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1.
The present study was conducted to assess the suitability of sewage sludge amendment (SSA) in soil for Beta vulgaris var. saccharifera (sugar beet) by evaluating the heavy metal accumulation and physiological responses of plants grown at a 10%, 25%, and 50% sewage sludge amendment rate. The sewage sludge amendment was modified by the physicochemical properties of soil, thus increasing the availability of heavy metals in the soil and consequently increasing accumulation in plant parts. Cd, Pb, Ni, and Cu concentrations in roots were significantly higher in plants grown at 25% as compared to 50% SSA; however, Cr and Zn concentration was higher at 50% than 25% SSA. The concentrations of heavy metal showed a trend of Zn > Ni > Cu > Cr > Pb > Cd in roots and Zn > Cu > Ni > Cr > Pb > Cd in leaves. The only instance in which the chlorophyll content did not increase after the sewage sludge treatments was 50%. There were approximately 1.12-fold differences between the control and 50% sewage sludge application for chlorophyll content. The sewage sludge amendment led to a significant increase in Pb, Cr, Cd, Cu, Zn, and Ni concentrations of the soil. The heavy metal accumulation in the soil after the treatments did not exceed the limits for the land application of sewage sludge recommended by the US Environmental Protection Agency (US EPA). The increased concentration of heavy metals in the soil due to the sewage sludge amendment led to increases in heavy metal uptake and the leaf and root concentrations of Ni, Zn, Cd, Cu, Cr, Pb, and Zn in plants as compared to those grown on unamended soil. More accumulation occurred in roots and leaves than in shoots for most of the heavy metals. The concentrations of Cd, Cr, and Pb were more than the permissible limits of national standards in the edible portion of sugar beet grown on different sewage sludge amendment ratios. The study concludes that the sewage sludge amendment in the soil for growing sugar beet may not be a good option due to risk of contamination of Cr, Pb, and Cd.  相似文献   

2.
为探索刺楸对受污染土壤重金属的富集和修复效应, 以南京栖霞山的乡土树种刺楸及其根际周边土壤为研究对象, 截取其根基部年轮盘及根际土壤样本, 采用ICP-AES法测定年轮及土壤样本中重金属(Cu、Cd、Cr、Mn、Ni、Pb、Zn)元素含量。结果表明: 栖霞山样地中的土壤受Mn、Pb和Zn污染最为严重, 存在Cu、Cd、Mn、Pb、Zn元素的高度复合污染, Cd、Cr、Cu、Ni、Zn在土壤和年轮中存在相关性, Mn和Pb则没有表现出明显的相关性; 刺楸修复受Cd、Mn、Pb、Zn污染的土壤效果并不显著, 更适用于Cr、Cu、Ni污染的土壤修复; 鉴于Cu元素含量变化特征, 刺楸也可以作为反映当地污染历史的记录载体; 刺楸年轮中的重金属元素之间存在交互作用, 其中Cd与Zn元素含量高度相关(r=0.984, p<0.01), 在刺楸年轮吸收重金属元素的过程中, Cu与Cd、Cr、Mn、Zn元素具有协同作用, Mn元素对其他元素有一定的拮抗作用。  相似文献   

3.
强还原过程对设施菜地土壤重金属形态转化的影响   总被引:1,自引:0,他引:1  
设施菜地由于污水灌溉、粪肥施用等导致重金属污染.本文通过土柱淹水同时添加玉米秸秆培养和后期通水淋洗,研究强还原法对设施土壤重金属(Cd、Cu、Pb和Zn)形态转化的影响.结果表明: 强还原处理使土壤pH显著降低,玉米秸秆处理变化更显著;土壤氧化还原电位(Eh)迅速下降至-280 mV左右.玉米秸秆处理可以促进土壤中Cd、Cu、Pb和Zn活化,第9天土壤中有机物及硫化物结合态和残渣态Cd、Cu、Pb和Zn含量比重下降;至15 d培养结束,土壤中4种重金属含量较对照分别减少18.1%、19.0%、16.1%和15.7%.玉米秸秆处理可以增加土壤中Cd和Zn的溶出量,但是Cu的溶出量减少;胶体结合态Cd和Pb含量较对照增加、Cu较对照显著减少、Zn没有显著变化.强还原可以引起设施土壤重金属活化,提高蔬菜积累重金属的风险,而且其随土壤水分的运移可能导致水体的污染.  相似文献   

4.
To identify sources of heavy metal(loid) (HM) contamination in agricultural soils of Huzhou, surface soil samples were sampled from 89 different agricultural regions in 2012. Concentrations of heavy metal(loid)s, along with pH, total phosphorus (TP), total nitrogen (TN), and soil organic matter (SOM), were determined. Ecological risk was then assessed using a modified Hakanson ecological risk index, and the sources of contamination were determined using principal component analysis (PCA). Mean concentrations of heavy metal(loid)s were 10.26, 23.21, 83.75, 22.81, 0.25, 61.86, 33.03, and 0.15 mg kg?1 for As, Cu, Zn, Ni, Cd, Cr, Pb, and Hg, respectively. Cu, Zn, Ni, Cr, Cd, Hg, and Pb were correlated positively with TP and there were obvious positive correlations among Cu, Zn, Ni, Cr, and Cd. Risk index (RI) values varied from 39 to 1246 with a mean value of 137. Enrichment of Pb, Zn, Cu, and especially Cd can be attributed to excessive use of nitrogen and phosphorus fertilizers containing heavy metals, as well to surface irrigation and natural soil formation. While the ecological risk of most agricultural soils in Huzhou is low, it is recommended that the use of phosphate and nitrogen fertilizers be restricted and production technology be improved to reduce the heavy metal(loid) concentrations. Results suggest that the Chinese environmental quality standard for soil should be revised to better address heavy metal(loid) contamination.  相似文献   

5.
This study assessed the concentrations of five heavy metals Pb, Cd, Cr, Cu and Zn in both soil and a traditional Chinese medicine Cortex Moutan collected from 6 typical sites, growing this medicine, in China. The potential health risks associated with those heavy metals were also assessed. It is shown that Cd content in soils from five of the six sites was higher than the environmental Quality Standard for Soils of China (EQSS). The cortex from a copper tailings area in Tongling (marked as TLC) accumulated much higher amounts of heavy metals than the other sites. Calculated pollution index implied that the herbs in TLC were mildly contaminated by Pb, Cd, and Cu. Hazard quotient (HQ) indicated the intake of Pb, Cd, Cr, Cu, and Zn was safe by cortex consumption, but noncarcinogenic and carcinogenic risks of all metals in Cortex Moutan in hillside near the copper tailings (marked as TLB) and TLC were higher. The results suggested more attention should be paid to the planting area near the mining tailing, and in order to ensure the quality of the herbal medicines, the regions where this herb is grown should be at distance from the mining tailing area.  相似文献   

6.
Due to rapid industrialization and urbanization during the last two decades, contamination of urban agricultural soils by heavy metals is on an increase all over China. In this study, fifty soil samples were collected from urban vegetable fields in a chemical industrial area and non chemical industrial area in Jilin City to investigate the heavy metal pollution level. The mean Pb, Cr, Cu, Ni, Zn, and Cd contents (30.84, 65.65, 26.41, 23.07, 135.14, and 0.1434 mg kg?1 dry weight, respectively) in the urban vegetable soils were higher than their corresponding natural background values. The principal component analysis (PCA) was performed to identify the possible sources of metal contamination in the study area. The results indicated that Cu and Zn were mainly from industrial activities, while Pb and Cd were derived from traffic activities and agricultural activities, and Cr and Ni tended to be from parent material. The distribution of comprehensive pollution index values showed that Pb, Cr, Cu, Ni, Zn, and Cd concentrations in most of the agricultural fields did not exceed the baseline values affecting the safety of agricultural production and human health according to the soil environmental quality standard of China, indicating an insignificant contamination of these metals in Jilin City.  相似文献   

7.
Heavy metal contamination of agricultural soils resulting from rapid industrialization and urbanization is of great concern because of potential health risk due to dietary intake of contaminated vegetables. The present study aims to evaluate the status of heavy metals contamination of agricultural soils and food crops around an urban-industrial region in India. Transfer factor values of Cu, Cr, Pb, Cd, Zn, and Ni from soil to vegetable was estimated. The mean heavy metal concentrations (mg/kg) in agricultural soils (Cu: 17.8, Cr: 27.3, Pb: 29.8, Cd: 0.43, Zn: 87, Mn: 306.6, Fe: 16984, and Ni: 53.8) were within allowable concentrations for Indian agricultural soil. The concentrations of Pb, Cd, Zn, and Ni in crops/vegetables exceeded the World Health Organization/Food and Agriculture Organization safe limits. Relative orders of transfer of metals from soil to edible parts of the crops/vegetables were Cd > Pb > Ni > Zn > Cu > Cr. The enrichment factors of heavy metals in soil indicated minor to moderately severe enrichment for Pb, Cd, and Ni; minor to moderate enrichment for Zn; no enrichment to minor enrichment for Mn; and no enrichment to moderate enrichment for Cu at different sites. Ecological risk index of soil showed considerable contamination in one of the wastewater irrigated sites.  相似文献   

8.
某农药工业园区周边土壤重金属含量与风险评价   总被引:11,自引:0,他引:11  
Shi NN  Ding YF  Zhao XF  Wang QS 《应用生态学报》2010,21(7):1835-1843
以苏南某农药工业园区周边30km2区域为研究区,采用同心圆法采集土壤样品183个,分析了农药工业园区周边土壤Cd、Cr、Cu、Ni、Pb、Zn、Hg和As8种重金属含量、空间变异性、来源及潜在风险.结果表明:以自然背景值为评价标准,研究区表层土壤Hg、Cu、Cd和Pb平均含量超过自然背景值,其中Hg和Cu含量最高;以国标二级标准为评价标准,土壤Cd、Cr、Ni、Pb、Zn、As6种重金属的单项污染指数平均值均小于1,Hg和Cu分别为1.59和1.05.在农药工业园区周边土壤重金属污染较重的东南方向和西北方向,随着与园区距离的增加,土壤Cd、Ni、Pb、Cr、As、Hg、Zn和Cu含量先上升、后下降、再趋于平稳.通过分析农药工业园区周边土壤重金属综合污染指数发现,距离园区约200~1000m周边土壤污染的风险较大,而1000m以外逐渐达到安全范围.利用地统计学和GIS相结合进行分析发现,8种重金属污染指数有明显的空间变异.依据相关分析与主成分分析结果推测,Zn、Ni、Cr、Pb和As主要来源于成土母质,而Hg、Cu和Cd主要与人类活动有关.  相似文献   

9.
The contamination of coal-mine soil by heavy metals is a widespread problem. This study analyzes the heavy metals (Cu, Zn, Ni, Pb, Cr, Cd, and Hg) found in 33 surface soil samples from Xinzhuangzi, China restored coal-mining land used as cultivated land. The results show that the selected elements were cumulative, especially for Cd. An index of geo-accumulation indicates that the soil was practically uncontaminated by Cu, Zn, Ni, and Hg, uncontaminated to moderately contaminated by Pb and Cr, and moderately to heavily contaminated by Cd. Based on the U.S. Environmental Protection Agency's ecological soil screening levels (Eco-SSLs) for Cu, Zn, Ni, Pb, and Cd and the Dutch Target and Intervention Values for Cr and Hg, the plants and soil invertebrates were not likely greatly influenced by the selected metals. Although the Cd concentration was found to have no significant effect on plants and soil invertebrates, it is the only metal with a concentration significantly above that required by Chinese standards (HJ/T 332–2006) for edible agricultural products, indicating that Cd is the predominant factor that determines the use of the reclaimed coal-mining area for farmland. Thus, employing the reclaimed land as farmland may not be a good option.  相似文献   

10.
We studied the distribution of seven heavy metals and As in typical municipal greenbelt roadside soils in Pudong New District, Shanghai, China. As and Ni showed no significant accumulation compared with the background values of the local soils, but there was strong evidence of accumulation of Cd, Cr, Cu, Hg, Pb and Zn in the roadside soils. However, only Zn and Cd contents were higher than the pollution thresholds of the Chinese National Soil Quality standard. The concentrations of heavy metal(loid)s in the soils were significantly affected by the length of time since the roads were constructed. Soils from areas adjacent to an older road had higher levels of Cu, Pb, Cd and Zn. In terms of spatial distribution, more Cd, Cu, Pb and Zn were found in the soil from the green areas of median between carriageways than from those of the roadside verges. Vertical distribution analysis shows that the contents of Pb, Cd, Cu and Zn had maximum values in the topsoil and were substantially lower in the deeper layers of the soil profile. Moreover, correlation analysis reveals that these four heavy metals originated from the same pollution sources and their contents were directly associated with the traffic density.  相似文献   

11.
A total of 195 farmland soil samples were collected in Yanqi Basin, Xinjiang, northwest China, and the concentrations of As, Cd, Cr, Cu, Ni, Pb, and Zn were analyzed for their concentrations and pollution levels using the Nemerow comprehensive index. The health risk assessment model introduced by USEPA was utilized to evaluate the human health risks of heavy metals. Results indicated that the average concentrations of these seven metals were lower than the allowed soil environmental quality standards of China, while the average concentrations of Cd, Cr, Ni, Pb and Zn exceeded the background values of irrigation soils in Xinjiang. The average contamination factor (CF) for Pb indicated the heavy pollution, whereas the CF for Cd, Zn, Ni, Cu and Cr indicated the moderate pollution. The average PLI of heavy metals indicated the low pollution. The non-carcinogenic hazard index were below the threshold values, and the total carcinogenic risks due to As and Cr were within the acceptable range for both children and adults. As and Pb were the main non-carcinogenic factors, while As was the main carcinogenic factor in the study area. Special attentions should be paid to these priority control metals in order to target the lowest threats to human health.  相似文献   

12.
以铜锈环棱螺(Bellamya aeruginosa)为测试生物,采用28 d沉积物生物积累试验研究铜锈环棱螺对污染河流沉积物中重金属的生物积累,并探讨其与重金属赋存形态的关系.结果表明:铜锈环棱螺肝胰脏对Cd、Pb、Cu、Cr、Zn和Mn均具有较强的积累作用.不同重金属的积累量存在较大差别,Zn的积累量最多,占重金属总积累量的84.32%±4.36%,其次为Cu,占7.67%±2.84%;Pb、Cr和Mn的比例相对较少,分别为3.62%±1.84%、2.22%±1.03%和1.33%±0.15%;Cd所占比例最少,为0.83%±0.53%.肝胰脏中重金属元素之间的相关性均不显著.肝胰脏金属污染指数与沉积物污染综合指数具有显著的正相关关系,铜锈环棱螺可以作为沉积物重金属污染的监测生物.不同沉积物Cd、Cr、Zn和Mn的生物-沉积物积累因子(BSAF)具有较大的差异,Cu和Pb的BSAF比较稳定.Cd的生物积累与沉积物中Cd的可交换的与酸可溶态及可氧化态显著相关;Pb的生物积累与Pb的可还原态显著相关;Cu的生物积累与Cu的可氧化态显著相关;Mn的生物积累与Mn的可交换的与酸可溶态和可还原态显著相关;Cr和Mn的生物积累与其不同形态和总量均不相关.BSAF不宜作为衡量铜锈环棱螺对沉积物中重金属生物积累能力的指标.  相似文献   

13.
To assess the extent and potential hazards of heavy metal pollution at Shanghai Laogang Landfill, the largest landfill in China, surface soil samples were collected near the landfill and concentrations of Cu, Zn, Cd, Pb, and Cr were determined. The results revealed that the concentrations of heavy metals, except Pb, were higher in the surface soil near the landfill than in the background soil. Principal component analysis and hierarchical cluster analysis suggested that the enrichment of Cu in soil was probably related to agricultural activities and Cd and Pb to landfill leachates, whereas Zn and Cr concentrations were probably controlled by soil matrix characteristics. The pollution indices (PIs) of the metals were: Cd > Cu > Cr > Zn > Pb. Among the five measured metals, Cd showed the largest toxic response and might cause higher ecological hazards than other metals. The integrated potential eco-risk index (RI) of the five metals ranged from 26.0 to 104.9, suggesting a low-level eco-risk potential. This study indicated the accumulations of Cu, Zn, Cd, Pb, and Cr did not reach high pollution levels, and therefore posed a low eco-risk potential in surface soil near the landfill.  相似文献   

14.
新疆焉耆盆地辣椒地土壤重金属污染及生态风险预警   总被引:5,自引:0,他引:5  
从新疆加工辣椒主产地(焉耆盆地)采集105个辣椒地典型土壤样品,测定其中As、Cd、Cr、Cu、Mn、Ni、Pb和Zn等8种重金属元素的含量。采用污染负荷指数(Pollution load index,PLI)、潜在生态风险指数(Potential ecological risk index,RI)和生态风险预警指数(Ecological risk warning index,I_(ER))对辣椒地土壤重金属污染及生态风险进行评价。结果表明:(1)焉耆盆地辣椒地土壤Cd、Cr、Ni、Pb和Zn含量的平均值分别超出新疆灌耕土背景值的1.65、1.40、1.32、3.21、6.42倍。辣椒地土壤Pb和Zn呈现重度污染,Cd、Cr和Ni轻度污染,As、Mn和Cu无污染。(2)土壤PLI平均值为1.40,呈现轻度污染。各重金属元素单项生态风险指数从大到小依次为:Cd、Ni、As、Cu、Pb、Cr、Zn。土壤RI平均值为18.40,属于轻微生态风险态势,IER平均值为-4.78,属于无警态势;博湖县辣椒地污染水平、潜在生态风险程度与生态风险预警等级最高,焉耆县污染水平、潜在生态风险程度与生态风险预警等级最低。(3)辣椒地土壤As、Cd、Pb与Zn主要受到人类活动的影响,Cr、Cu、Mn和Ni主要受到土壤地球化学作用的控制。Cd是焉耆盆地辣椒地生态风险等级最高的重金属元素,研究区农业生产过程中要防范Cd的污染风险。  相似文献   

15.
In this study, a total of 84 sites in the Luan River Basin of China and its tributaries were monitored in 2012 for seven heavy metals (Cu, Ni, Pb, Zn, Cd, Cr, Hg) in the surface sediments. Cluster analysis (CA), principal component analysis (PCA), correlation analysis, and pollution indices were applied to the interpretation of the monitoring results. The results show that: (1) sampling sites in the mainstream are classified into two groups, upstream and downstream, with downstream representing higher levels of heavy metals and degrees of pollution; (2) three clusters were identified for the 10 tributaries, the downstream having the highest levels of heavy metals’ pollution; (3) the PCA suggests there are significant correlations among Zn, Cu, and Pb between Cr in the basin. Sediment pollution assessment was carried out using Pollution Index (PI) and Geo-Accumulation Index (Igeo). Mercury was the metal with the highest contamination level, followed by Cd and Cr. The results provide an overview of the current status of sediment contamination with measured data and support future policy development for the protection of water quality in the Luan River Basin.  相似文献   

16.
为了解华南地区典型燃煤电厂周边表层土壤重金属空间分布特征,对韶关市燃煤电厂周边20处农田表层土壤中7种重金属(镍(Ni)、铜(Cu)、锌(Zn)、镉(Cd)、铅(Pb)、铬(Cr)及砷(As))的总量进行检测,并分析了其相应的空间分布规律,同时评估了周边土壤重金属的生态风险并分析其来源。结果表明:该燃煤电厂周边土壤中重金属Ni、Cu、Zn、Cd、Pb、Cr及As的平均含量分别是17.79、19.59、159.08、3.14、111.01、96.61 mg/kg和21.48 mg/kg,Cd、Pb污染情况突出,重金属Zn、Cd、Pb、Cr的分布与盛行风向密切相关。综合污染指数法表明,Cd、Pb及Zn处于重污染状态;潜在生态风险指数法表明,Cd处于严重潜在生态风险状态;地累积指数法表明,Ni、Cu整体处于无污染状态,Cd整体处于高污染状态。多种统计方法表明,Zn、Cd、Pb及Cr受燃煤电厂影响明显,Cu、As的来源不仅受燃煤电厂等工业的影响,还与该地区农业灌溉用水密切相关,Ni的分布最为均匀,受自然因素影响明显。  相似文献   

17.
黄河口盐地碱蓬湿地土壤-植物系统重金属污染评价   总被引:6,自引:0,他引:6  
王耀平  白军红  肖蓉  高海峰  黄来斌  黄辰 《生态学报》2013,33(10):3083-3091
以黄河口盐地碱蓬湿地为例,评价了淹水和非淹水区湿地表层土壤As、Cd、Cu、Cr、Pb和Zn 6种重金属的污染程度及其在土壤-植物系统中的迁移、富集特征,分析了不同积水深度和土壤理化性质对研究区土壤重金属含量的影响.研究结果表明,与土壤或沉积物质量标准相比,黄河口盐地碱蓬湿地土壤受As和Cd污染最严重,而其它重金属污染较轻;非淹水土壤Cd、Cr和Zn含量高于淹水湿地,而As、Cu和Pb则较低;而且淹水土壤As含量随积水深度增加而呈下降趋势,但积水深度对其他重金属含量的影响不明显.相关性分析结果表明,按照受土壤关键影响因子的不同重金属(除As外)可以分为两类:第一类为Cd、Cr和Zn,这些重金属含量受土壤pH值和盐分影响较大,且相互间存在显著正相关关系,表明它们可能有相同的来源;第二类为Pb和Cu,它们受土壤pH值、盐分和有机质的影响,且Pb和Cu之间存在显著正相关关系.除Cr、Cu和Zn外,重金属在盐地碱蓬的根系内一般不发生显著富集,但绝大多数重金属都表现出地上部分的含量比根系更高的现象.  相似文献   

18.
Abstract

The distribution, contamination status, and ecological risks of heavy metals in Tahaddart estuary were investigated. 24 surface sediment samples and two cores were collected and analyzed for major (Al and Fe), heavy metals (As, Cd, Cr, Cu, Ni, Pb, and Zn), and grain size composition. The heavy metals assessment was carried out using different environmental indices. The results indicated that the spatial distribution patterns of Al, Fe, and Zn were mainly determined by the distribution of the finer grained fraction (<63?μm) in the sediment. In contrast, As, Cd, Cr, Cu, Ni, and Pb concentrations were controlled by anthropogenic activities (vehicular traffic from Highway Bridge and thermal power plant). The distribution of heavy metals in sediment cores showed an upward enrichment in heavy metals with high concentration found in the uppermost may related to the increasing in human activities. The pollution indexes confirmed that the Tahaddart estuary sediment was considerably to high contaminated by heavy metals near to different anthropogenic inputs. Similarly, the potential ecological risk index and the biological risk index present 21% probability of toxicity posing potential risk to the aquatic organisms. These results provide basic information that can be used to protect and improve the quality of this ecosystem.  相似文献   

19.
城市住宅区是人类活动的重要场所,与居民的日常生活紧密相关。为了解沈阳市住宅区小区与街道灰尘中重金属污染的空间分布,采集了不同住宅区小区与街道的灰尘样品,分析了灰尘中重金属的含量,并使用富集因子和地累积指数评估了其污染程度。结果表明,沈阳市灰尘中重金属Cr、Cd、Cu、Pb和Zn的平均含量均超过辽宁省表层土壤元素背景值。单因素方差分析表明,街道灰尘中重金属Cu、Fe、Mn和Zn的空间分布具有显著性差异,而小区灰尘中重金属Cd、Cr、Fe、Mn和Pb在空间上具有显著性差异。重金属Cd、Zn和Pb的平均污染水平较高,其中小区内Cd和Zn的污染程度高于街道。沈阳市不同方位住宅区灰尘中重金属的污染水平介于轻度污染至中度污染之间。  相似文献   

20.
Xijiang River is the main surface water source in Guangxi province, South China. This study was carried out to investigate the distribution and potential ecological risks of seven heavy metals (Cu, Pb, Zn, As, Cd, Ni, and Cr) in surface sediments in Xijiang River basin. The results illustrated that the average concentrations of Zn, Pb, Cd, Cu, As, Ni, and Cr were 483.9, 207.5, 13.35, 23.50, 312.1, 28.75, and 50.62 mg/kg, respectively. Among them, Zn, Pb, Cd, and As were the major heave metals with concentration exceeding Class 3 threshold value of Chinese national standard. The result also showed samples with high ecological risk were mainly located in the upstream of Xijiang River basin as Diaojiang River, Hongshui River, Jincheng River, and Dahuan River. Based on the pollution risk assessment, the area manifested composite pollution of heavy metals in the sediments, signifying As, Pb, and Cd as the dominant heavy metals, and there were high ecological risk in sediments for these metals. According to correlation matrix and factor analysis (FA), the seven heavy metals were divided into three types/classes, Cd, as and Zn attributed by anthropogenic sources, natural sources corresponds for Ni and Cr while both natural and anthropogenic sources were attributed to Cu.  相似文献   

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