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561.
颗粒物中重金属元素可对人体健康造成不利影响,粒径越小危害越大.利用在线重金属观测仪于2021年1月7~25日在郑州市连续测定PM1中Al、 Si、 K、 Ca、 V、 Cr、 Mn、 Fe、 Ni、 Cu、 Zn、 As、 Se、 Ba、 Pb和Cd共16种重金属元素.结果表明,观测期间ρ(K)的浓度最高(0.62μg·m-3).根据污染物浓度和气象特征,将观测期间划分为清洁日、沙尘日和霾日.大气PM1中重金属污染特征和健康风险评价在不同污染过程下的贡献不同.利用美国EPA健康风险评价法评估重金属的健康风险,采用富集因子法和正定矩阵因子模型(PMF)解析重金属来源,并利用浓度权重轨迹分析法(CWT)和后向轨迹法对传输的影响进行评估.结果表明在不同污染过程下Zn、 As、 Se、 Pb和Cd的富集因子超过100,均受人类活动影响较大.在观测期间重金属主要来源为工业源、燃煤/生物质源、机动车源和扬尘源.将健康风险结果代入PMF分析发现,在清洁日、沙尘日和霾日期间工业源是致癌与非致癌健康风险的主要贡献源,且本地区PM...  相似文献   
562.
Journal of Material Cycles and Waste Management - Red gypsum comes from TiO2 production industry by sulfate method, which comes from the low acidic liquid stream treatment using lime or limestone....  相似文献   
563.
564.

In this paper, Web of Science (a database) is used to retrieve related literature in the field of heavy metal pollution in desert. CiteSpace is used to make a quantitative and qualitative evaluation on the literature in the field on the basis of a brief analysis on the research status, research focus, and evolution process in the field. Through CiteSpace visual analysis, a comparative analysis is given on related literature in terms of annual number of published papers, author groups, and their countries and regions, journals, publishing institutions, highly cited papers, research focuses, and burst terms, so as to explore the research status and future development trend of the field on a global scale. The results are shown as follows: (1) The literature in the field was originally published in 2000; the number of published papers increased steadily. The literature was mostly published on high-quality journals, the USA topped in terms of the number of published papers, and the research results achieved by developed countries had a greater influence. Chinese Acad Sci topped with the highest centrality and most published papers, which have made outstanding contributions to the field and occupy a leading position in the field. However, the fact is that there lacks communication and cooperation among research institutions. The most influential journal is Science of the Total Environment. (2) The hot research words in the field are as follows: heavy metal, soil, pollution, lead, desert, cadmium, and microelement. (3) In the field, burst terms have transformed from atmospheric deposition, biomonitoring, and phytoremediation to trace element, stream sediment, street dust, and water quality, and finally transformed to river and sediment. New words keep emerging in the research, and more and more attention is paid to the issue of heavy metal pollution in river sediment, which will be a future research hotspot in the field.

  相似文献   
565.
Environmental Science and Pollution Research - The European Union (EU) Emissions Trading System is the most important means for the EU to achieve carbon neutrality, but it has been severely...  相似文献   
566.

The generation estimation of retired mobile phones is launched with the sales and new method using the revised sales data and amount of the subscribers. Several assumptions have been made due to the insufficient sources of the data. The sales data of legal mobile phones are calculated with the authoritative and continuous official data. The sales data of smuggled and counterfeit mobile phones in China are also estimated based on the behavior data collected from the questionnaires. The results of generation estimation show that there are 636.52 million mobile phones retired in 2020, compared with 14.44 million in 1999 and several negative values in 2000, 2001, and 2008. The annual total mass of retired mobile phones in China escalated with the contributions of both the increasing generation amount and constant mass of the single unit. There are 50,921.60 ton of mobile phones retired in 2020 compared with 1155.20 ton in 1999, while the peak is 58,131.20 ton in 2019. There are 26,066.80 ton of retired mobile phones are stockpiled in 2020, while 16,152.40 ton and 8702.40 ton of retired mobile phones are reused as a whole unit and recycled, respectively. In the retired mobile phones that are recycled, 4600.50 ton material is recovered and 1216.50 ton components are reused, while 2885.40 ton residues need final disposal. The amount and dynamic characteristics of metals in the retired mobile phones are also calculated. Based on the results, several policy implications are made to improve sustainable management system of retired mobile phones in China.

  相似文献   
567.
Environmental Science and Pollution Research - Strategic valorization of readily available sugarcane bagasse (SB) is very important for waste management and sustainable biorefinery. Conventional SB...  相似文献   
568.
Environmental Science and Pollution Research - Nitrogen fertilizer has considerable effects on soil carbon fluxes. However, the responses of soil CO2 emission to N fertilizer remain controversial....  相似文献   
569.
沙漠化灾害危险度评价的初步研究   总被引:10,自引:0,他引:10  
沙漠化是全球重大灾害之一,本文从我国实际出发,根据沙漠化灾害危险度评价研究的基本内容,提出了沙漠化灾害危险度评价因子系统并作出了四级量化划分,首次提出了沙漠化灾害危险度定量评价的标准与方法,并进行了实例应用和验证.  相似文献   
570.
武汉月湖水体营养物质的分布与硅藻的生态指示   总被引:5,自引:0,他引:5  
通过对武汉月湖2007年1-12月水体理化指标(电导率、溶解氧、pH值、水温、透明度、无机氮、无机磷、可溶硅)、生物指标(硅藻、蓝藻、叶绿素a)的监测,结果表明:月湖水体中无机氮、无机磷含量较丰富,可溶硅含量较低;月湖水体初级生产力较高,湖泊中蓝藻密度远大于硅藻密度;月湖水体中浮游植物与生境因素有着复杂的生态网络关系.月湖水体营养盐结构不合理,在硅藻消亡后,湖泊水域中的营养组合(丰富的氮与磷,但缺乏可溶硅),这种特殊生境刺激蓝藻的生长,进一步导致硅藻的减少,使月湖浮游植物的优势种转变成蓝藻类.可溶硅在湖泊浮游植物群落由硅藻型向蓝藻演变的过程中起着重要的作用,可溶硅起始浓度水平不仅决定硅藻生产量最大值的程度,而且制约着硅藻持续时间,补偿湖泊可溶硅可能是防治湖泊富营养化的新路.  相似文献   
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