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细河流域地下水中持久性有机氯污染物的健康风险评价 被引量:7
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作者 罗庆 孙丽娜 张耀华 《水土保持研究》 CSCD 北大核心 2011年第6期119-124,共6页
为了保障细河流域沿岸居民的生活用水安全,分析了地下水样品中15种持久性有机氯污染物(POCPs)的含量,运用荷兰公共卫生和环境国家研究院提出的土壤地下水污染现场暴露评价(CSOIL)模型对持久性有机氯污染物的健康风险进行了初步评价。结... 为了保障细河流域沿岸居民的生活用水安全,分析了地下水样品中15种持久性有机氯污染物(POCPs)的含量,运用荷兰公共卫生和环境国家研究院提出的土壤地下水污染现场暴露评价(CSOIL)模型对持久性有机氯污染物的健康风险进行了初步评价。结果表明:细河流域各采样点地下水中∑PCBs含量为0.08~5.89ng/L,∑OCPs含量为0.17~21.2ng/L,均低于各自生活饮用水卫生标准(GB5749-2006)中的浓度限值。作物食入、饮水等经口摄入途径是地下水环境健康风险评价中最主要的暴露途径,各采样点地下水中POCPs由作物食入、饮水、洗澡过程中呼吸吸入和皮肤接触4种暴露途径产生的总的平均个人年健康风险值为1.63×10-7~6.21×10-6 a-1,其健康风险排序为:翟家>富官>双树>前庙>土西>大兀拉>黄蜡坨>前余>大潘,均低于国际辐射防护委员会(ICRP)推荐的最大可接受值,基本属于可接受范围,但其健康危害已不容忽视。 展开更多
关键词 细河流域 地下水 持久性有机氯污染物 CSOIL模型 健康风险评价
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区域环境污染负荷分析的干预——效应法
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作者 高长波 陈新庚 +1 位作者 莫创荣 孙艳军 《环境监测管理与技术》 北大核心 2006年第1期44-47,共4页
介绍了基于生命周期影响评价模型的干预———效应法,以及该法包括的环境效应类型的确定、环境干预因子的识别与归类、按当量因子法汇总、数据标准化和赋权评估5个技术步骤,并以广州市2003年监测数据为基础,对广州市酸化、富营养化和光... 介绍了基于生命周期影响评价模型的干预———效应法,以及该法包括的环境效应类型的确定、环境干预因子的识别与归类、按当量因子法汇总、数据标准化和赋权评估5个技术步骤,并以广州市2003年监测数据为基础,对广州市酸化、富营养化和光化学臭氧合成效应作了研究。结果表明,广州市2003年排放的酸化污染负荷量约为379.5×103t SO2当量,主要污染物是SO2的排放(占57.4%);富营养化污染负荷量为657.7×103tNO3-当量,其中最大排放源来自人类生活(占38.4%);光化学臭氧合成污染负荷量为46.4×103t C2H4当量,主要来自于公路交通运输(占69.8%)。赋权评估表明广州市区域性的环境效应主要为光化学臭氧合成,其环境负荷为32.358×103人当量,其次为富营养化和酸化效应,环境负荷分别为8.138×103人当量和7.915×103人当量。 展开更多
关键词 环境污染负荷 干预——效应法 酸化 富营养化 光化学臭氧合成
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基于聚类方法的民声通道共性问题研究分析
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作者 梁丹凝 梁坚 《江西科学》 2013年第3期396-398,共3页
通过SPSS Clementine智能分析工具中的K-Means方法对民声通道系统原始数据进行聚类研究,发现其中存在的共性问题并进行分析,挖掘群众关注较高的突出问题,为决策者提供有价值的管理策略。
关键词 数据挖掘 聚类分析 K-MEANS 民声通道
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民声通道数据仓库的设计与实现
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作者 梁丹凝 龙草芳 《电脑知识与技术》 2013年第6期3663-3665,共3页
该文给出了民声通道数据仓库的设计与实现方案,对不同数据源和不同格式的数据进行抽取、清洗、集成、转换和加载,最后建立了民声通道数据仓库,并且对民声通道数据仓库进行OLAP分析,将数据信息结构详细分析并可视化呈现。
关键词 数据仓库 OLAP分析 民声通道
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Trends of chemical speciation profiles of anthropogenic volatile organic compounds emissions in China, 2005-2020 被引量:16
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作者 Wei WEI Shuxiao WANG +1 位作者 Jiming HAO Shuiyuan CHENG 《Frontiers of Environmental Science & Engineering》 SCIE EI CAS CSCD 2014年第1期27-41,共15页
This study estimates the detailed chemical profiles of China's anthropogenic volatile organic com- pounds (VOCs) emissions for the period of 2005-2020. The chemical profiles of VOCs for seven activity sectors are c... This study estimates the detailed chemical profiles of China's anthropogenic volatile organic com- pounds (VOCs) emissions for the period of 2005-2020. The chemical profiles of VOCs for seven activity sectors are calculated, based on which the Photochemical Ozone Creation Potential (POCP) of VOCs for these sectors is evaluated. At the national level, the VOCs species emitted in 2005 include alkanes, alkenes and alkynes, aromatic compounds, alcohols, ketones, aldehydes, esters, ethers and halocarbons, accounting for 26.4wt.%, 29.2wt.%, 21.3 wt.%, 4.7 wt.%, 5.4 wt.%, 1.7 wt.%, 2.1 wt.%, 0.7 wt. % and 2.2wt.% of total emissions, respectively. And during 2005-2020, their mass proportions would respec- tively grow or decrease by - 34.7%, -48.6%, 108.5%, 6.9%, -32.7%, 7.3%, 65.3%, 100.5%, and 55.4%. This change would bring about a 13% reduction of POCP for national VOCs emissions in the future. Thus, although the national VOCs emissions are expected to increase by 33% over the whole period, its ozone formation potential is estimated to rise only by 14%. Large discrepancies are found in VOCs speciation emissions among provinces. Compared to western provinces, the eastern provinces with a more developed economy would emit unsaturated hydrocarbons and benzene with lower mix ratios, and aromatic compounds except benzene, oxidized hydrocar- bons and halocarbons with higher mix ratios. Such differences lead to lower POCP of VOCs emitted in eastern provinces, and higher POCP of VOCs emitted in western provinces. However, due to the large VOCs emissions from Chinese eastern region, the ozone forma- tion potential of VOCs emission in eastern provinces would be much higher than those in western provinces by about 156%-235%. 展开更多
关键词 volatile organic compounds (VOCs) chemi-cal speciation ozone formation Photochemical OzoneCreation Potential pocp China
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High quality genome sequences of thirteen Hypoxylaceae(Ascomycota)strengthen the phylogenetic family backbone and enable the discovery of new taxa 被引量:1
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作者 Daniel Wibberg Marc Stadler +6 位作者 Christopher Lambert Boyke Bunk Cathrin Spröer Christian Rückert Jörn Kalinowski Russell JCox Eric Kuhnert 《Fungal Diversity》 SCIE 2021年第1期7-28,共22页
The Hypoxylaceae(Xylariales,Ascomycota)is a diverse family of mainly saprotrophic fungi,which commonly occur in angiosperm-dominated forests around the world.Despite their importance in forest and plant ecology as wel... The Hypoxylaceae(Xylariales,Ascomycota)is a diverse family of mainly saprotrophic fungi,which commonly occur in angiosperm-dominated forests around the world.Despite their importance in forest and plant ecology as well as a prolific source of secondary metabolites and enzymes,genome sequences of related taxa are scarce and usually derived from envi-ronmental isolates.To address this lack of knowledge thirteen taxonomically well-defined representatives of the family and one member of the closely related Xylariaceae were genome sequenced using combinations of Illumina and Oxford nanopore technologies or PacBio sequencing.The workflow leads to high quality draft genome sequences with an average N50 of 3.0 Mbp.A backbone phylogenomic tree was calculated based on the amino acid sequences of 4912 core genes reflecting the current accepted taxonomic concept of the Hypoxylaceae.A Percentage of Conserved Proteins(POCP)analysis revealed that 70%of the proteins are conserved within the family,a value with potential application for the definition of family boundaries within the order Xylariales.Also,Hypomontagnella spongiphila is proposed as a new marine derived lineage of Hypom.monticulosa based on in-depth genomic comparison and morphological differences of the cultures.The results showed that both species share 95%of their genes corresponding to more than 700 strain-specific proteins.This difference is not reflected by standard taxonomic assessments(morphology of sexual and asexual morph,chemotaxonomy,phylogeny),preventing species delimitation based on traditional concepts.Genetic changes are likely to be the result of environmental adaptations and selective pressure,the driving force of speciation.These data provide an important starting point for the establishment of a stable phylogeny of the Xylariales;they enable studies on evolution,ecological behavior and biosynthesis of natural products;and they significantly advance the taxonomy of fungi. 展开更多
关键词 AAI ANI Cazyme Oxford nanopore PHYLOGENOMICS pocp XYLARIALES
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