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1.
Xu  Peiwei  He  Xiaoqing  He  Shengliang  Luo  Jinbin  Chen  Qiang  Wang  Zuoyi  Wang  Aihong  Lu  Beibei  Wu  Lizhi  Chen  Yuan  Xu  Dandan  Chen  Weizhong  Chen  Zhijian  Wang  Xiaofeng  Lou  Xiaoming 《Environmental science and pollution research international》2021,28(6):6691-6699
Environmental Science and Pollution Research - To better understand the cardiopulmonary alterations associated with personal exposed PM2.5-bound heavy meals, we conducted a cross-sectional study in...  相似文献   
2.
Huang  Ying  Jiang  Qiongji  Yu  Xubiao  Gan  Huihui  Zhu  Xia  Fan  Siyi  Su  Yan  Xu  Zhirui  He  Cunrui 《Environmental science and pollution research international》2021,28(37):51251-51264
Environmental Science and Pollution Research - Trace copper ion (Cu(II)) in water and wastewater can trigger peroxymonosulfate (PMS) activation to oxidize organic compounds, but it only works under...  相似文献   
3.
• The long-period groundwater evolution was identified by hydrochemical signatures. • The dominant processes in the groundwater evolution were verified. • Groundwater quality in the coastal areas was susceptible to deterioration due to SI. • Groundwater contamination arose from fertilizer, livestock manure & domestic sewage. The evolution of hydrochemical compositions influenced by long-period interactions between groundwater and the geo-environment is a fundamental issue for exploring groundwater quality and vulnerability. This study systematically investigated the hydrochemical processes and anthropogenic interference occurring in the river basin by bivariate plots, Gibbs diagrams, saturation index, and the major ions ratios. Apparent changes in groundwater hydrochemistry have been observed in the study area, illustrating the origins of major ions are affected by various internal and external factors. Results highlighted that TDS varied from freshwater to brackish water, ranging between 187.90 and 2294.81 mg/L. Ca2+ and HCO3 are the dominant ions in the studied samples. The results gained by Gibbs diagrams, bivariate plots, saturation index, and the major ions ratios demonstrated that minerals dissolution/precipitation, cation exchange, and human inputs play crucial roles in the unconfined aquifers. Moreover, the overuse of nitrogen fertilizer, livestock manure, and industrial/domestic sewage led to nitrate and nitrite contamination and brought significant challenges to the surrounding hydrogeo-environment. The present study could make an unambiguous identification of natural processes and anthropogenic interventions influencing groundwater hydrochemistry’s long-period evolution and create a preliminary strategy for groundwater resources management.  相似文献   
4.
• Pore structure affects biologically activated carbon performance. • Pore structure determines organic matter (OM) removal mechanism. • Microbial community structure is related to pore structure and OM removal. Optimizing the characteristics of granular activated carbon (GAC) can improve the performance of biologically activated carbon (BAC) filters, and iodine value has always been the principal index for GAC selection. However, in this study, among three types of GAC treating the same humic acid-contaminated water, one had an iodine value 35% lower than the other two, but the dissolved organic carbon removal efficiency of its BAC was less than 5% away from the others. Iodine value was found to influence the removal of different organic fractions instead of the total removal efficiency. Based on the removal and biological characteristics, two possible mechanisms of organic matter removal during steady-state were suggested. For GAC with poor micropore volume and iodine value, high molecular weight substances (3500–9000 Da) were removed mainly through degradation by microorganisms, and the biodegraded organics (soluble microbial by-products,<3500 Da) were released because of the low adsorption capacity of activated carbon. For GAC with higher micropore volume and iodine value, organics with low molecular weight (<3500 Da) were more easily removed, first being adsorbed by micropores and then biodegraded by the biofilm. The biomass was determined by the pore volume with pore diameters greater than 100 μm, but did not correspond to the removal efficiency. Nevertheless, the microbial community structure was coordinate with both the pore structure and the organic removal characteristics. The findings provide a theoretical basis for selecting GAC for the BAC process based on its pore structure.  相似文献   
5.
Environmental Chemistry Letters - Wastewater from the uranium mining industry contains toxic arsenate (AsO43–), selenate (SeO42–), and molybdate (MoO42–) that can be removed by...  相似文献   
6.
赵旭  冒冉  李昂臻  孙拓  乔梦 《环境工程学报》2020,14(7):1728-1734
电解法是利用电能实现氧化还原反应的方法,其应用于消毒通常有电产次氯酸钠消毒剂和电化学消毒2种方式。为深入了解电产次氯酸钠及电化学消毒技术机理,进一步探讨电解法在水处理和公共环境卫生消毒领域的应用,从消毒原理、技术特点、使用方法和消毒应用方面,对电解法制备次氯酸钠与电化学消毒水处理技术进行了介绍与分析,并提出了目前存在的问题和技术发展前景,为该技术的实际应用提供参考。  相似文献   
7.
为解决现行安全生产科技领域中全球定位系统(GPS)/惯性导航系统(INS)融合系统容易产生较大时变误差的关键问题,满足GPS定位信号的精度和信号数据处理时间的要求,提出1种群调度滤波算法,通过实验仿真,分别与模糊算法、机器学习算法及卡尔曼滤波网络算法进行比较研究。结果表明:群调度滤波算法兼顾了定位精度与数据处理时间,具有较大优势,可在航空安全、船舶安全、应急监测、灾后抢险等安全科技领域广泛应用。  相似文献   
8.
Yan  Mi  He  Lei  Prabowo  Bayu  Fang  Zhumin  Lin  Jie  Xu  Zhang  Hu  Yanjun 《Journal of Material Cycles and Waste Management》2018,20(3):1594-1604
Journal of Material Cycles and Waste Management - Efforts to improve the performance of hydrothermal treatment (HT) in producing high-quality solid fuel from sewage sludge were carried out by...  相似文献   
9.
从珠江口海域分离、鉴定出3种重要有害藻类小普林藻JX12(Prymnesium parvum)、剧毒卡尔藻JX24(Karlodinium veneficum)、红色赤潮藻JX14(Akashiwo sanguinea),在实验室条件下研究了不同反应温度和pH值对小普林藻溶血活性的影响,在此基础上对海洋微藻溶血活性的测定方法进行了优化,并进一步分析比较了不同藻株以及不同生长时期溶血毒性的变化特征。研究结果显示,在实验温度范围内(4~50°C),小普林藻的溶血活性随温度的升高而增大,37℃为其最佳反应温度,pH 8和50 min为其最佳反应条件。不同生长时期的小普林藻溶血毒性具有显著差异,对数期溶血活性(5.67×10~(-7)HU·cell~(-1))显著高于稳定期(2.32×10~(-7)HU·cell~(-1))和衰亡期(3.40×10~(-7)HU·cell~(-1))。分离自珠江口海域的3种微藻均检测出溶血毒性,单个细胞溶血活性由强到弱分别为红色赤潮藻(976.20×10~(-7)HU·cell~(-1))、小普林藻(5.67×10~(-7)HU·cell~(-1))、剧毒卡尔藻(2.58×10~(-7)HU·cell~(-1))。值得注意的是,红色赤潮藻中国株JX14的单位细胞溶血活性显著高于美国株AS2,是后者的2倍以上。本研究首次确认珠江口海域红色赤潮藻、小普林藻和剧毒卡尔藻均具有较强的溶血毒性,这些有害藻类一旦形成赤潮可能对河口生态系统安全以及水产养殖业造成严重危害。  相似文献   
10.
采用溶胶-凝胶法制备了Mn掺杂钙钛矿型催化剂LaFexMn1-xO3,并以其为催化剂催化湿式双氧水氧化处理煤气化废水纳滤浓缩液。采用XRD,SEM,FTIR技术对催化剂进行了表征。表征结果显示:制备的催化剂均具有标准的钙钛矿型结构,其中,LaFe0.9Mn0.1O3的结构稳定,比表面积大。实验结果表明:制备的催化剂中LaFe0.9Mn0.1O3的催化活性最高,且稳定性好,连续使用5次后催化活性未见明显减弱;在H2O2投加量3.0 g/L、n(H2O2)∶n(LaFe0.9Mn0.1O3)=12∶1、反应温度160 ℃、反应压力1 MPa、浓缩液pH 3、反应时间60 min的最优条件下,COD、UV254和TOC的去除率分别达到80.9%、95.2%和68.0%,BOD5/COD由0.02提升至0.40,可生化性大幅提高。  相似文献   
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