source analysis

来源分析
  • 文章类型: Journal Article
    镜像视觉反馈(MVF)引起的手部运动错觉在慢性疼痛患者中产生有益效果。然而,这些影响的神经生理机制尚不清楚。在这项初步研究中,我们检验了新的假设,即这种MVF诱导的运动错觉可能通过改变与疼痛处理相关的中线皮质区域的活动来发挥其作用.将具有单独固定强度的电刺激施加到健康成年人的左手,以在具有这种MVF错觉的单侧右手运动以及没有MVF的右手和双侧手运动期间产生疼痛和非疼痛的感觉。在这些事件中,从64个头皮电极记录脑电图(EEG)活动。EEGα节律(8-12Hz)的事件相关失步(ERD)索引了诱导皮层激活的神经生理振荡机制。与痛苦的感觉相比,非疼痛感觉的具体特征是(1)在皮质中线估计较低的αERD,角回,在具有MVF的实验条件下和外侧顶叶区域,以及(2)在没有MVF的控制条件下在外侧前额叶和顶叶区域估计的较高αERD。这些初步结果表明,MVF引起的运动错觉可能会影响伤害感受和神经生理振荡机制,减少皮层边缘和默认模式区域的激活。
    Mirror Visual Feedback (MVF)-induced illusion of hand movements produces beneficial effects in patients with chronic pain. However, neurophysiological mechanisms underlying these effects are poorly known. In this preliminary study, we test the novel hypothesis that such an MVF-induced movement illusion may exert its effects by changing the activity in midline cortical areas associated with pain processing. Electrical stimuli with individually fixed intensity were applied to the left hand of healthy adults to produce painful and non-painful sensations during unilateral right-hand movements with such an MVF illusion and right and bilateral hand movements without MVF. During these events, electroencephalographic (EEG) activity was recorded from 64 scalp electrodes. Event-related desynchronization (ERD) of EEG alpha rhythms (8-12 Hz) indexed the neurophysiological oscillatory mechanisms inducing cortical activation. Compared to the painful sensations, the non-painful sensations were specifically characterized by (1) lower alpha ERD estimated in the cortical midline, angular gyrus, and lateral parietal regions during the experimental condition with MVF and (2) higher alpha ERD estimated in the lateral prefrontal and parietal regions during the control conditions without MVF. These preliminary results suggest that the MVF-induced movement illusion may affect nociception and neurophysiological oscillatory mechanisms, reducing the activation in cortical limbic and default mode regions.
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  • 文章类型: Journal Article
    中国“双碳”计划的目标是实施一系列空气污染政策,以减少含碳颗粒物(PM)的排放。随着邯郸市碳减排工作的改善,中国,在2016年至2020年的冬季收集了细颗粒物(PM2.5),以表征PM2.5中含碳成分的浓度和来源。趋势分析表明,有机碳(OC)和元素碳(EC)浓度均显着降低。PM2.5中总碳气溶胶(TCA)的比例下降了47.0%,强调有效减少碳排放。2016年(12.86±14.10μg·m-3)至2018年(36.76±21.59μg·m-3)次级有机碳浓度逐渐升高,随后逐渐下降。从2018年到2020年,SOC/OC大于67.0%,这意味着需要对碳质气溶胶和挥发性有机化合物(VOC)采取更有效的协同减排措施。在2016年至2020年的冬季,在轻度/中度污染期(LP)和重度/重度污染期(HP)下,初级有机碳(POC)浓度分别降低了76.1%和87.6%。分别。在低压和高压条件下,TCA/PM2.5呈下降趋势,分别下降42.1%和54.7%,分别。来源分析表明,含碳成分主要来自生物质燃烧,2016年和2020年冬季的煤炭燃烧和汽车尾气排放。OC/EC和K+/EC分析指出,下一阶段减少空气污染物的措施应集中在整流生物质燃料上。与2016年相比,2020年汽车尾气排放的贡献有所下降。由于对汽车尾气排放的控制措施,OC和EC浓度下降。
    The goals of the \"dual carbon\" program in China are to implement a series of air pollution policies to reduce the emission of carbon-bearing particulate matter (PM). Following improvements in the reduction in carbon emissions in Handan City, China, fine particulate matter (PM2.5) was collected in the winters from 2016 to 2020 to characterize the concentrations and sources of carbonaceous components in PM2.5. Trend analysis revealed that both organic carbon (OC) and elemental carbon (EC) concentrations significantly decreased. The proportion of total carbon aerosol (TCA) in PM2.5 decreased by 47.0%, highlighting the effective reduction in carbon emissions. Secondary organic carbon (SOC) concentrations increased from 2016 (12.86 ± 14.10 μg·m-3) to 2018 (36.76 ± 21.59 μg·m-3) and then declined gradually. SOC/OC was larger than 67.0% from 2018 to 2020, implying that more effective synergistic emission reduction measures for carbonaceous aerosol and volatile organic compounds (VOCs) were needed. In the winters from 2016 to 2020, primary organic carbon (POC) concentrations reduced by 76.1% and 87.6% under a light/moderate pollution period (LP) and heavy/severe pollution periods (HPs), respectively. The TCA/PM2.5 showed a decreasing trend under LP and HP conditions, decreasing by 42.1% and 54.7%, respectively. Source analysis revealed that carbonaceous components were mainly from biomass burning, coal combustion and automotive exhaust emissions in the winters of 2016 and 2020. OC/EC and K+/EC analysis pointed out that air pollutant reduction measurements should focus on rectification biomass fuels in the next stage. Compared with 2016, the contributions of automotive exhaust emissions decreased in 2020. OC and EC concentrations decreased due to control measures on automotive exhaust emissions.
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  • 文章类型: Journal Article
    在黑色页岩风化过程中,多种重金属元素集中在土壤中,造成污染。本研究选择了高地质背景区的土壤和黑色页岩基岩样品,采用空间分析方法研究了基岩对重金属元素污染的控制。研究结果表明,黑色页岩基岩中重金属含量极高,范围为岩石重金属元素背景值的2.3~13.1倍。风化形成的土壤中重金属含量与基岩呈正相关,范围从1.1到21.3倍的背景值。岩石样品的变异系数范围为1.09至7.18,表明差异很大。分析表明,纯岩对重金属元素的控制能力主要是中等和高,占70%以上,d是受影响最大的金属元素。除了As,其他七个元素表现出强的空间自相关性,区域分布特征明显。土壤元素表现出高均匀性,黑色页岩基岩中的重金属元素主要通过风化释放,是这些元素的主要来源。
    During the process of black shale weathering, multiple heavy metal elements are concentrated in the soil, causing pollution. This study selected soil and black shale bedrock samples from high geological background areas to investigate the control of heavy metal element pollution by bedrock using spatial analysis. The research results indicate that the heavy metal content in black shale bedrock is extremely high, ranging from 2.3 to 13.1 times the background values of rock heavy metal elements. The heavy metal content in the soil formed through weathering is positively correlated with the bedrock, ranging from 1.1 to 21.3 times the background values. The coefficient of variation of rock samples ranges from 1.09 to 7.18, indicating significant variability.The analysis reveals that the control ability of pure rock over heavy metal elements is mainly moderate and high, accounting for over 70 %, with d being the most affected metal element. Except for As, the other seven elements exhibit strong spatial autocorrelation, showing distinct regional distribution characteristics. The soil elements demonstrate high homogeneity, with heavy metal elements from black shale bedrock primarily released through weathering serving as the main source of these elements.
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  • 文章类型: Journal Article
    从三亚市两个最大的旅游岛周边海域采集地表沉积物样品,中国,比较和评估来源,分布,16种多环芳烃(PAHs)的生态风险。PAHs的总浓度范围为31.16至163.3ng/g,平均浓度为102.46ng/g,这仍然低于全球大多数其他沉积物研究中检测到的水平。煤燃烧产生的多环芳烃(流感,Pyr,Fl,Phe)与TOC呈正相关,淤泥,还有粘土,表明这些多环芳烃容易吸附在泥质和粉质沉积物中。三亚湾主要由泥浆和淤泥组成,而海棠湾主要是沙质的。这对应于显著较高浓度的Fl,Phe,与海棠湾相比,三亚湾和皮尔。研究区域的主要工业活动与电力和热力的生产和供应有关。结果表明,重工业生产过程中,沉积物PAHs的主要来源是高温燃烧,其次是海运和石油来源。总的来说,研究区域的多环芳烃污染水平从轻度到中度不等。沉积物质量评估表明,只有Ace和Phe具有较高的个体风险值。三亚湾六站有较高的不利影响风险,在海棠湾,只有HT07对生物影响构成高风险。这两个领域需要加强监测和污染源控制。
    Surface sediment samples were collected from the surrounding sea areas of the two largest tourist islands in Sanya City, China, to compare and assess the sources, distribution, and ecological risks of 16 polycyclic aromatic hydrocarbons (PAHs). The total PAHs concentrations ranged from 31.16 to 163.3 ng/g, with an average concentration of 102.46 ng/g, which is still lower than the levels detected in most other sediment studies worldwide. PAHs from coal combustion (Flu, Pyr, Fl, Phe) showed positive correlations with TOC, Silt, and Clay, indicating that these PAHs are easily adsorbed in muddy and silty sediments. Sanya Bay is primarily composed of mud and silt, whereas Haitang Bay is mainly sandy. This corresponds to the significantly higher concentrations of Fl, Phe, and Pyr in Sanya Bay compared to Haitang Bay. The main industrial activities in the study area are related to power and heat production and supply. The results indicate that the primary sources of sediment PAHs are high-temperature combustion during heavy industrial production, followed by maritime transportation and petroleum sources. Overall, the PAHs pollution levels in the study area range from slight to moderate. Sediment quality assessments show that only Ace and Phe have higher individual risk values. Six stations in Sanya Bay have higher adverse impact risks, while in Haitang Bay, only HT07 poses a high risk to biological impact. These two areas require enhanced monitoring and pollution source control.
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  • 文章类型: English Abstract
    基于2021年6月16-26日济南市一次典型的臭氧(O3)污染过程,研究了不同污染时期(清洁期(CP),污染上升期(PRP),重污染期(HPP),分析了城市区域的污染衰退期(PDP)。采用正矩阵分解(PMF)和基于观测的模型(OBM)来识别VOCs的主要来源,O3生产机制,敏感物种。结果表明,市区HPP期ρ(O3-8h)平均值为(246.67±11.24)μg·m-3,ρ(O3-1h)峰值为300μg·m-3。VOCs的体积分数和NO2浓度受行星边界层和风速降低的影响,分别比其他三个时期高76.99%-145.36%和127.78%-141.18%,分别,是O3污染加剧的主要原因。烷烃,含氧挥发性有机化合物(OVOCs),卤代烃占43.81%,20.98%,城市地区的VOCs占17.43%,分别。在HPP期间,它们都表现出显著的增长,用丙酮,丙烷,乙烷是每个阶段中体积最高的三个物种,异戊烷在HPP期间表现出最高的生长。烯烃,烷烃,芳烃占40.19%,28.06%,臭氧产生潜力(OFP)的21.92%。1-丁烯,甲苯,异戊烷,异戊二烯是OFP含量较高的物种。异戊二烯在PRP阶段的OFP最高,和1-丁烯在HPP阶段具有最高的OFP。异戊烷的体积分数显著增加OFP。VOCs与CO的相关系数初步表明机动车尾气和油气挥发是HPP期VOCs的主要来源。进一步使用PMF表明溶剂使用来源,燃烧源,机动车尾气+油气挥发源,工业排放源,植物来源是城市地区VOCs的重要来源。HPP时期机动车尾气+油气挥发源对VOCs的贡献为其他时期的3.09-14.72倍。溶剂使用来源对VOC的贡献比CP和PRP时期高约2.50倍。VOCs体积分数增加的主要来源是机动车尾气,油气挥发源,和溶剂使用来源。潜在来源和浓度权重分析发现,VOCs也受到东北向滨州和东营的VOCs传播的影响。OBM结果表明,城市地区O3形成的主要途径是过氧化物羟基自由基(HO2·)和甲基过氧化物自由基(CH3O2·)与NO的反应。HPP阶段[P(O3)净]臭氧净生成速率为24×10-9h-1。根据灵敏度实验结果,1-丁烯的烯烃组分,丙烯,顺式-2-丁烯,乙烯是O3生产的主要物种。
    Based on a typical ozone (O3) pollution process in Jinan City from June 16 to 26, 2021, the variation characteristics of O3 and its precursor volatile organic compounds (VOCs) during different pollution periods (clean period (CP), pollution rise period (PRP), heavy pollution period (HPP), and pollution decline period (PDP)) in the urban area were analyzed. Both positive matrix factorization (PMF) and an observation-based model (OBM) were used to identify the main sources of VOCs, O3 production mechanisms, and sensitive species. The results showed that the average value of ρ(O3-8h) during the HPP period in the urban area was (246.67±11.24) μg·m-3, and ρ(O3-1h) had a peak value of 300 μg·m-3. The volume fractions of VOCs and NO2 concentration were affected by the decrease in planetary boundary layer and wind speed, which were 76.99%-145.36% and 127.78%-141.18% higher than those in the other three periods, respectively, and were the main reasons for the aggravation of O3 pollution. Alkanes, oxygenated volatile organic compounds (OVOCs), and halogenated hydrocarbons accounted for 43.81%, 20.98%, and 17.43% of VOCs in urban areas, respectively. All of them showed significant growth during the HPP period, with acetone, propane, and ethane being the top three species by volume in each stage and isopentane showing the highest growth during the HPP period. Alkene, alkanes, and aromatic hydrocarbons accounted for 40.19%, 28.06%, and 21.92% of the ozone generation potential (OFP). 1-butene, toluene, isopentane, and isoprene were the species with higher OFP. Isoprene had the highest OFP during the PRP phase, and 1-butene had the highest OFP during the HPP phase. The volume fraction of isopentane significantly increased OFP. The correlation coefficient between VOCs and CO preliminarily indicated that motor vehicle exhaust and oil and gas volatilization were the main sources of VOCs during the HPP period. Further use of PMF revealed that solvent use sources, combustion sources, motor vehicle exhaust+oil and gas volatilization sources, industrial emission sources, and plant sources were important sources of VOCs in urban areas. The contribution of motor vehicle exhaust+oil and gas volatilization sources in the HPP period to VOCs was 3.09-14.72 times higher than that in other periods. The contribution of solvent use sources to VOCs was approximately 2.50 times higher than that in the CP and PRP periods. The main sources of VOCs volume fraction increase were motor vehicle exhaust, oil and gas volatilization sources, and solvent use sources. Potential sources and concentration weight analysis found that VOCs were also affected by the transmission of VOCs to Binzhou and Dongying in the northeast direction. The OBM results indicated that the main pathway of O3 formation in urban areas was the reaction of peroxide hydroxyl radicals (HO2·) and methyl peroxide radicals (CH3O2·) with NO, and the net ozone generation rate during the HPP phase [P(O3)net] was 24×10-9 h-1. Based on the sensitivity experiment results, the alkene components of 1-butene, propylene, cis-2-butene, and ethylene were the dominant species for O3 production.
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  • 文章类型: English Abstract
    关中城市群具有良好的发展基础和巨大的发展潜力,在国家全方位对外开放格局中具有独特的战略地位。近年来,关中地区近地表臭氧(O3)问题日益突出,成为影响空气质量持续改善的瓶颈。为了有效防治O3污染,本研究分析了年度特征,每月,和基于2018-2021年环境监测数据的关中地区O3浓度日变化。使用地质探测器研究了O3浓度空间差异的驱动因素,并使用反向轨迹模型和排放清单构建分析了O3的来源。结果表明,关中地区O3浓度的日变化和月变化是单峰的。日最大值出现在15:00,最小值出现在07:00,月平均值的峰值出现在6月,谷值出现在12月。O3浓度在夏季最高,接下来是春天,冬季最低。O3超标天数主要表现为轻度污染,中度及以上污染呈现先减少后增加的趋势。关中地区O3浓度主要与前兆和气象因素密切相关,各因素交互作用的解释力显著大于任何单因素。关中地区O3浓度的区域输送主要受偏东气流的影响,然后是西北方向,潜在源区主要分布在河南省和湖北省。当地挥发性有机化合物(VOCs)的主要来源是溶剂使用来源,过程源,和移动源,氮氧化物(NOx)的主要排放源是移动源和工业生产燃烧源。研究结果对关中地区O3联防联控具有指导意义。
    Guanzhong urban agglomeration has a good development foundation and great development potential, and it has a unique strategic position in the national all-round opening up pattern. In recent years, the problem of near-surface ozone (O3) in the Guanzhong Region has become increasingly prominent, which has become a bottleneck affecting the continuous improvement of air quality. In order to effectively prevent and control O3 pollution, this study analyzed the characteristics of annual, monthly, and daily changes in O3 concentration in the Guanzhong Region based on the environmental monitoring data from 2018 to 2021. A geo-detector was used to study the driving factors of the spatial differentiation of O3 concentration, and the sources of O3 were analyzed using a backward trajectory model and emission inventory construction. The results showed that the daily and monthly variation in O3 concentration in the Guanzhong Region were unimodal. The daily maximum value appeared at 15:00, the minimum value appeared at 07:00, the peak value of the monthly average appeared in June, and the valley value appeared in December. The O3 concentration was highest in summer, followed by that in spring, and the lowest in winter. The days of O3 exceeding the standard showed mainly mild pollution, and moderate and above pollution showed a trend of decreasing first and then increasing. The O3 concentration in the Guanzhong Region was mainly closely related to precursors and meteorological factors, and the explanatory power of the interaction of each factor was significantly greater than that of any single factor. The regional transport of O3 concentration in the Guanzhong Region was mainly affected by easterly airflow, followed by the northwest direction, with the potential source areas located mainly in Henan Province and Hubei Province. The main local sources of volatile organic compounds (VOCs) were solvent use sources, process sources, and mobile sources, and the main emission sources of nitrogen oxides (NOx) were mobile sources and industrial production combustion sources. The research results have a guiding significance for O3 joint prevention and control in the Guanzhong Region.
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  • 文章类型: Journal Article
    废弃采煤区的长期采煤活动,导致大量重金属向周围土壤环境迁移,对区域生态环境造成威胁。这项研究的重点是从典型的废弃煤矿区收集的地表土壤。采用污染指数(PI)和潜在生态风险指数(RI)等方法对土壤重金属污染水平和生态风险进行综合评价。利用地统计学分析和APCS-MLR模型对土壤重金属的来源进行了量化,和内梅罗综合生态风险(NIRI)模型耦合分配不同污染源的生态风险。结果表明,As,Zn分别是土壤背景值的4.58、2.44和1.67倍,分别,而其他重金属的浓度低于土壤背景值。研究区的土壤受到重金属的强烈污染,Cd的污染水平和生态风险显著高于其他重金属。NIRI计算结果表明,总体综合生态风险水平相当,样本点被归类为相对可观的,中度,低至60.53%,36.84%,和2.63%,分别。土壤重金属的来源可以分为四种类型:交通活动,自然来源,煤矸石堆积,以及煤炭开采和农业活动的综合来源,贡献率为35.3%,36.1%,19.5%,和9.1%,分别。具体来源生态风险评价结果表明,煤矸石堆积物对生态风险的贡献最大(36.4%),应优先进行污染治理。Cd是生态风险的优先控制元素。研究结果为废弃煤矿区土壤重金属污染的精细化管理提供了理论支持。
    Long-term coal mining activities in abandoned coal mining areas have resulted in the migration of large quantities of heavy metals into the surrounding soil environment, posing a threat to the regional ecological environment. This study focuses on the surface soil collected from a typical abandoned coal mining area. Methods such as the pollution index (PI) and potential ecological risk index (RI) were used to comprehensively evaluate the pollution levels and ecological risks of soil heavy metals. Geostatistical analysis and the APCS-MLR model were used to quantify the sources of soil heavy metals, and Nemerow integrated ecological risk (NIRI) model was coupled to apportion the ecological risks from different pollution sources. The results indicate that the average concentrations of Cd, As, and Zn are 4.58, 2.44, and 1.67 times the soil background values, respectively, while the concentrations of other heavy metals are below the soil background values. The soil of study area is strongly polluted by heavy metals, with the pollution level and ecological risk of Cd being significantly higher than those of other heavy metals. The NIRI calculation results show that the overall comprehensive ecological risk level is considerable, with sample points classified as relatively considerable, moderate, and low at 60.53 %, 36.84 %, and 2.63 %, respectively. The sources of soil heavy metals can be categorized into four types: traffic activities, natural sources, coal gangue accumulation, and a combined source of coal mining and agricultural activities, with contribution rates of 35.3 %, 36.1 %, 19.5 %, and 9.1 %, respectively. The specific source ecological risk assessment results indicate that coal gangue accumulation contributes the most to ecological risk (36.4 %) and should be prioritized for pollution control, with Cd being the priority control element for ecological risk. The findings provide theoretical support for the refined management of soil heavy metal pollution in abandoned coal mining areas.
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  • 文章类型: Journal Article
    土壤环境在城市生态系统中起着重要作用。为研究北仑区土壤重金属污染,宁波,我们收集了北仑区市区和城郊地区60个点的土壤样品,并分析了各种土地利用类型中重金属污染的时空变化和来源。结果表明,2015年和2022年宁波市土壤重金属含量均高于本底,在这7年里有重金属的积累。2022年绿化带和林地重金属含量均高于2015年,而农用地则无明显变化。两年的重金属含量主要按照绿化带>农用地>林地的顺序。重金属含量的时空分布表明,北仑区重金属污染集中在五个工业区,并且有高度污染点消失的趋势。但是单因子污染指数,污染负荷指数(PLI),和地质累积指数(Igeo)表明,北仑区没有明显的重金属污染,个别元素在特定点表现出轻微的污染。源分析结果表明,汞的主要来源是化学,主要来自农业,Cr,Ni和Cu主要来自天然,锌和镉的主要来源是电镀和机械活动,铅的主要来源是交通。这些结果为未来城市土壤重金属调查提供了参考,源解析结果为后续土壤重金属污染治理提供科学依据。
    The soil environment plays an important role in urban ecosystems. To study the heavy metal contamination of soil in Beilun District, Ningbo, we collected soil samples from 60 points in urban and peri-urban areas of Beilun District and analyzed the spatiotemporal variation and sources of heavy metal pollution in various land-use types. The results shown that the heavy metal contents in 2015 and 2022 were higher than the background soil values of Ningbo city, and there was an accumulation of heavy metals over these 7 years. The contents of heavy metals in green belts and woodland in 2022 were higher than those in 2015, while there was no significant change in agricultural land. The heavy metal contents in both years were mainly in the order green belts > agricultural land > woodland. The spatiotemporal distribution of heavy metal content showed that heavy metal pollution in Beilun District was concentrated in five industrial areas, and there was a trend toward the disappearance of highly polluted points. But the single-factor pollution index, pollution load index (PLI), and geoaccumulation index (Igeo) indicated that there was no significant heavy metal pollution in Beilun District, and individual elements at specific points showed slight pollution. The source analysis results showed that the main source of Hg is chemical, As is mainly derived from agricultural, Cr, Ni and Cu are mainly derived from natural, the main sources of Zn and Cd are electroplating and machinery activities, and the main source of Pb is traffic. These results specify a reference for future investigation on urban soil heavy metals, and the source apportionment results provide a scientific foundation for subsequent soil heavy metal pollution treatment.
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  • 文章类型: Journal Article
    放射性核素铯(Cs)和锶(Sr)具有较长的半衰期,135Cs约为230万年,87Sr约为490亿年。它们的持续积累会导致土壤生态系统的长期放射性污染。本研究采用地质累积指数(Igeo),污染负荷指数(PLI),潜在生态风险指数(PEPI),健康风险评估模型(HRA),和蒙特卡洛模拟评价了中国典型矿业城市不同功能区表层土壤中Cs和Sr的污染和健康风险。正矩阵分解(PMF)模型用于阐明Cs和Sr的潜在来源以及自然和人为来源的各自贡献率。结果表明,与冶炼厂区相比,矿区土壤中的Cs和Sr污染水平明显更高,农业区,和城市居住区。在任何研究的功能区中,锶都不会构成潜在的生态风险。研究区域Sr对人体的非致癌健康风险相对较低。由于缺少Cs的参数,未计算Cs的潜在生态和人类健康风险。土壤中Cs的主要来源被确定为土壤发育的母体材料,而Sr主要来自采矿活动造成的相关污染。该研究为矿业城市表层土壤中Cs和Sr污染的控制提供了数据。
    Radioactive nuclides cesium (Cs) and strontium (Sr) possess long half-lives, with 135Cs at approximately 2.3 million years and 87Sr at about 49 billion years. Their persistent accumulation can result in long-lasting radioactive contamination of soil ecosystems. This study employed geo-accumulation index (Igeo), pollution load index (PLI), potential ecological risk index (PEPI), health risk assessment model (HRA), and Monte Carlo simulation to evaluate the pollution and health risks of Cs and Sr in the surface soil of different functional areas in a typical mining city in China. Positive matrix factorization (PMF) model was used to elucidate the potential sources of Cs and Sr and the respective contribution rates of natural and anthropogenic sources. The findings indicate that soils in the mining area exhibited significantly higher levels of Cs and Sr pollution compared to smelting factory area, agricultural area, and urban residential area. Strontium did not pose a potential ecological risk in any studied functional area. The non-carcinogenic health risk of Sr to the human body in the study area was relatively low. Because of the lack of parameters for Cs, the potential ecological and human health risks of Cs was not calculated. The primary source of Cs in the soil was identified as the parent material from which the soil developed, while Sr mainly originated from associated contamination caused by mining activities. This research provides data for the control of Cs and Sr pollution in the surface soil of mining city.
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  • 文章类型: English Abstract
    探讨川南城市群冬季重污染PM2.5中金属元素的浓度特征及来源(自贡,泸州,内江,和宜宾),于2018年12月30日至2019年1月14日采用膜采样方法测定PM2.5中的金属元素,并应用富集因子法(EF)和正矩阵分解法(PMF)对金属元素的来源进行调查.利用自贡市2015年同期的金属元素观测数据,考察了《中国大气污染防治行动计划》实施中后期自贡市金属元素污染和富集变化情况。主要研究结果如下:①不同城市颗粒物中金属元素的浓度和百分比差异不显著。四个城市中浓度较高的元素表现出相似性,Al,Sb,Fe在顶部。从自贡不同观测时期的比较来看,除Tl以外的所有元素的浓度发生变化。②富集因子计算结果表明,元素Cr的富集(自贡和宜宾),Ni,Cu,As,Se,Ag,Cd,Sb,Tl,城市群中铅较高。自贡不同观测时期元素富集水平的比较表明,除了铜,2018年冬季观察期呈下降趋势。③PMF来源分析结果表明,各城市的金属元素主要来源于粉尘源,燃煤来源,工业来源,和交通来源,而来源之间的贡献参差不齐。主要来源的贡献在城市之间有所不同,自贡以交通粉尘源和混合源为主,泸州以工业资源为主,内江有来自不同来源的类似贡献,宜宾以交通来源为主。
    To investigate the concentration characteristics and sources of metal elements in PM2.5 during winter heavy pollution in the southern Sichuan urban agglomeration (Zigong, Luzhou, Neijiang, and Yibin), the metal elements in PM2.5 were measured using membrane sampling methods from December 30, 2018 to January 14, 2019, and the enrichment factor method (EF) and positive matrix factorization(PMF) were applied to investigate the sources of metal elements. The metal element observation data of Zigong in the same period of 2015 were also used to investigate the changes in metal element pollution and enrichment in Zigong in the middle and end of the implementation of China\'s Air Pollution Prevention and Control Action Plan. The main findings were as follows:① The concentrations and percentages of metal elements in particulate matter in different cities did not differ significantly. The elements with higher concentrations in the four cities showed similarities, with Al, Sb, and Fe at the top. From the comparison of different observation periods in Zigong, the concentrations of all elements except Tl changed. ② The results of the enrichment factor calculation showed that the enrichment of the elements Cr (Zigong and Yibin), Ni, Cu, As, Se, Ag, Cd, Sb, Tl, and Pb in the urban agglomeration was high. The comparison of the enrichment levels of elements in Zigong for different observation periods showed that the enrichment levels of all elements, except Cu, tended to decrease in the winter observation period of 2018. ③ The results of PMF source analysis showed that the metal elements in each city mainly originated from dust sources, coal-fired sources, industrial sources, and traffic sources, whereas there was a mixed contribution among the sources. The contribution of the main sources differed among cities, in which Zigong was dominated by traffic dust sources and mixed sources, Luzhou was dominated by industrial sources, Neijiang had a similar contribution from different sources, and Yibin was dominated by traffic sources.
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