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561.
基于电迁移率颗粒物粒径数分布仪(SMPS)、气相色谱-质谱联用(GC-MS)、X-荧光(XRF)方法,于2022—2023年在南京市开展了部分大气新污染物的在线监测,并利用美国国家环境保护局(US EPA)健康风险评价模型评估其健康风险,进一步结合正定矩阵因子分解(PMF)模型对污染物及其健康风险进行来源解析。结果表明,南京市大气中新污染物浓度与其他地区报道的可比,且在遭遇污染过程时显著升高,锰元素的升幅最大(116.3%)。各类新污染物的健康风险均在安全阈值之内。PMF共分解出大气新污染物的5类来源,其中,超细颗粒物(UFPs)主要来自交通源(49%)、光化学(23%)和工业源(28%);重金属主要来自工业源(74%),而挥发性有机物(VOCs)则由工业源(52%)、交通源(25%)和燃烧源(13%)贡献。南京市大气新污染物的非致癌风险由工业源主导,而致癌风险则分别来自交通源、轮船源和工业源。  相似文献   
562.
引入模糊数学中隶属度、权重及模糊矩阵的概念,综合考虑各污染因子状况以确定外排废水的水质情况,更加合理地刻划其外排废水的污染程度,从中找出治理重点,有针对性地加强治理,改善环境。  相似文献   
563.
The connectivity of remnant patches of habitat may affect the persistence of species in fragmented landscapes. We evaluated the effects of the structural connectivity of forest patches (i.e., distance between patches) and matrix class (land-cover type) on the functional connectivity of 3 bird species (the White-crested Elaenia [Elaenia albiceps], the Green-backed Firecrown Hummingbird [Sephanoides sephaniodes], and the Austral Thrush [Turdus falklandii]). We measured functional connectivity as the rate at which each species crossed from one patch to another. We also evaluated whether greater functional connectivity translated into greater ecological connectivity (dispersal of fruit and pollen) by comparing among forest patches fruit set of a plant pollinated by hummingbirds and abundance of seedlings and adults of 2 plants with bird- and wind-dispersed seeds. Interpatch distance was strongly associated with functional connectivity, but its effect was not independent of matrix class. For one of the bird-dispersed plants, greater functional connectivity for White-crested Elaenias and Austral Thrushes (both frugivores) was associated with higher densities of this plant. The lack of a similar association for the wind-dispersed species suggests this effect is linked to the dispersal vector. The abundance of the hummingbird-pollinated species was not related to the presence of hummingbirds. Interpatch distance and matrix class affect animal movement in fragmented landscapes and may have a cascading effect on the distribution of some animal-dispersed species. On the basis of our results, we believe effort should be invested in optimizing patch configuration and modifying the matrix so as to mitigate the effects of patch isolation in fragmented landscapes.  相似文献   
564.
餐饮废水MBR处理过程中DOM的三维荧光光谱分析   总被引:4,自引:1,他引:3       下载免费PDF全文
采用三维荧光(EEM)光谱技术,对膜-生物反应器(MBR)处理餐饮废水过程中的各种溶解性有机物(DOM)进行分析,并对比研究不同水质和容积负荷下DOM的EEM光谱的迁移变化特性和DOM中荧光物质对膜污染速率的影响.结果表明,各种DOM的荧光物质中,蛋白质类物质所占的比重最大,且溶解性微生物代谢产物(SMP)和附着型胞外聚合物(EPS)中的蛋白质类荧光物质对膜污染速率的影响最大,而紧密附着胞外聚合物(TB-EPS)中蛋白质类荧光物质强度与膜污染速率呈强烈的负相关性.腐殖酸溯源表明DOM中的腐殖酸以微生物代谢产生的带有荧光基团的腐殖酸类为主.  相似文献   
565.
通过对比分析美国、欧盟及中国的消费品质量安全风险监管和评估现状,得出我国在消费品法律及标准、伤害监测与事故信息平台及公开、消费品风险辨识及评价程序等方面有待深化研究;基于2012年欧美等国家、地区对我国出口消费品的通报数据的统计分析,识别了主要消费品的隐患及危害类型,给出了伤害情景与三维矩阵集成的消费品风险评价方法,为消费品安全评价提供了新方法、新途径,并以婴儿车为例,进行了应用分析,检验了该方法的可行性。  相似文献   
566.
Accidents and injuries related to work are major occupational health problems in most of the industrialized countries.Traditional approaches to manage workplace safety in mines have mainly focused on job redesign and technical aspects of engineering systems.It is being realized that compliance to rules and regulations of mines is a prerequisite;however,it is not sufficient to achieve further reduction in accident and injury rates in mines.Proactive approaches are necessary to further improve the safety standards in mines.Unsafe conditions and practices in mines lead to a number of accidents,which in turn may cause loss and injury to human lives,damages to property,and loss of production.Hazard identification and risk assessment is an important task for the mining industry which needs to consider all the risk factors at workplaces.Applications of risk management approaches in mines are necessary to identify and quantify potential hazards and to suggest effective solutions.In this paper,the following risk estimation techniques were discussed:(i)DGMS(Directorate General of Mines Safety,India)risk rating criterion,and(ii)a matrix based approach.The proposed tools were demonstrated through an application in an opencast coal mine in India.It was inferred that the risk assessment approach can be used as an effective tool to indentify and control hazards in mines.  相似文献   
567.
盐度冲击下MBR污泥SMP和EPS的三维荧光光谱解析   总被引:1,自引:0,他引:1       下载免费PDF全文
利用三维荧光(EEM)技术研究了不同盐度冲击下膜-生物反应器(MBR)污泥微生物溶解性产物(SMP)和胞外聚合物(EPS)的变化规律,分析不同盐度冲击下MBR污泥SMP和EPS的EEM图谱.结果表明,当冲击盐度大于2.5g/L时,SMP的EEM图谱中色氨酸荧光峰B(270nm,350nm)、类胡敏酸荧光峰C(375,475nm)、类富里酸荧光峰D(260,460nm)以及EPS的EEM图谱中色氨酸荧光峰B的荧光强度随冲击盐度的提升而增加,EPS的EEM图谱中类胡敏酸C峰的荧光强度则随冲击盐度的提升而下降.用平行因子分析(PARAFAC)方法确定EEM图谱中存在的4个组分,分别为类蛋白质组分C1(230/280,350nm),类胡敏酸组分C2(290/310,380nm)、C3(290/360,460nm)和C4(270/340,440nm);当冲击盐度大于2.5g/L时,SMP中C1、C3和C4组分的荧光强度与冲击盐度呈正相关,而EPS中C3和C4组分的荧光强度分别与冲击盐度呈正相关和负相关,其相关系数均≥0.90;SMP中类蛋白质荧光组分和类胡敏酸组分的荧光强度之和分别与测定的蛋白质含量和胡敏酸含量呈明显的正相关性,相关系数均>0.93,可作为荧光组分强度定量计算的依据,而EPS中此相关性并不明显.  相似文献   
568.
中国PM2.5跨区域传输特征数值模拟研究   总被引:56,自引:0,他引:56  
基于CAMx空气质量模型的颗粒物来源追踪技术(PSAT)定量模拟了全国PM2.5及其化学组分的跨区域输送规律,建立了全国31个省市(源)向333个地级城市(受体)的PM2.5及其化学组分传输矩阵.基于此传输矩阵,从区域、省、城市3个空间尺度解析了PM2.5及其主要组分,包括一次PM2.5、硫酸盐、硝酸盐和铵盐的空间来源.结果表明,跨区域传输对重点区域、省及京津冀典型城市的PM2.5污染均有显著贡献,其中京津冀、长江三角洲、珠江三角洲区域及成渝城市群PM2.5年均浓度受区域外省市的贡献分别达到22%、37%、28%、14%;海南、上海、江苏、浙江、吉林、江西等省PM2.5年均浓度受省外源贡献超过45%;北京、天津、石家庄PM2.5年均浓度受省外源影响分别达到37%、42%、33%.  相似文献   
569.
ABSTRACT

The application of a sustainable tourism management and development framework, including the enhancement of cultural heritage is presented for the city of Nafpaktos (Western Greece) and the surrounding area. Through a qualitative SWOT analysis and a quantitative Limits of Acceptable Change (LAC)–Tourism Carrying Capacity (TCC) framework, an attempt is made to establish thresholds, monitor current conditions, and upgrade tourism activities, with simultaneous development of the tourism-associated economic sectors and the cultural heritage of the city. Activity zones are identified and 18 indicators are selected to describe the environmental/cultural, economic, and social conditions of the area. Reference conditions for each indicator are established either as measured or negotiated thresholds and indicators are accordingly scored to depict the current divergence from reference. The Leopold matrix is used to compare scores and identify restrictions of development. Results reveal high potential for sustainable tourism development of the area, as 9 of 18 indicators received high scores, indicating sustainable conditions, and a variety of underdeveloped tourism endpoints were identified, including the castle of the city, which could potentially support a 90-fold increase in tourism flow. However, restricting factors of development were detected, related to the lack of a tourism management plan, the weak on-site protection of the natural and cultural heritage and the lack of awareness for sustainability among the local people. A strategic plan is finally proposed to provide managers, stakeholders, and the local communities with a guiding framework to upgrade the tourism flow in and around the city within a step-by-step sustainable process.  相似文献   
570.
利用三维荧光光谱(EMMs),并结合平行因子分析法,研究了蠡湖水体中有色可溶性有机物(CDOM)的分布特征及其来源,并探讨了不同组分荧光强度与其他水质因子间的相关性.结果表明,蠡湖水体中CDOM主要由2个荧光组分组成,分别为类色氨酸荧光组分C1(225,280/335)和类腐殖质荧光组分C2(250,300/435),并且C1和C2对总荧光强度的贡献率分别75.70%和24.30%.空间上C1和C2荧光强度自东向西依次递减,呈现东蠡湖高于西蠡湖、沿岸区高于湖心区的趋势.荧光指数(FI)、生物源指数(BIX)和腐殖化指数(HIX)都显示蠡湖水体CDOM来源于自生微生物、藻类等新近自生源,整体呈现弱腐殖质特征.相关性分析表明,CDOM与N、P元素的迁移转化密切相关,并且对透明度有重要影响.  相似文献   
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