化支撑及政策建议,得出主要结论如下：（1）2012—2020年,光伏装机总量从624.8万kW增长到25317.0万kW,以集中式电站为主导;（2）山东、江苏、安徽、河南、山西等地区呈现高—高自相关特征,贵州等地区呈现高—低自相关特征;（3）电力消费量、碳排放量、科研投入为装机量增加的正向驱动因素,科技投入对相邻省份的装机量增加同样具有正向驱动效应;（4）中国现有光伏装机的年均减排效益约为2.0亿t,到2030年累计可以达到19.2亿t,对碳达峰、碳中和目标的落实具有重要推动作用。     

Magnetic-activated cell sorting (MACS) significantly decreases the hybridization efficiency of fluorescence in situ hybridization (FISH)

Fetal cells were enriched from maternal blood using density gradient centrifugation of Histopaque followed by magnetic-activated cell sorting (MACS) to select CD71-positive cells. For each specimen, cells partially purified by Histopaque were split into equal portions, and each portion was subjected to purification by MACS in parallel. Cells before and after MACS were subjected to dual-color fluorescence in situ hybridization (FISH) analysis with X- and Y-chromosome-specific probes. We found that the hybridization rates were decreased by approximately 10% after MACS based on duplicated analysis for each sample. Copyright © 2001 John Wiley & Sons, Ltd.     

Significantly higher number of fetal cells in the maternal circulation of women with pre-eclampsia

Although the pathophysiology of pre-eclampsia is unknown, several studies have indicated that abnormal placentation early in pregnancy might play a key role. It has recently been suggested that this abnormal placentation may result in transfusion of fetal cells (feto-maternal transfusion) in women with pre-eclampsia. In the present study, fetal nucleated red blood cells were isolated from 20 women with pre-eclampsia and 20 controls using a very efficient magnetic activated cell sorting (MACS) protocol. The number of male cells was determined using two-color fluorescence in situ hybridization (FISH) for X and Y chromosomes. Significantly more XY cells could be detected in women with pre-eclampsia (0.61±1.2 XY cells/ml blood) compared to women with uncomplicated pregnancies (0.02±0.04 XY cells/ml blood) (Mann–Whitney U-test, p<0.001). These results suggest that fetal cell trafficking is enhanced in women with pre-eclampsia, and this finding may contribute to the understanding of the pathophysiology of the disease. Copyright © 2001 John Wiley & Sons, Ltd.     

微生物燃料电池用于废水能源化的研究进展

微生物燃料电池能将废水中有机物的化学能转换成电能,在完成污染去除的同时实现能量回收,是一种新型的环境生物电化学技术。文章介绍了微生物燃料电池的工作原理,系统地总结了微生物燃料电池的技术体系构成要素,从电极构造、产电微生物、质子交换膜、反应器设计等方面阐述了微生物燃料电池研究现状与存在问题。针对微生物燃料电池在未来工程应用要求,指出反应器构型设计、生物电化学技术耦合等为未来研究重点。     

运行微生物燃料电池减排稻田土壤甲烷的研究

为了研究稻秆还田条件下运行微生物燃料电池(microbial fuel cells,MFCs)是否能有效减排稻田甲烷,本研究将添加质量分数0.5%稻秆的土壤装入MFCs反应器,淹水并种植水稻后运行MFCs.待水稻经历苗期、分蘗期、晒田期、灌浆期和成熟期共98 d后,停止MFCs运行.在MFCs运行过程中实时连续记录电压,每周一次采用静态箱法搜集并检测反应器的甲烷排放通量.结果表明,MFCs电流在分蘗期逐步升高并达到峰值,并且运行MFCs显著降低添加稻秆土壤在苗期和分蘗期的甲烷累积排放通量.原因可能与产电菌和产甲烷菌竞争有机底物有关.MFCs运行98 d后,水稻株高、地上和地下部分生物量,以及产量未受显著影响.本研究为稻田CH_4减排提供了一种潜在的绿色可持续的技术.     

Cadmium sulfide nanoparticle induces oxidative stress and pro-inflammatory effects in human lung adenocarcinoma epithelial cells

Cadmium sulfide nanoparticles (CdSNP) are increasingly used in biological applications. This study was undertaken to understand the mechanisms underlying adverse effects of CdSNP using human lung adenocarcinoma epithelial (A549) cells. Cellular toxicity was evaluated by using 3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyltetrazolium bromide and neutral red assays. Results showed that CdSNP reduced mitochondrial function and induced lysosomal activity in concentration and time-dependent manner. CdSNP produced oxidative stress as evidenced by reduction of glutathione (GSH) levels and increase in reactive oxygen species and lipid peroxidation levels. Induction of caspase-3 enzymes and condensed, fragmented nuclei was observed in CdSNP-treated cells. Furthermore, the levels of interleukin-8, tumor growth factor and DNA fragmentation were significantly higher in CdSNP exposed cells. Data indicated that toxicity of CdSNP noted in A549 cells may be mediated through oxidative stress. This study warrants more comprehensive assessment of CdSNP prior to industrial applications.