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1.
为了解唐山市大气气溶胶中有机物的污染现状,于2010年9月—2011年8月利用安德森8级撞击采样器在河北省唐山市采集了大气颗粒物样品,采用GC/MS法对细粒子(PM_(2.1))和粗粒子(PM_(2.1))中的19种(C14—C32)正构烷烃进行了定量分析.结果表明,PM_(2.1)和PM_(2.1)中正构烷烃年均浓度分别为632.6 ng·m~(-3)和445.6 ng·m~(-3),主要富集在细粒子中,质量浓度季节变化规律为冬春秋夏;细粒子中,春、夏、秋、冬主峰碳(Cmax)分别为C29、C27、C21和C21;粗粒子中,春、夏、秋、冬Cmax分别为C31、C27、C22和C22,粗细粒子中碳优势指数(CPI)在1左右,说明唐山地区正构烷烃的污染主要受人为源影响很大.粗细粒子植物蜡贡献率分别为2.19%—57.62%和0.83%—49.87%,夏季植物蜡分布值最大,冬季最小,表明夏季植物源对正构烷烃的贡献相对较大,冬季正构烷烃的排放主要来源于人为活动(汽车尾气、化石燃料燃烧等),植物源贡献相对较少.  相似文献   

2.
焦炉排放大气颗粒物中正构烷烃的初步研究   总被引:2,自引:0,他引:2  
本文报告焦炉排气大气中可吸入尘(>15μm)上正构烷烃的排放量,分析了不同粒径颗粒物上21种正构烷烃的浓度,表明这些化合物的量随着烷烃碳数的增加呈正态分布;每种烷烃的量和颗粒物的空气动力学直径的对数呈正态分布关系。  相似文献   

3.
焦作市大气颗粒物中水溶性砷的分布特征   总被引:1,自引:0,他引:1  
利用原子荧光法对焦作市春、夏、秋、冬四季不同粒径大气颗粒物中水溶性重金属砷的分布特征及时空变化进行分析研究。研究表明:焦作市水溶性砷主要富集在PM2.1中,且颗粒物粒径越小,其富集砷的能力就越强,各级颗粒物中4级、5级、6级(0.41~2.1μm)范围内砷的含量最高,其总含量约为5.71~19.96 ng/m3,三者在不同月份所占比例高达73%~86%;由于形成机制与影响条件不同,不同粒径大气颗粒物中砷表现出明显的季节变化特征,总体趋势为冬季〉秋季〉夏季〉春季,主要原因为冬、夏季燃煤量增加,春季大气污染源减少,地表植被覆盖密集,空气环境质量较好;燃煤是焦作大气中砷的主要来源之一,且其对大气细颗粒物(粒径≤2.1μm)中砷的贡献最明显。  相似文献   

4.
汞在不同粒径大气颗粒物中的分布   总被引:7,自引:0,他引:7  
采用DFG 1型五段分级采样装置及冷蒸汽原子荧光法 ,对北京市冬、春、夏和秋季不同粒径大气颗粒物 (分别为≤ 1 1μm ,1 1— 2 0 μm ,2 0— 3 3μm ,3 3— 7 0 μm和≥ 7 0 μm )中的汞进行分析 .结果表明 :北京大气颗粒物中汞的浓度在 0 6 0— 3 95ng·m-3 之间 ,冬季平均浓度为 2 85ng·m-3 ,远大于其它季节 ;大气颗粒物中的汞呈双峰分布 ,在≤ 1 1μm的细颗粒和粗粒径处各有一峰值 ;北京大气颗粒物中的汞主要分布在≤ 1 1μm的细颗粒中 ,不同粒径颗粒物中汞的分布随季节变化而变化 ,冬季各粒径颗粒物中汞的浓度比其它季节高 ;大气颗粒物中汞的质量中值粒径 (MMD )冬季为 0 71μm ,其它季节均大于1 0 μm ;北京大气颗粒物中的汞至少有 5 0 %可进入人体呼吸系统 ,且冬季最为严重  相似文献   

5.
煤矿区大气降尘饱和烃分布特征   总被引:1,自引:0,他引:1  
煤矿区域粉尘较多,大气环境状况较差。应用GC-MS技术鉴定平顶山市石龙区降尘样品中饱和烃组分,分析其样品中正构烷烃的分布特征,并结合生物标志物参数解析其来源。结果表明,降尘样品中共鉴定出nC11~nC35正构烷烃、34种萜类化合物和18种甾烷化合物,还有二环倍半萜烷、烷基环己烷系列和丰富的姥鲛烷和植烷。正构烷烃碳数主要呈三峰态和双峰态分布,其碳优势指数CPI值分布在1.45~3.78之间。生物标志物参数C29甾烷20S/(20S 20R)值范围是0.34~0.40,C31霍烷22S/(22S 22R)值范围是0.54~0.59。由正构烷烃碳数分布特征和植物蜡碳数Cn(wax)分布特征、以及CPI值、甾烷和萜烷标志物参数值等分析认为,石龙区降尘饱和烃具有自然源与人为源双重来源。煤的普遍存在与其开采、加工活动密集是其最大的人为来源,而较明显的生物来源则可能为生物质碎屑或磨脱颗粒,或者是由于粗大的大气颗粒物易富集生物源正构烷烃所致。  相似文献   

6.
本文采用聚氨基甲酸乙酯泡沫和玻璃纤维滤膜,同时采集大气中气态和颗粒物样,用高效液相色谱和气相色谱分别测定了蒽、、、芘、苯并(a)、二苯并(a、h)葱、苯并(ghi)与C_(16)~C_(33)正构烷烃等有机污染物的含量。并得到了冬夏两季颗粒物和气态中有机污染物的分布规律。  相似文献   

7.
利用乌鲁木齐市中心区域气象局和黑山头2013年1月1日-2014年2月28日期间Grimm180在线监测数据,对乌鲁木齐市大气气溶胶数浓度和PM_(2.5)质量浓度的分布特征及其影响进行了分析,为深入了解乌鲁木齐市颗粒物污染现状,确定乌鲁木齐市大气污染治理重点,制定大气污染防治规划提供依据。结果表明,(1)气象局和黑山头气溶胶数浓度分布趋势一致,0.25~0.28μm之间的粒子数浓度最大;整体趋势表现为双峰型,第1峰出现在0.30~0.35μm之间,峰值分别为467.0和455.4 particle·cm~(-3);第2峰出现在4.0~5.0μm之间,峰值较小;粒径小于2.5μm的粒子数占到了粒子总数的99.88%;在粒径0.25~0.45μm范围内冬季气溶胶粒子数浓度最高,在粒径0.45μm范围内秋季气溶胶粒子数浓度最高;在粒径0.25~1μm范围内夏季气溶胶粒子数浓度最低,在粒径1μm范围内冬季数浓度最低;0.25~0.5μm粒径段内粒子占粒子总数的比例大小顺序为冬春夏秋;0.8~2.5μm之间不同粒径段的粒子占粒子总数的比例大小顺序为夏秋春冬;PM_(2.5)数浓度小时变化采暖期表现为双峰型,非采暖期为不太明显的三峰型。(2)观测期间气象局和黑山头PM_(2.5)平均质量浓度分别为61.77,43.42μg·m~(-3),日平均值超标率分别是30.81%和16.44%。采暖期气象局PM_(2.5)质量浓度小时变化呈现单峰,在19:00─21:00出现峰值;黑山头则呈现双峰,在6:00-8:00出现峰值,20:00出现一个不太明显的小峰;非采暖期气象局与黑山头PM_(2.5)质量浓度小时变化趋势一致,均表现为双峰型。两个站点PM_(2.5)质量浓度的季节变化均表现为冬季秋季春季夏季,特殊的地理位置和不同季节污染源的排放强度、气象条件是导致PM_(2.5)质量浓度随季节变化的主要原因。  相似文献   

8.
北京大气颗粒物碳质组分粒径分布的季节变化特征   总被引:7,自引:0,他引:7  
为了解有机碳(OC)和元素碳(EC)在北京大气颗粒物中的季节变化、粒径分布和来源,于2010年3月—2011年2月采用惯性撞击分级采样器采集大气颗粒物样品,热光碳分析仪测定其中有机碳和元素碳质量浓度.结果表明,OC在粗细粒子中含量相当,EC主要存在于细粒子中,在<2.1μm颗粒物中分别占(52±11)%和(70±22)%.OC存在明显的季节变化,冬、夏季高于春、秋季,而EC则表现为冬、秋季大于春、夏季.OC和EC粒径分布呈"双峰型",细粒子段峰值分别位于0.43—1.1μm和0.43—0.65μm,粗粒子段峰值均位于4.7—5.8μm.四季峰值对应的粒径段、峰宽和峰高存在差异.OC与EC粒径分布和相关性的季节变化表明,冬季OC与EC的主要来源为燃煤排放,夏季EC的主要来源为机动车尾气.  相似文献   

9.
为了解南京北郊大气颗粒物中含氮二次水溶性离子组分特征,2014年冬春两季使用Anderson 9级采样器对南京北郊大气颗粒物进行分级采样,利用离子色谱仪分析得到了各粒径范围颗粒物中的含氮二次无机组分质量浓度,结合能见度、相对湿度、颗粒物浓度等观测数据探讨了不同天气状况下大气颗粒物中含氮二次水溶性离子组分的含量及其粒径分布特征。结果表明:冬季和春季平均PM_(2.5)质量浓度分别达到了80.81μg·m~(-3)和52.57μg·m~(-3),明显超过二类标准限值。PM_(10)中NO_3~-和NH_4~+表现出较好的一致性,相关系数高达0.92,表明两种离子的来源比较相似;NO_2~-与NO_3~-和NH_4~+均呈现明显的负相关关系。就季节平均而言,冬季NO_3~-和NH_4~+质量浓度明显高于春季,尤其在0.43~2.1μm粒径范围内,这与冬季二次细颗粒物污染加剧有关;其他粒径段的浓度值季节差异不明显。不同能见度下,NO_3~-和NH_4~+质量浓度谱均呈三峰分布;当水平能见度3 km时,NO_3~-和NH_4~+最大谱峰大多在9.0~10μm粗粒径段;能见度降至3 km以下时,谱最大峰值出现在1.1~2.1μm粒径段。能见度水平越低,NO_3~-和NH_4~+的质量浓度越高,表明随着NO_3~-和NH_4~+浓度增加气溶胶的消光作用有所增强,从而导致能见度降低。霾天细模态中NH_4~+和NO_3~-的浓度较非霾天明显增加,粗模态无明显变化。NO_2~-作为中间产物其性质极不稳定,谱分布也比较复杂,但任何天气状况下均在粗粒径段出现高峰值。  相似文献   

10.
唐卓悦  卢迪  沈振兴  雷亚莉 《环境化学》2021,40(12):3714-3720
可溶性铁(Fe)一方面作为营养元素影响着生物地球化学循环,另一方面作为氧化剂对大气二次气溶胶的形成也有重要影响.本文分别开展了西安市混合功能区冬夏季不同粒径大气颗粒物的观测研究,通过使用改良的液体波导毛细管池(LWCC)测定颗粒物中酸性介质提取的可溶性铁浓度,并探究其季节变化、昼夜分布及粒径分布特征.季节分布特征表明,可溶性Fe(Ⅱ)浓度冬季高于夏季,而可溶性Fe(Ⅲ)浓度则夏季高于冬季.不同价态的可溶性Fe的季节分布特征差异明显,白天PM2.5中可溶性Fe(Ⅱ)和总可溶性性Fe的质量浓度和溶解度都大于夜晚的PM2.5样品,Fe(Ⅲ)则白天与夜晚无明显区别.粒径分布结果表明,溶解性Fe主要分布在细颗粒物中,且大气颗粒物的粒径越小,Fe(Ⅱ)sol与Fe(Ⅱ)total之比的变化范围越大,可溶性Fe(Ⅱ)和Fe(Ⅲ)之间的转化更为活跃.  相似文献   

11.
成都市大气颗粒污染物与气象要素的关系   总被引:3,自引:0,他引:3  
通过对2004年成都市API指数及API>100日数百分数的再分析,探讨了大气颗粒物污染季节分布、区域分布状况与气象要素的相互关系,并尝试用因子分析法研究了污染物浓度年际变化与气象因子的关系。研究表明,大气污染的季节分布为冬季>春季>秋季>夏季;API>100时数百分数的季节变化状况为春季>冬季>秋季>夏季,区域分布为城西北>城东>城北>城中心>城东南>城西>城南。城市发展对风向的改变比较明显,对风速的改变不明显。大气颗粒污染物年际变化与气象因子的相关性研究表明,PM10浓度与SO2、NOX、湿度、气压呈正相关,与风速、蒸发量、温度呈负相关关系。  相似文献   

12.
通过测试上海市区与郊区2008年4月—2009年3月的降水样品中的主要离子浓度值,分析了各离子的浓度变化特征和来源。结果发现:市区总离子浓度值为冬季〉秋季〉春季〉夏季,各离子平均浓度值为SO4^2-〉Ca^2+〉NH4〉Cl^-〉NO3^-〉Na^+〉Mg^2+〉F^+〉K^+;郊区总离子浓度值为秋季〉冬季〉春季〉夏季,各离子平均浓度值为SO4^2-〉NH4〉Ca^2+〉Cl^-〉Na^+〉NO3^-〉Mg^2+〉F^-〉K^+。经定量探源分析,发现降水中离子浓度受人为活动影响严重,市区、郊区降水离子的人为源分别占离子总量的76.8%和71.7%。阴离子中,市区与郊区SO4^2-的人为源所占比例均为最高,cl一的海源大于人为源,且郊区海源比例比市区高10.5%;NO3^-、F^-等均来自人为源。阳离子中,K^+以陆源为主,市区有部分为人为源;Ca^2+以人为源为主,且市区人为源比例高于郊区;Mg^2+以陆源为主,且市区所占比例小于郊区。  相似文献   

13.
The development of industry in Beijing, the capital of China, particularly in last decades, has caused severe environmental pollution including particulate matter (PM), dust–haze, and photochemical smog, which has already caused considerable harm to local ecological environment. Thus, in this study, air particle samples were continuously collected in August and December, 2014. And elements (Si, Al, V, Cr, Mn, Fe, Ni, Cu, Zn, Mo, Cd, Ba, Pb and Ti) and ions (\({\text{NO}}_{3}^{-}\), \({\text{SO}}_{4}^{2-}\), F?, Cl?, Na+, K+, Mg2+, Ca2+ and \({\text{NH}}_{4}^{+}\)) were analyzed by inductively coupled plasma mass spectrometer and ion chromatography. According to seasonal changes, discuss the various pollution situations in order to find possible particulate matter sources and then propose appropriate control strategies to local government. The results indicated serious PM and metallic pollution in some sampling days, especially in December. Chemical Mass Balance model revealed central heating activities, road dust and vehicles contribute as main sources, account for 5.84–32.05 % differently to the summer and winter air pollution in 2014.  相似文献   

14.
Urban green space, particularly the tree canopy, plays an important role in potential mitigation against atmospheric particulate pollution and protecting human health. In this study, current and future air particulate matter [including total suspended particulate (TSP), particulate matter 10 (PM10), and particulate matter 2.5 (PM2.5)] removal by the urban tree canopy of Beijing was estimated. A modeling approach was used based on the distributed measurement evaluation and a modified version. The urban tree canopy of Beijing, including mostly Platycladus sp., Pinus sp., Quercus sp., Robinia pseudoacacia, and economic forests, currently removes about 8.33 million kg/a air particulates, in which TSP accounted for 4.51 million kg/a, PM10 accounted for 2.74 million kg/a, and PM2.5 accounted for 1.08 million kg/a. The study on the removal of air particulates by different aged tree canopies showed that in coniferous trees, the ability to capture air particulates changed in the order of mature and over-mature > near-mature forest > young forest; in broadleaf forest, the ability changed in the order of near-mature forest > mature and over-mature > young forest. For total particulate matter, the biggest contribution was coarse particulates (60.74%); the contribution rate of fine particulates was different owing to different tree species groups. The results suggested that the ability of different trees to capture particles and age of forests varied widely and that suitable trees should be chosen to enhance pollution mitigation for city greening. © 2018 Science Press. All rights reserved.  相似文献   

15.
We examined larval mesopelagic fish assemblages, their distribution, and seasonal occurrence patterns in the Kuroshio–Oyashio transition region of the western North Pacific where complex hydrographic structures are observed due to the confluence of the Kuroshio Extension and Oyashio current. Larvae of the dominant families Myctophidae, Gonostomatidae, Bathylagidae, Sternoptychidae, and Phosichthyidae were represented by 31 species or types belonging to 24 genera. Based on species composition analysis using the Morishita–Horn similarity index, five assemblages were recognized: Oyashio, Spring Transition, Summer Transition, Kuroshio, and Slope Water assemblages. The distribution patterns of these assemblages corresponded closely with hydrographic structures such as position of the Oyashio and Kuroshio Extension fronts, warm core rings and streamers. Spring Transition (April) and Summer Transition (July–October) assemblages were the most important larval assemblages in the transition region. Larval abundances were low during late autumn and winter. The Spring Transition and Summer Transition assemblages were composed of subtropical, transitional, subarctic, and slope-water species, suggesting the importance of the transition region as nursery grounds of mesopelagic fishes of various origins from subarctic to subtropical waters. Larval fish transport by the Kuroshio, Oyashio, and Tsugaru Warm currents into the transition region is discussed.  相似文献   

16.
曲霉WZ-2对染料脱色研究   总被引:6,自引:1,他引:6  
从废水池污泥中分离到一株染料脱色曲霉WZ-2,它对不同染料均有较好的脱色效果。在33 ̄40℃温度范围内WZ-2对活性桃红KD-8B的脱色率为84% ̄98%,最佳脱色温度为33℃,pH值在4.0 ̄7.0范围内WZ-2对直接耐晒翠蓝GL的脱色率为83% ̄96%,最佳脱色pH为6.0,碳源、氮源及接种量对其脱色率均有影响,染料脱色物的紫外-可见光谱分析表明,可见光区520nm处的吸收峰完全消失,而紫外光  相似文献   

17.
渤海典型海域表层沉积物正构烷烃特征比较   总被引:2,自引:0,他引:2  
韩雪  马启敏  周华  程海鸥 《环境化学》2012,31(9):1315-1320
对渤海典型海域表层沉积物正构烷烃特征进行比较研究.分别采集葫芦岛市近岸海域(1#)、东营市近岸海域(2#)、营口市近岸海域(3#)9个站点的表层沉积物样品,经索氏提取、柱净化后进行GC-MS分析.结果表明,各站位都表现为双峰型,显示了陆源与海源双重贡献特征,但主导峰各不相同;正构烷烃含量(∑n-alk)均值分别为5.43μg.g-1、2.27μg.g-1、4.30μg.g-1;三海域碳优势指数CPI、奇偶优势指数OEP、姥鲛烷和植烷比值Pr/Ph等特征比值基本相同,指示混合来源及中性偏氧化的沉积环境;C31/C19均值分别为11.19、4.51、6.73,短/长链比值L/H均值分别为0.50、1.48、1.31,类脂物比值TAR均值分别为3.61、1.03、1.19,综合显示葫芦岛市近岸海域正构烷烃来源主要为陆源高等植物,而营口及东营近岸海域沉积物正构烷烃更多来源于内生浮游生物源及石油源,三海域沉积物受人类污染影响程度从高到低分别为2#海域(东营)>3#海域(营口)>1#海域(葫芦岛市),且东营近岸海域沉积物受石油污染特征明显.这些特征都与3个海域周边城市发展与污染输入特征有直接的关系.  相似文献   

18.
Gammarus oceanicus Segerstråle, 1947 and Echinogammarus marinus (Leach, 1815) were sampled during the breeding season from Oslofjord in 1984, and their lipid composition examined in relation to reproductive condition. In G. oceanicus, female lipid content increased as the ovary matured. Both the amount of lipid stored and the rate of accumulation were greater in spring than in winter. Spring eggs contained 12.4 g lipid, of which 63% was triacylglycerol and 27% phospholipid. Both fractions decreased steadily during embryonic development. Winter eggs contained 19.2g lipid, of which 52% was triacylglycerol and 43% phospholipid. During the early stages of embryonic development the amount of phospholipid decreased sharply, whereas that of triacylglycerol increased, suggesting that some of the fatty acid released from phospholipid was sequestered temporarily as triacylglycerol. When newly spawned, both winter and spring eggs were richer in monoenoic fatty acids than adult amphipods and these acids were the major fuel consumed during development. 6 fatty acids were utilised more slowly than 3 acids, and egg carotenoid pigment content remained constant. Female E. marinus increased in lipid content as the ovary matured. Spring eggs contained 14.7 g lipid when newly spawned and this increased to 16.6 g during the early stages of development. This increase was entirely triacylglycerol, which declined in later stages; the source of the extra lipid was unclear. Eggs contained very little phospholipid or sterol, and both of these components remained at a steady low level during development. E. marinus eggs were not significantly rich in thonoenoic acids compared with adults, and saturated, monoenoic and polyenoic acids were utilised about equally during development. Both adults and eggs were rich in 20.46, which was utilised at a slower rate than the 3 polyunsaturated acids during embryonic development; again, egg carotenoid pigment content remained constant. In both species there was a decrease in the size of the egg (and as a result, of the newly hatched juvenile), but an increase in total reproductive output (i.e., the total weight of the egg clutch) per female as the breeding season proceeded. The reproductive output of an individual female is probably related to food availability during the period of ovarian maturation, whereas the size of an individual egg is dictated largely by feeding conditions for the juveniles once they are independent of the female. The different patterns of lipid utilisation during development found in this study emphasize the flexibility of response in the reproductive biology of gammarid amphipods. It is not yet possible, however, to relate the differing patterns in a simple way either to egg size or total female reproductive output. Two outstanding problems are the source of extra triacylglycerol during the early stages of development of E. marinus and the metabolic cost of brooding eggs.  相似文献   

19.
Health risks associated with inhalation of fine particulate matter of 2.5 µm in diameter or smaller depend on their atmospheric levels and physicochemical properties. The relationships between chemical compositions and genotoxic activities of particles emitted by mineral industries, traffic and urban sources during summer and winter in the region of Provence-Alpes-Côte d'Azur (France) were investigated.

The fine particles were separated in respect to water-soluble (13 minerals and metals) and organic-extractable (16 polycyclic aromatic hydrocarbons) components that were quantified. The chromosome damaging properties of the hydrophilic and lipophilic extracts were assessed using the centromeric micronucleus assay on a human lung fibroblast cell line.

The composition of the fine particulate matter was variable and depended upon the sources and seasons. Both the hydrophilic and lipophilic extracts induced chromosome damage: (1) in hydrophilic extracts, Ca and Zn affected chromosome losses induction; (2) acenapthylene affected chromosome damage (breakages and losses) induction and naphthalene affected chromosome damage and losses induction in lipophilic extracts without metabolic activation; and (3) benzo[a]pyrene affected chromosome losses induction in lipophilic extracts with metabolic activation. Fine particulate matter arising from coal-fired power station, road traffic, and other urban sources were the most efficient to induce chromosome breakage.  相似文献   


20.
Arsenic is present in airborne particulate material released by coal-fired power plants and non-ferrous metal smelters. We have assessed whether the physico-chemical properties of arsenic in such particles play a role in its lung retention and uptake by the body. Female hamsters were given a single intratracheal instillation of fly ash or copper smelter dust suspensions (at doses of 50 or 100 g As kg–1) or identical amounts of soluble tri- and pentavalent arsenic, in the presence or absence of an inert dust material (tungsten carbide). The concentration of the element was measured in a 24 hour urine sample collected on the 1st, 2nd and 6th day after treatment and arsenic remaining in lung tissue was determined at the end of the same time periods. Both lung retention and urinary As excretion indicate a prolonged contact of the lung tissue with particulate As in contrast to soluble As salts. In addition to the effect of solubility described here, more research is needed to determine the effect of particle size and lung loading on retention, as well as the potential differences in the lung inflammatory response using arsenic-rich particulates from various sources.  相似文献   

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