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1.
以太原市2013年冬季大气细颗粒物(PM2.5)为研究对象,定性与定量分析了其中多环芳烃(PAHs)、硝基多环芳烃(NPAHs)、硫酸盐(SO2-4)和硝酸盐(NO-3)的浓度及其昼夜变化。采用特征比值法分析了PAHs、SO2-4和NO-3的来源,并通过PEFs毒性评价法评价了PM2.5中PAHs的BaP等效毒性,估算出个体致癌指数。结果显示,太原市PM2.5中16种PAHs总含量、3种NPAHs总含量及SO2-4和NO-3含量分别在102~153 ng/m3、0.41~0.48 ng/m3、4.89~5.87μg/m3和1.69~1.71μg/m3范围内,且其夜间浓度均高于白天。PAHs的BaP等效毒性和个体致癌指数超过标准值。结果提示,太原市PM2.5中PAHs、NPAHs、SO2-4和NO-3污染主要是由于燃料燃烧和固定源引起的,且颗粒物上的PAHs浓度高,对人体健康有潜在的风险。  相似文献   

2.
《Planning》2019,(2)
目的了解兰州市城关区大气细颗粒物(PM_(2.5))中多环芳烃(PAHs)的季节污染特征,并对其健康风险进行评价。方法选择兰州市城关区作为采样点,于2015年1月—2015年12月期间周期性采集大气PM_(2.5)样品84份,利用高效液相色谱仪分析其中PAHs的含量。结果 2015年总PHAs浓度变化范围为(3.64~268.23) ng/m~3,季节变化规律为冬季>秋季>春季>夏季。在不同季节,3-5环PAHs占总PAHs的比例最大。通过健康风险评估发现,成人通过呼吸道途径暴露造成的终生致癌超额危险额度均已超过人群可接受最大风险水平,儿童终生致癌超额危险度处于可接受水平。结论兰州市城关区大气PM_(2.5)中PAHs污染水平较高,人们长期暴露在此环境中,存在一定致癌风险。  相似文献   

3.
人工介质去除源水中多氯联苯和多环芳烃研究   总被引:2,自引:1,他引:1  
考察了人工介质富集微生物对W市源水中多氯联苯(PCBs)和多环芳烃(PAHs)的去除效果。试验结果表明,源水中存在较高浓度的PAHs;当介质的填充密度(介质与水的体积比)从15.6%增加到38%时,对PCBs和PAHs的去除率均有所增加;当HRT从3d增加到7d时,对PCBs和PAHs的去除率均没有明显提高。可见增加介质填充量有利于对PCBs和PAHs的去除,通过人工介质富集微生物对源水中的PCBs和PAHs有一定的去除效果,但出水PAHs浓度难以达到《城市供水水质标准》(CJ/T206-2005)的要求。  相似文献   

4.
《Planning》2019,(2)
目的了解北京市春季大气颗粒物中多环芳烃分布现状及来源特征。方法记录北京市环境保护监测中心公布的空气质量信息,采用大气颗粒物采样仪在北京市某区进行采样。索式提取法提取细颗粒物(PM_(2.5))中的有机物,用气相色谱—质谱联用仪定量分析PAHs,分子诊断比值法分析多环芳烃的来源。结果环境空气质量指数(AQI)日均值与蒽、荧蒽、苯并[a]蒽、■、苯并[b]荧蒽、茚并(1,2,3-cd)芘呈现正相关,与苊、芴呈负相关,其中与苯并[b]荧蒽的相关系数最高(r=0.772)。随着空气质量由优到严重污染发展,苯并[a]芘、茚并[1,2,3-cd]芘、苯并[ghi]苝三种多环芳烃质量浓度有上升的趋势且差异具有统计学意义(P<0.01);苊、芴、菲、芘四种多环芳烃质量浓度有下降的趋势且差异具有统计学意义(P<0.01);特征来源分析发现,空气质量为优和良的情况下细颗粒物中PAHs主要来源于石油和液态化石燃料的燃烧;空气质量为重度和严重污染的情况下,PAHs来源除了液态化石燃料燃烧外还有木材和煤炭燃烧。结论 2014年北京市某区春季的大气细颗粒物中的多环芳烃主要来源于煤和化石燃料的燃烧,可能与居民取暖和交通污染有关。  相似文献   

5.
《Planning》2017,(5)
目的了解兰州市城区大气细颗粒物(PM_(2.5))中多环芳烃(PAHs)的污染水平及分布特征。方法选择兰州市西固区和城关区作为采样点,于2015年1月—2016年12月期间周期性采集大气PM_(2.5)样品342份,利用高效液相色谱仪测定分析其中PAHs含量。结果 PM_(2.5)日平均质量浓度采暖期高于非采暖期,差异具有统计学意义(P<0.01)。总PAHs质量浓度2015年高于2016年;城关区高于西固区;采暖期高于非采暖期,差异均具有统计学意义(P<0.05)。检出的15种PAHs单体中,苯并[a]芘(Bap)日平均质量浓度约为世界卫生组织规定限值(1.0 ng/m~3)的90倍。结论兰州市城区大气PM_(2.5)中PAHs污染水平较高,PAHs的分布具有时空性。  相似文献   

6.
离子色谱法是分析火灾烟气成分的主要分析方法之一。采用离子色谱法对火灾烟气中常见毒性气体相对应的阴离子F^-、Cl^-、NO2^-、SO4^2-、Br^-、NO3^-、PO4^3-等进行了分析研究,给出了离子色谱法在实际火灾中的应用案例。  相似文献   

7.
《Planning》2019,(2)
目的建立一种便捷、高效的方法来检测大气细颗粒物(PM_(2.5))中的16种多环芳烃(PAHs)。方法乙腈—超声水浴萃取样品中的PAHs,经过ENV固相萃取柱净化,多环芳烃专用色谱柱分离,再用液相色谱—荧光—紫外检测器串联进行检测。结果 16种PAHs在线性范围内有良好的线性关系,相关系数均≥0.999 9,检出限范围为(0.04~0.26) ng/m~3,平均回收率为85%~114.1%,相对标准偏差均小于8.0%。结论本方法提取过程简单、灵敏度高、精密度高,适用于PM_(2.5)中PAHs的污染分析。  相似文献   

8.
通过现场试验,考查了多环芳烃(PAHs)从污泥向芦苇的转移以及PAHs在芦苇各部位的分布情况。受试芦苇植于污泥干化芦苇床内,芦苇床规格3 m×1 m×1.3 m,其中高度含0.65 m填料层和0.65 m超高。试验进行了3 a,包括2 a的污泥负荷期和1 a的闲置期。2 a负荷期内共进泥8.4 m(含水率99.14%),污泥PAHs含量平均5.69 mg·kg -1。原生芦苇茎和叶中的PAHs含量相对较高,达到2.198和2.583 mg·kg -1 (DW),分别是芦苇根PAHs含量的2.44和2.87倍,且以低环PAHs为主。运行结果表明,受试芦苇对污泥中的PAHs产生了明显的富集作用。运行第2年9、10和11月取污泥干化芦苇床芦苇样品并进行检测,发现芦苇根茎叶内PAHs含量呈逐月升高趋势;第3年11月芦苇根茎叶所含PAHs总量分别为7.642、7.713、7.946 mg·kg -1 (DW),相对原生芦苇分别提高了8.50、3.52和3.08倍,且以低环PAHs为主,根茎叶低环PAHs含量占PAHs总量的55.14%、56.96%和44.59%。芦苇中PAHs的含量与植物含脂率具有显著的正相关关系,而与芦苇的含水量无关。  相似文献   

9.
利用反硝化抑制硫酸盐还原的连续流试验研究   总被引:2,自引:1,他引:1  
为控制油田地面系统中硫酸盐还原菌产生硫化物造成设备腐蚀.采用连续流ABR反应器进行了反硝化抑制硫酸盐还原的研究,考察了反硝化抑制硫酸盐还原的影响因素和运行效果。结果表明,SO4^2-/NO3^-值和COD含量是影响反硝化抑制硫酸盐还原的最重要因子.SO4^2-/NO3^-值为1:1时抑制效果最佳,较低的COD含量有利于提高抑制效果,利用反硝化抑制硫酸盐还原必须在硝酸盐的有效作用区段内进行。氧化还原电位为-50~-150mV时.反硝化作用占优势地位;氧化还原电位为-300~-400mV时。硫酸盐还原反应占优势地位。  相似文献   

10.
《Planning》2014,(30)
本文对南京市2013年的降水监测数据和空气自动监测数据进行分析,初步得出南京市大气降水对空气质量的影响。非降雨日空气中的SO2、NO2、PM10和PM2.5平均浓度比降雨日的要高,降水对SO2的影响最大,其次是对PM2.5和PM10,对NO2的影响最小。降水较少时,降水对空气中的颗粒物净化作用不大,甚至可能导致颗粒物的吸湿增长,反而使颗粒物浓度升高。南京市PM2.5的主要水溶性离子和降水中的离子成分基本一致,降水对PM2.5中的水溶性离子也有一定的削减作用,其中对SO42-、NO3-、NH4+、Cl-和K+的削减效率尤为明显,其削减比例均在30%~50%之间。  相似文献   

11.
Airborne fine (PM(2.5)) and coarse (PM(2.5-10)) particulate matter was collected from January to December in 2007 in Zonguldak, Turkey using dichotomous Partisol 2025 sampler. Fourteen selected polycyclic aromatic hydrocarbons (PAHs) in particulate matter were determined simultaneously by high-performance liquid chromatography with fluorescence detection (HPLC-FL) and seasonal distributions were examined. The source identification of PAHs in airborne particulates was performed by principal component analysis (PCA) in combination with diagnostic ratios. The predominant PAHs determined in PM(2.5) were pyrene, fluoranthene, benzo[a]anthracene, chrysene, benzo[b]fluoranthene and benzo[a]pyrene. The total concentrations of PAHs were up to 464.0 ng m(-3) in fine and 28.0 ng m(-3) in coarse fraction in winter, whereas in summer times were up to 22.9 and 3.0 ng m(-3) respectively. Approximately 93.3% of total PAHs concentration was determined in PM(2.5) in winter and 84.0% in summer. The concentration levels of PAHs fluctuate significantly within a year with higher means and peak concentrations in the winter compared to that of summer times. Higher benzo(a)pyrene-equivalent (BaPE) concentrations of PAHs were obtained for PM(2.5) especially in winter. The results obtained from PCA in combination with diagnostic ratios revealed that coal combustion and vehicle emissions were the major pollutant sources for both PM(2.5) and PM(2.5-10) associated PAHs in studied area. Two principal components for PM(2.5) and three for PM(2.5-10) were identified and these accounted for 89.4 and 85.2% of the total variance respectively. The emissions from coal combustion were estimated to be the main source of PAHs in the ambient air particulates with contributions of 80.8% of total variance for PM(2.5) and 53.8% for PM(2.5-10).  相似文献   

12.
Sub-Saharan Africa has the highest rate of urban population growth in the world, with a large number of urban residents living in low-income "slum" neighborhoods. We conducted a study for an initial assessment of the levels and spatial and/or temporal patterns of multiple pollutants in the ambient air in two low-income neighborhoods in Accra, Ghana. Over a 3-week period we measured (i) 24-hour integrated PM(10) and PM(2.5) mass at four roof-top fixed sites, also used for particle speciation; (ii) continuous PM(10) and PM(2.5) at one fixed site; and (iii) 96-hour integrated concentration of sulfur dioxide (SO(2)) and nitrogen dioxide (NO(2)) at 30 fixed sites. We also conducted seven consecutive days of mobile monitoring of PM(10) and PM(2.5) mass and submicron particle count. PM(10) ranged from 57.9 to 93.6 microg/m(3) at the four sites, with a weighted average of 71.8 microg/m(3) and PM(2.5) from 22.3 to 40.2 microg/m(3), with an average of 27.4 microg/m(3). PM(2.5)/PM(10) ratio at the four fixed sites ranged from 0.33 to 0.43. Elemental carbon (EC) was 10-11% of PM(2.5) mass at all four measurement sites; organic matter (OM) formed slightly less than 50% of PM(2.5) mass. Cl, K, and S had the largest elemental contributions to PM(2.5) mass, and Cl, Si, Ca, Fe, and Al to coarse particles. SO(2) and NO(2) concentrations were almost universally lower than the US-EPA National Ambient Air Quality Standards (NAAQS), with virtually no variation across sites. There is evidence for the contributions from biomass and traffic sources, and from geological and marine non-combustion sources to particle pollution. The implications of the results for future urban air pollution monitoring and measurement in developing countries are discussed.  相似文献   

13.
Gaseous and particulate matter measurements were performed from January 1999 to December 2001 to assess seasonal and diurnal patterns of air pollutions in the Lanzhou Valley, China. The objectives are the determination of the temporal variability of total suspended particulate (TSP) matter and PM10 levels, and their relationship with the SO2 and NOx emissions and desert dust intrusions from the dust sources in the Hexi Corridor in Gansu Province. The results showed that concentrations of gaseous and particulate pollutants undergo seasonal variations characterized by a winter maximum levels for SO2 (0.094-0.208 mg/m3) and NO2 (0.068-0.089 mg/m3) and a spring maximum levels for TSP (0.885-1.037 mg/m3). Linear regression analysis indicated that the diurnal mean TSP/PM10 ratio may approximate to 3.0, and that the annual NO2/NOx ratio was approximately 0.86, with its highest monthly average of 0.91 in June and its lowest monthly average of 0.788 in January. The origin of PM10 episodes was investigated by correlating the PM10 episodes in the Lanzhou Valley with the high wind speeds in Jinchang (dust sources) in the Hexi Corridor, and also, by comparing the PM10 levels with the SO2 and NOx concentrations. Most of the 'high PM10 episodes' (1-h mean maximum >1.0 mg/m3) were attributed to the desert dust intrusions from the Hexi Corridor. The influence of the industrial and domestic emissions in the PM10 levels was evidenced during most of the periods with the PM10 levels less than 1.0 mg/m3.  相似文献   

14.
In this study, the hourly variations of the mass concentrations of PM10, SO2, NO(x) and O3 at three sampling sites were observed in Beijing during dust storm occurrence period in April 2000. The PM2.5 samples were simultaneously collected. By comparing the hourly variations of the pollutant concentrations before, during and after dust storm event and haze pollution episode, the variation characteristics of the mass concentrations of PM10, SO2, NO(x) and O3 during dust storm events were presented. The results show that the mass concentration of PM10 reached 1500 microg m(-3) during dust storm events on April 6 and 25, 2000, which was 5-10 times that of the non-dust weather conditions, and this period of high mass concentration of PM10 lasted for about 14 h, and then the concentration level prior to the dust event was recovered in 6-h time period. Due to the strong wind, the concentrations of SO2, NO(x), NO2 and O3 during dust storm period were maintained at low levels, which was significantly different from those on non-dust storm and haze pollution conditions. A lot of coarse particles as well as a very large amount of fine particles were contained in the atmospheric particulates during dust storm period, and the concentration level of PM2.5 was comparable to that during haze pollution episode. During the dust storm period, the PM2.5 concentration was approximately 230 microg m(-3), accounting for 30% of the total PM10 mass concentration, was four times that of non-dust weather conditions, and the crustal elements constituted about 66.4% of the chemical composition of PM2.5 while sulfate and nitrate contributed much less, which was quite different from the chemical composition of PM2.5 primarily constituted by sulfate, nitrate and organics on haze pollution day.  相似文献   

15.
An exposure study of children (aged 10-12 years) living in Santiago, Chile, was conducted. Personal, indoor and outdoor fine and inhalable particulate matter (< 2.5 .m in diameter, PM2.5 and < 10 microm in diameter, PM10, respectively), and nitrogen dioxide (NO2) were measured during pilot (N = 8) and main (N = 20) studies, which were conducted during the winters of 1998 and 1999, respectively. For the main study, personal, indoor and outdoor 24-h samples were collected for five consecutive days. Similar mean personal, indoor and outdoor PM2.5 concentrations (69.5, 68.5 and 68.1 microg/m3, respectively) were found. However, for coarse particles (calculated as the difference between measured PM10 and PM2.5, PM2.5-10), indoor and outdoor levels (35.4 and 47.4 microg/m3) were lower than their corresponding personal exposures (76.3 microg/m3). Indoor and outdoor NO2 concentrations were comparable (35.8 and 36.9 ppb) and higher than personal exposures (25.9 ppb). Very low ambient indoor and personal O3 levels were found, which were mostly below the method's limit of detection (LOD). Outdoor particles contributed significantly to indoor concentrations, with effective penetration efficiencies of 0.61 and 0.30 for PM2.5 and PM2.5-10, respectively. Personal exposures were strongly associated with indoor and outdoor concentrations for PM2.5, but weakly associated for PM2.5-10. For NO2, weak associations were obtained for indoor-outdoor and personal-outdoor relationships. This is probably a result of the presence of gas cooking stoves in all the homes. Median I/O, P/I and P/O ratios for PM2.5 were close to unity, and for NO2 they ranged between 0.64 and 0.95. These ratios were probably due to high ambient PM2.5 and NO2 levels in Santiago, which diminished the relative contribution of indoor sources and subjects' activities to indoor and personal PM2.5 and NO2 levels.  相似文献   

16.
Weekly PM2.5 samples were simultaneously collected at a semi-residential (Tsinghua University) and a downtown (Chegongzhuang) site in Beijing from August 2001 through September 2002. The ambient mass concentration and chemical composition of PM2.5 were determined. Analyses including elemental composition, water-soluble ions, and organic and elemental carbon were performed. The annual average concentrations of PM2.5 were 96.5 microg m(-3) and 106.9 microg m(-3) at CGZ and HU site, respectively. More than 80% of the PM2.5 mass concentrations were explained by carbonaceous species, secondary particles, crustal matters and trace elements at the two sites. Carbonaceous species were the most abundant components, constituting about 45% and 48% of the total PM2.5 mass concentrations at CGZ and THU site, respectively. SO4(2-), NO3- and NH4+ were three major ions, accounting for 37%, 23% and 20%, respectively, of the total mass of inorganic water-soluble ions.  相似文献   

17.
In this study a set of 340 PM10 and PM2.5 samples collected throughout 16 months at rural, an urban kerbside and an industrial background site (affected by the emissions from the ceramic manufacture and other activities) were interpreted. On the regional scale, the main PM10 sources were mineral dust (mainly Al2O3, Fe, Ti, Sr, CaCO3, Mg, Mn and K), emissions derived from power generation (SO4=, V, Zn and Ni), vehicle exhausts (organic and elemental carbon, NO3- and trace elements) and marine aerosol (Na, Cl and Mg). The latter was not identified in PM2.5. At the industrial site, additional PM10 sources were identified (tile covering in the ceramic production, petrochemical emissions and bio-mass burning from a large orange tree cultivation area). The contribution of each PM source to PM10 and PM2.5 levels experiences significant variations depending on the type of PM episode (Local-urban mainly in autumn-winter, regional mainly in summer, African or Atlantic episode), which are discussed in this study. The results show that it would be very difficult to meet the EU limit values for PM10 established for 2010. The annual mean PM levels are 22.0 microg PM10/m3 at the rural and 49.5 microg PM10/m3 and 33.9 microg PM2.5/m3 at the urban site. The natural contribution in this region, estimated at 6 microg/m3 of natural mineral dust (resulting from the African events and natural resuspension) and 2 microg/m3 of marine aerosol, accounts for 40% of the 2010 EU annual limit value (20 microg PM10/m3). Mineral dust concentrations at the urban and industrial sites are higher than those at the rural site because of the urban road dust and the ceramic-production contributions, respectively. At the urban site, the vehicle exhaust contribution (17 microg/m3) alone is very close to the 2010 EU PM10 limit value. At the rural site, the African dust is the main contributor to PM10 levels during the highest daily mean PM10 events (100th-97th percentile range). At the urban site, the vehicle exhaust product is the main contributor to PM10 and PM2.5 levels during the highest daily mean PM events (100th-85th percentile range). Mineral dust concentrations during African dust events accounts for 20-30 microg/m3 in PM10 and 10-15 microg/m3 in PM2.5. During non-African dust events, mineral dust derived from anthropogenic activities (e.g. urban road dust) is also a significant contributor to PM10, but not to PM2.5.  相似文献   

18.
There are limited data describing pollutant levels inside homes that burn solid fuel within developed country settings with most studies describing test conditions or the effect of interventions. This study recruited homes in Ireland and Scotland where open combustion processes take place. Open combustion was classified as coal, peat, or wood fuel burning, use of a gas cooker or stove, or where there is at least one resident smoker. Twenty-four-hour data on airborne concentrations of particulate matter<2.5 μm in size (PM2.5), carbon monoxide (CO), endotoxin in inhalable dust and carbon dioxide (CO2), together with 2-3 week averaged concentrations of nitrogen dioxide (NO2) were collected in 100 houses during the winter and spring of 2009-2010. The geometric mean of the 24-h time-weighted-average (TWA) PM2.5 concentration was highest in homes with resident smokers (99 μg/m3--much higher than the WHO 24-h guidance value of 25 μg/m3). Lower geometric mean 24-h TWA levels were found in homes that burned coal (7 μg/m3) or wood (6 μg/m3) and in homes with gas cookers (7 μg/m3). In peat-burning homes, the average 24-h PM2.5 level recorded was 11 μg/m3. Airborne endotoxin, CO, CO2, and NO2 concentrations were generally within indoor air quality guidance levels. PRACTICAL IMPLICATIONS: Little is known about indoor air quality (IAQ) in homes that burn solid or fossil-derived fuels in economically developed countries. Recent legislative changes have moved to improve IAQ at work and in enclosed public places, but there remains a real need to begin the process of quantifying the health burden that arises from indoor air pollution within domestic environments. This study demonstrates that homes in Scotland and Ireland that burn solid fuels or gas for heating and cooking have concentrations of air pollutants generally within guideline levels. Homes where combustion of cigarettes takes place have much poorer air quality.  相似文献   

19.
Twenty-three hour measurements of PM(2.5) particulate matter have been carried out during the period between the 1st April and the 13th November 2003 in a suburban area of Athens. The monitoring site was located in the National Research Center "DEMOKRITOS", on the foot of Hemittos Mountain and about 12 km away from the center of Athens. The site covers an area of 600 acres in a forest of pine trees close enough to the newly constructed Hemittos Mountain peripheral highway. PM(2.5) samples were collected on 47 mm filters, with the use of low volume gravimetric samplers while a meteorological station recorded meteorological data 6 m above the ground, nearby the sampling instrumentation. The daily average PM(2.5) concentration reached 21.1 microg m(-3) and all measurements were below U.S. Environmental Pollution Agency daily limit (65 microg m(-3)). A regression analysis was used to investigate the relationship among PM(2.5) concentrations and meteorological parameters. Additionally, PM(2.5) mass concentrations were correlated with other inorganic gaseous pollutants (O(3), NO, NO(2), SO(2)) while weekly and seasonal PM(2.5) variations were also investigated.  相似文献   

20.
The indoor air quality of 27 primary schools located in the city centre and suburbs of Antwerp, Belgium, was assessed. The primary aim was to obtain correlations between the various pollutant levels. Indoor:outdoor ratios and the building and classroom characteristics of each school were investigated. This paper presents results on indoor and local outdoor PM2.5 mass concentrations, its elemental composition in terms of K, Ca, Ti, V, Cr, Mn, Fe, Ni, Cu, Zn, Br, Pb, Al, Si, S, and Cl, and its black smoke content. In addition, indoor and local outdoor levels of the gases NO2, SO2, O3, and BTEX (benzene, toluene, ethyl benzene, and xylene isomers) were determined. Black smoke, NO2, SO2 and O3, occurred at indoor:outdoor ratios below unity, indicating their significant outdoor sources. No linear correlation was established between indoor and outdoor levels for PM2.5 mass concentrations and BTEX; their indoor:outdoor ratios exceeded unity except for benzene. Classroom PM2.5 occurred with a different elemental composition than local outdoor PM2.5. The re-suspension of dust because of room occupation is probably the main contributor for the I/O ratios higher than 1 reported for elements typically constituting dust particles. Finally, increased benzene concentrations were reported for classrooms located at the lower levels. PRACTICAL IMPLICATIONS: The elevated indoor PM2.5, and BTEX concentrations in primary school classrooms, exceeding the ambient concentrations, raise concerns about possible adverse health effects on susceptible children. This is aggravated by the presence of carpets and in the case of classrooms at lower levels. Analysis of PM2.5's elemental composition indicated a considerable contribution of soil dust to indoor PM2.5 mass. In order to set adequate threshold values and guidelines, detailed information on the health impact of specific PM2.5 composites is needed. The results suggest that local outdoor air concentrations measurements do not provide an accurate estimation of children's personal exposures to the identified air pollutants inside classrooms.  相似文献   

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