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1.
Airborne particulate matter (APM) is a major air pollutant, and the effect on human health of fine APM (PM2.5) deposited deep inside the lungs has recently become a serious concern. Moreover, soluble constituents may leach from APM, and intensify some health disorders. To identify the soluble chemical constituents of APM, size-classified APM was sampled in central Tokyo, and the elemental compositions of the water-soluble, acid-soluble and insoluble fractions were investigated. The extraction procedure was validated by calculating the mass balance of soluble and insoluble fractions of a standard APM reference material (NIST SRM 1648). Among the major elements, Fe and Ti in APM of all size classes and K in coarse APM were distributed primarily in the insoluble fraction and were inferred to be present as oxides or silicates, whereas Na and Mg in all size classes and K in fine APM were primarily in the water-soluble fraction and were inferred to be have originated mainly from sea salt. Among the trace elements, Zn and Cd in the fine APM (d < 2 microm) had large enrichment factors, indicating an anthropogenic origin, and were distributed primarily in the water-soluble fraction. When fine anthropogenic APM enters into the lungs, leached toxic elements, such as Cd, may adversely affect health. The higher the bonding energy of the monoxide molecule of the element was, the higher its distribution ratio was in the water-soluble fraction. Therefore, many metallic elements in APM were inferred to be present as oxygen-bonded compounds.  相似文献   

2.
Concentrations of 14 rare earth elements (REEs) in six size classes of airborne particulate matter (APM) (<0.43, 0.43-0.65, 0.65-1.1, 1.1-2.1, 2.1-11, and >11 μm) and in two different phases (suspended particulate and dissolved) in rainwater were determined by inductively coupled plasma mass spectrometry (ICP-MS). Positive Eu and Tb anomalies were observed in size-classified APM. These anomalies may be due to large emissions of Eu and Tb to the atmosphere resulting from the recent change in Japan from the use of cathode-ray tubes to plasma displays in television sets (Eu and Tb) and from the widespread use of magneto-optical disks (Tb). The light REEs were enriched in fine APM particles (diameter < 1.1 μm). Because compositions of La/Ce/Sm in fine APM (diameter < 1.1 μm) were similar to those in automobile catalyst, the light REE enrichment was attributed to automobile emissions. In contrast, the REE distribution pattern in the suspended particulate phase in rainwater was similar to that in coarse APM (diameter > 2.1 μm), and a positive Tb anomaly was observed, suggesting that coarse particles easily become trapped in rain droplets. A negative Eu anomaly was observed in the dissolved phase in rainwater, but not in APM or in the suspended particulate phase in rainwater. Unlike other REEs, Eu can exist as both bivalent and trivalent ions in nature, and Eu-selective dissolution from or adsorption onto the trapped particles of Eu might account for the negative anomaly. These results show that atmospheric REE cycling is affected by the physico-chemical properties of APM.  相似文献   

3.
This study aimed at assessing atmospheric deposition of heavy metals and other elements using the moss genera Brachythecium sp. (B. rutabulum and B. salebrosum) and Eurhynchium sp. (E. hians and E. striatum) collected in autumn 2004 in the urban area of Belgrade. The concentrations of 36 elements (Na, Mg, Al, Cl, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Zn, As, Se, Br, Rb, Sr, Mo, Sb, I, Cs, Ba, La, Ce, Sm, Tb, Dy, Hf, Ta, W, Hg, Th, U) were determined in moss and local topsoil samples by instrumental neutron activation analysis. The concentration of elements in moss positively correlated to those obtained for topsoil. High enrichment factors for As, Zn, Mo, Br, Sb, Se, Hg and Cl, calculated to continental crust composition, gave an evidence for anthropogenic impact on urban area, mainly due to intensive vehicular traffic and fossil fuel combustion. The concentration of elements in moss, characteristic for fossil fuel combustion, obtained in this study were substantially lower than in the previous investigation (2000) conducted in the area of Belgrade. The level of concentrations for V, Cr, Ni, and As in moss from this study correlated to those measured for neighboring countries, and were several times higher than the base-level data from low polluted areas. The level of accumulated elements in both investigated moss genera were similar and all studied species could be combined for biomonitoring purposes in urban areas.  相似文献   

4.
The volcano Copahue, Neuquén province, Argentina has shown infrequent explosive eruptions since the 18th century. Recently, eruptive activity and seismicity were registered in the period July-October, 2000. As a consequence, ash clouds were dispersed by winds and affected Caviahue village located at about 9 km east of the volcano. Samples of deposited particles from this area were collected during this episode for their chemical analysis to determine elements of concern with respect to the health of the local population and its environment. Different techniques were used to evaluate the distribution of elements in four particle size ranges from 36 to 300 microm. X-ray powder diffraction (XRD) was selected to detect major components namely, minerals, silicate glass, fragments of rocks and sulfurs. Major and minor elements (Al, Ca, Cl, Fe, K, Mg, Mn, Na, S, Si and Ti), were detected by energy dispersive X ray analysis (EDAX). Trace element (As, Cd, Cr, Cu, Hg, Ni, Pb, Sb, U, V and Zn) content was quantified by inductively coupled plasma-mass spectrometry (ICP-MS). Nuclear activation analysis (NAA) was employed for the determination of Ce, Co, Cs, Eu, Hf, La, Lu, Rb, Sc, Sm, Ta and Yb. An enrichment was observed in the smallest size fraction of volcanic ashes for four elements (As, Cd, Cu and Sb) of particular interest from the environmental and human health point of view.  相似文献   

5.
重庆城区不同粒径颗粒物元素组分研究及来源识别   总被引:2,自引:2,他引:0  
为研究重庆市大气颗粒物的污染特征及其来源,于2010年3—10月在主城区分别采集PM1.0、PM2.5和PM103种粒径的颗粒物样品,利用XRF分析其中的26种元素浓度。结果表明,重庆市主城区S元素在各粒径中含量都较高,细粒子中K的含量较高,粗粒子中Si、Ca和Fe的浓度较大。富集因子分析表明,主城区Cd、S、Se等污染元素的富集系数较大,且粒径越小,富集现象越明显。利用因子分析得出土壤风沙、扬尘、燃煤的燃烧、机动车燃油产生的尾气排放、生物质燃烧排放是重庆市颗粒物污染的主要来源。  相似文献   

6.
Air particulate samples collected during 1995–96 ata background site situated on the east coast of Thar Desert inRajsthan State of India were analysed for atmospheric dustloads (Suspended Particulate Matter) and elemental composition.The values of SPM ranged from 9 g M-3 to 97g M-3 with an average of 43 g M-3 except a fewepisodic values, which were 3 to 5 times higher than the averageduring summer months. The results for elemental composition ofthe particulate samples showed that the concentrations ofanthropogenic toxic trace elements viz. Br, Cr, Pb, Sb, Se and Znare lower by a factor of 2 to 10 as compared to urban areas. Thehigh enrichment factors for anthropogenic elements viz. Br, Pb,Sb and Zn show an input from coal/wood fuel burning andvehicular pollution at the sampling site. The depletion of Si inSPM samples shows long distance transport of dust to the samplingsite.  相似文献   

7.
Soils play a vital role in the quality of the urban environment and the health of its residents. City soils and street dusts accumulate various contaminants and particularly potentially toxic elements (PTEs) from a variety of human activities. This study investigates the current condition of elemental concentration in the urban soils of Hamedan, the largest and the fastest-growing city in western Iran. Thirty-four composite soil samples were collected from 0 to 10 cm topsoil of various land uses in Hamedan city and were analyzed for total concentration of 63 elements by ICP-MS. The possible sources of elemental loadings were verified using multivariate statistical methods (principal component analysis and cluster analysis) and geochemical indices. The spatial variability of the main PTEs was mapped using geographic information system (GIS) technique. The results revealed a concentration for As, Co, Cr, Mn, Mo, Ni, and V in the soil samples comparable to the background values as well as a range of associations among these elements in a single component suggesting geogenic sources related to geological and pedogenic processes, while the soils mostly presented a moderate to considerable enrichment/contamination of Cd, Zn, Pb, and Sb and moderate enrichment/contamination of Cu, Zn, and Mo. It was found that anthropogenic factors, vehicular traffic in particular, control the concentration of a spectrum of elements that are typical of human activities, i.e., Cd, Cu, Hg, Pb, Sb, and Zn. Lead and Sb were both the most enriched elements in soils with no correlation with land use highlighting general urban emissions over time and the impact of transport networks directly on soil quality. The highest concentrations of As were recorded in the southern part of the city reflecting the influence of metamorphic rocks. The effect of the geological substrate on the Co and Ni contents was confirmed by their maximum concentrations in the city’s marginal areas. However, high spatial variability of urban elements’ contents displayed the contribution of various human activities. In particular, the increased concentration of Cd, Sb, and Pb was found to be consistent with the areas where vehicular traffic is heaviest.  相似文献   

8.
An aerosol time-of-flight mass spectrometer (ATOFMS) was used to determine, in real time, the size and chemical composition of individual particles in the atmosphere at the remote inland site of Eskdalemuir, Scotland. A total of 51,980 particles, in the size range 0.3-7.4 microm, were detected between the 25th and 30th June 2001. Rapid changes in the number density, size and chemical composition of the atmospheric aerosol were observed. These changes are attributed to two distinct types of air mass; a polluted air mass that had passed over the British mainland before reaching Eskdalemuir, interposed between two cleaner air masses that had arrived directly from the sea. Such changes in the background aerosol could clearly be very important to studies of urban aerosols and attempts at source apportionment. The results of an objective method of data analysis are presented. Correlations were sought between the occurrence of: lithium, potassium, rubidium, caesium, beryllium, strontium, barium, ammonium, amines, nitrate, nitrite, boron, mercury, sulfate, phosphate, fluorine, chlorine, bromine, iodine and carbon (both elemental and organic hydrocarbon) in both fine (d < 2.5 microm) and coarse (d > 2.5 microm) particle fractions. Several previously unreported correlations were observed, for instance between the elements lithium, beryllium and boron. The results suggest that about 2 in 3 of all fine particles (by number rather than by mass), and 1 in 2 of all coarse particles containing carbon, consisted of elemental carbon rather than organic hydrocarbon (although a bias in the sensitivity of the ATOFMS could have affected these numbers). The ratio of the number of coarse particles containing nitrate anions to the number of particles containing chloride anions exceeded unity when the air mass had travelled over the British mainland. The analysis also illustrates that an air mass of marine origin that had travelled slowly over agricultural land can accumulate amines and ammonium.  相似文献   

9.
The biomonitors Hypnum cupressiforme and Xanthoria parietina were used to assess the deposition of trace elements and their possible origin in the Prades Mountains, a protected Mediterranean forest area of NE Spain with several pollution sources nearby. Al, As, Cd, Co, Cu, Cr, Ni, Pb, Sb, Ti, V, and Zn were determined in 16 locations within this protected area. Soil trace element concentrations were also ascertained to calculate enrichment factors (EF) and use them to distinguish airborne from soilborne trace element inputs. In addition, lichen richness was measured to further assess atmospheric pollution. EF demonstrated to be useful not only for the moss but also for the lichen. Cd, Cr, Cu, Ni, and Zn presented values higher than three in both biomonitors. These trace elements were also the main ones emitted by the potential sources of pollutants. The distance between sampling locations and potential pollution sources was correlated with the concentrations of Cu, Sb, and Zn in the moss and with Cr, Ni, and Sb in the lichen. Lichen richness was negatively correlated with lichen Cu, Pb, and V concentrations on dry weight basis. The study reflected the remarkable influence that the pollution sources have on the presence of trace elements and on lichen species community composition in this natural area. The study highlights the value of combining the use of biomonitors, enrichment factors, and lichen diversity for pollution assessment to reach a better overview of both trace elements’ impact and the localization of their sources.  相似文献   

10.
鞍山市大气尘和金属元素沉降通量及污染特征   总被引:5,自引:3,他引:2  
通过采集鞍山市11个点位的降尘样品以及土壤样品,用ICP-MS分析了Cu、Mn、Zn、Pb等元素含量,并计算其沉降通量。结果表明,鞍山地区大气降尘的沉降通量为2.92~59.8g/(m2.month),其中鞍钢厂区沉降通量均值为31.6g/(m2.month),分别是周边地区和对照地区的4.72倍和10.5倍。重金属As、Cr、Pb和Cd的沉降通量分别为3.78、45.5、42.8、0.457g/(hm2.month)。降尘中各元素的富集系数为0.29~190,其中Cu、Fe、Zn、Mo、Cd、Pb和Se的富集系数大于10,说明这些元素主要来自于人为源。鞍钢厂区土壤中Cu、Pb、Mn、Zn、Mo、Cd、Ca、Fe和Se的含量较辽宁省土壤背景值高,说明其土壤环境已经受到了人类活动的影响。  相似文献   

11.
Investigations of the existing chemical forms and the concentrations of arsenic (As), selenium (Se) and antimony (Sb) in samples of fly ash obtained from six coal-fired power stations in various countries were carried out. The concentration of As was found to vary from 5.4 to 22.3 mg kg(-1), and the most common mode of occurrence of As in the fly ashes is in association with carbonates or Fe-Mn oxides. The concentrations of Se and Sb ranged from 2.3-5.2 and 1.0-3.9 mg kg(-1), respectively. The dominant chemical forms of Se and Sb in the fly ashes were as extractable species. Also, water-soluble As, Se and Sb in the fly ashes were extracted, and the chemical species of As, Se and Sb in the extract determined using HPLC-ICP-MS. This was done as the potential release of soluble As, Se and Sb through leaching of fly ash is of environmental concern. The most abundant form of As in the extract was the low toxicity As(V). The main species of Se was Se(IV), although it was found that the ratio of Se(VI) to Se(IV) in acidic fly ashes is higher than in alkaline fly ash samples. Antimony was mostly present as Sb(III).  相似文献   

12.
An active biomonitoring of the heavy metals pollution experiment was undertaken by means of the bryophyte species Scleropodium purum transplanted at three different sites exposed to rural, traffic, or industrial influences. Concentrations of about 40 elements in S. purum were determined by instrumental neutron activation analysis and inductively coupled plasma mass spectrometry. Accumulation rates of heavy metals were determined in the three sites. These accumulation rates in polluted sites were matched together and also to those recorded at the rural site. The changes of the accumulation rate of heavy metals in S. purum versus their concentrations in PM10 particles simultaneously collected above show some different accumulation properties of S. purum according to elements and sites. S. purum has a weak efficiency in the three sites to accumulate elements like V, Cr, Cu, Zn, As, Se, Sb, and Pb originating from atmospheric hot sources generally enriched in particulates matter (PM10), whereas it is particularly high for Br, Th, and Rb. For other elements, Co, La, Ce, and Hf, and rare earth elements, Fe, Sr, Nb, Ti, Al, and Sc, the collection efficiency by S. purum is intermediate. In the industrial site Dunkerque, a magnification of the collection efficiency by S. purum for elements originating from steel and aluminum productions and petroleum refinement suggests that these metals could be enriched in coarse particles with a better accumulation by the bryophyte with respect to PM10.  相似文献   

13.
Tree barks and attic dusts were examined as historical archives of smelter emissions, with the aim of elucidating the pathways of pollution associated with a plume of Sn and Pb contamination in top soils, found close to the former Capper Pass smelter, Humberside, UK. Samples were collected from three villages within the area of the contamination plume. Scanning electron microscopy (SEM) and bulk chemical analyses were used to assess particle type, number and deposition patterns. SEM analysis of dusts and bark revealed that Sn and Pb particles were present in samples from all three villages along with copper, zinc and iron particles. These were almost entirely <10 microm in diameter and occurred mostly as oxides, frequently forming clusters of sub-micron crystals. Samples further from the smelter contained considerably fewer particles. We present images of smelter derived Sn particles. Chemical assays of the barks and attic dusts demonstrated that concentrations of Sn, Pb, Cu, As, Sb and Cd diminished with increasing distance from the source. Strong positive correlations were found between Sn and Pb, As, Sb and Cd in the attic dusts. Enrichment factors (EF) were calculated for these trace elements based on topsoil element concentrations obtained from the soil survey of the study area. Decreases in these trace element concentrations and EF values with distance away from the smelter are consistent with trends found in the soil survey for Sn and Pb and are typical of deposition patterns around smelter stacks. The study demonstrates that tree bark and attic dusts can be effective archives of metal particulates deposited from large static emission sources.  相似文献   

14.
干旱区中小城市降雪中金属元素沉降通量研究   总被引:1,自引:0,他引:1  
文章以干旱区中小城市昌吉市为研究区,选择2011年12月至2012年2月期间较为典型的6场次降雪进行采样,利用ICP-MS测定降雪中20种金属元素,并探讨金属元素的沉降通量、富集特征及其来源。研究表明,降雪中Al的年沉降通量最大,为10.32 mg/m2;Fe、Ba、Zn、V、Cu的年沉降通量次之,集中在1.40~6.11 mg/m2;As、Ni、Mn、Cr、Mo、Sb年沉降通量较小,集中在0.08~0.39 mg/m2;Be、Co、Cd、Pb、Hg、Tl、Th、U的年沉降通量最小,集中在0.001~0.053 mg/m2。Al、Fe、Mn、Be、Th富集系数在0.32~3.05之间,这些金属元素主要来自自然来源;Cd与Hg富集系数分别为923.23、2511.47,达到严重富集的程度;其余金属元素富集系数在10~500之间,属中度富集。昌吉州境内煤炭资源丰富,近年煤炭开采量较大,城区供暖面积不断加大,供暖不断加强;市区车流量急剧增加,运输排放加剧;近郊及周边地区各类工业的分布等是各类金属元素在雪中富集的主要原因。冰雪节后冰灯拆除,降雪可有效捕集大气中的汞,冬季气温不利于Hg挥发等对Hg的严重富集也有重要影响。  相似文献   

15.
Kidney and muscle samples were collected from 197 bovine and 33 porcine carcasses and liver and muscle from 115 poultry carcasses across the province. These tissues were analyzed for the following 13 elements, Ag, As, Cd, Co, Cr, Cu, Hg, Mo, Ni, Pb, Sb, Se, and Zn. The intent of the study was to determine normal background levels. Tissue concentration of these elements fell into five orders of magnitude ranging from < 10 g kg–1 for Ag to over 10 mg kg–1 for Zn. Similar concentrations were observed in the three specie tissues being compared except for higher concentrations of Cd and Sb in bovine kidneys. In avian tissues Mo contents were higher in liver than muscle. When samples from all three species were grouped by age, no distinct trends were observed to indicate an increase in metal contents with age, with the exception of Cd in bovine kidneys.  相似文献   

16.
The study was undertaken to examine the nature of particulate chalk dust settled on classroom floor during traditional teaching with dusting and non-dusting chalks on two types of boards viz. rough and smooth. Settling chalk particles were collected for 30 min during teaching in glass Petri plates placed in classrooms within 3 m distance from the teaching boards. Particle size distribution, scanning electron microscopic images of chalk dusts and compressive strength of two types of chalks were tested and evaluated. Results showed that a larger proportion of dusts generated from anti-dusting chalks were of <4.5 and <2.5 microm size on both smooth and rough boards, as compared to dusting chalks. Non-dusting chalks, on an average, produced about 56% and 62% (by volume) of <4.5 microm (respirable) diameter, on rough and smooth boards, respectively, while the corresponding values for dusting chalks were 36% and 45%. Also, on an average, 83% and 94% (by volume) of the particles were <11 microm (thoracic) in case of non-dusting chalks against 61% and 72% for dusting chalks on rough and smooth boards, respectively. Interestingly, taking into account the mass of chalk dust produced per unit time, which was higher in dusting chalks than non dusting chalks, the former was actually producing higher amount of PM <4.5 and <11 particles from both types of boards. Scanning electron microscope images revealed that chalk particles had random shape, although in dusting chalks prevalence of elongated particles was observed, apparently due to the longitudinal breaking of the chalks during writing, which was confirmed during compressive strength testing. We could conclude that dusting chalks could be potentially more harmful than anti dusting chalks, as they produced higher amount of potentially dangerous PM 4.5 and PM 11.  相似文献   

17.
Airborne particulate matter, suspected to induce adverse effects on human health, have been one of the most important concerns regarding recent air pollution issues in Japan. To characterize regional and seasonal variations in emission sources of fine airborne particulate matter (d < 2 microm), monthly samples (n = 36 for each site) were collected at urban (Tokyo), suburban (Maebashi), and mountainous (Akagi) sites in Japan from April 2003 to March 2006. Multielement analysis of chemical species (Na, Al, K, Ca, V, Cr, Mn, Fe, Ni, Cu, Zn, As, Sb, and Pb) was performed by inductively coupled plasma-atomic emission spectrometry and inductively coupled plasma-mass spectrometry. The combined source receptor model, which consists of positive matrix factorization and chemical mass balance, determined the contributions of nine emission sources (local and continental soils, road dust, coal and oil combustion, waste incineration, steel industry, brake wear, and diesel exhaust) to the observed elemental concentrations. Large regional differences were identified in the source contributions among the observational sites. Diesel exhaust was identified as the most significant source (70% of identified contributions) at the urban site. Local and continental soils, coal combustion, and diesel exhaust were intricately assigned (20-30% each) to the suburban site. Continental soil was the predominant source (65%) at the mountainous site. Respective significant source contributions dominated the seasonal variations of total elemental concentrations at each site. These results suggest that a better understanding of the regional and seasonal characteristics of impacting emission sources will be important for improving regional environments.  相似文献   

18.
Looking for robust indicators of motor vehicle emissions it has been found that brake wear and linings are significant contributors of Cu, Mo and Sb to air particulate matter. These trace elements, whose mutual ratios in airborne particulate matter resulted quite different from those in crustal material, appear to be available fingerprinting tools to identify the contribution of on-road vehicles to traffic-derived particulate matter. In this study, the results of analytical determinations of Cu, Mo and Sb on PM(10), PM(2.5), vegetation and brake dust samples, together with gas (CO, NOx) concentrations, are discussed. Highly significant correlations among Cu, Sb and Mo were observed in particulate matter from Palermo and between Cu-Sb and Cu-Mo at Catania. Further significant positive correlations have been found in pine needles from Palermo, Gela and in platanus leaves from Catania.  相似文献   

19.
Two cores collected in 2001 and 2004 from Flanders Moss ombrotrophic peat bog in central Scotland were dated (14C, 210Pb) and analysed (ICP-OES, ICP-MS) to derive and compare the historical atmospheric deposition records of Sb and Pb over the past 2500 years. After correction, via Sc, for contributions from soil dust, depositional fluxes of Sb and Pb peaked from ca. 1920-1960 A.D., with >95% of the anthropogenic inventories deposited post-1800 A.D. Over the past two centuries, trends in Sb and Pb deposition have been broadly similar, with fluctuations in the anthropogenic Sb/Pb ratio reflecting temporal variations in the relative input from emission sources such as the mining and smelting of Pb ores (in which Sb is commonly present, as at Leadhills/Wanlockhead in southern Scotland), combustion of coal (for which the Sb/Pb ratio is approximately an order of magnitude greater than in Pb ores) and exhaust emissions (Pb from leaded petrol) and abrasion products from the brake linings (Sb from heat-resistant Sb compounds) of automobiles. The influence of leaded petrol has been most noticeable in recent decades, firstly through the resultant minima in Sb/Pb and 206Pb/207Pb ratios (the latter arising from the use of less radiogenic Australian Pb in alkylPb additives) and then, during its phasing out and the adoption of unleaded petrol, complete by 2000 A.D., the subsequent increase in both Sb/Pb and 206Pb/207Pb ratios. The extent of the 20th century maximum anthropogenic enrichment of Sb and Pb, relative to the natural Sc-normalised levels of the Upper Continental Crust, was similar at approximately 50- to 100-fold. Prior to 1800 A.D., the influence of metallurgical activities on Sb and Pb concentrations in the peat cores during both the Mediaeval and Roman/pre-Roman periods was discernible, small Sb and Pb peaks during the latter appearing attributable, on the basis of Pb isotopic composition, to the mining/smelting of Pb ores indigenous to Britain.  相似文献   

20.
Forty-two soil and apple samples from central Greece were collected and analyzed with regards to the content in major (Ca, Fe, K, Mg, Na, P, and S) and trace elements (As, B, Ba, Cd, Co, Cr, Cu, Hg, Mn, Mo, Ni, Pb, Sb, Sc, Se, Sr, Ti, and Zn). Soil samples were analyzed by inductively coupled plasma atomic emission spectrometry, while for the apples inductively coupled plasma mass spectrometry was implemented. Several elements such as As, B, Cd, Cr, Cu, Fe, Mn, Ni, Pb, Se, Ti, and Zn, represent high concentrations in apples from the study area. These relatively high concentrations may be a consequence of the local geology, along with the excessive application of agricultural products such as fertilizers and agrochemicals.  相似文献   

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