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1.
淮安市区大气中颗粒物PM_(10)、PM_(2.5)污染水平   总被引:1,自引:0,他引:1  
通过对淮安市大气颗粒物中PM10、PM2.5的监测与污染水平分析,得出了淮安市区PM10与PM2.5浓度呈冬秋季高,夏春季低的特征。PM2.5和PM10的比值范围在0.62~0.65之间,即PM2.5在PM10以下颗粒物中所占比例大约为63%。  相似文献   

2.
大气污染与儿童肺功能的典型相关分析   总被引:2,自引:0,他引:2  
在 1 994~ 1 996年间 ,对污染点和对照点 (相对清洁点 )同时进行了大气污染 (气溶胶 ,二氧化硫等 )和儿童肺功能 (FVC,FEV1 ,FEF2 5~ 75 等 )的测定。对它们之间的关系进行了典型相关分析 ,其结果是肺功能指标和大气污染物呈负相关。统计分析提示污染点与对照点儿童肺功能的差别主要是由于大气污染 (气溶胶 )造成的 ,特别是 PM2 .5 的细粒子造成的。  相似文献   

3.
2015年10月15日—24日南宁市出现了一次典型的大气细颗粒物(PM2.5)污染过程,利用单颗粒气溶胶质谱仪和大气颗粒物激光雷达仪器进行监测,结合气象、后向轨迹及卫星遥感影像等资料分析大气污染成因及远距离传输对该次污染过程的影响。研究表明:此次南宁市大气污染以PM2.5超标为主,PM2.5日均质量浓度最高为85.2 μg/m3,超过标准值13.6%,其中PM1占PM2.5的66.3%。此次污染过程是由本地污染源与外来源影响互相叠加,在静稳、高温、强光等天气情况下发生协同作用引起的,污染物主要来源为燃煤源、机动车尾气源和生物质燃烧源,占全部来源的75.0%~80.0%。  相似文献   

4.
上海市城区典型居民住宅区PM2.5和PM10监测结果比较研究   总被引:1,自引:0,他引:1  
在上海市环境空气质量连续自动监测网络中的一个城市居民住宅区监测点进行了为期一年的PM2.5和PM10的同步监测,监测结果表明:PM2.5和PM10日平均浓度之间的比值范围为0.194~0.889,月平均浓度之间的比值范围为0.420~0.667;冬季颗粒物中小粒径颗粒物PM2.5的比例较高,春季则较低;随着相对湿度的上升;颗粒物中小粒径颗粒物PM2.5的比例缓慢升高;比值变化的风向特征与监测点周围环境情况有关;PM2.5和PM10监测结果月均值之间和各月的日均值之间均线性相关,回归直线关系存在。  相似文献   

5.
随着工业化和城市化进程的加速,大气气溶胶污染日趋严重,由气溶胶细粒子PM2.5污染造成的能见度恶化事件越来越多,中国东部地区灰霾天气迅速增加.灰霾天气的本质是细粒子气溶胶污染,与光化学污染相关联,形成灰霾天气的气溶胶组成非常复杂.近年来由于灰霾天气日趋严重引发的环境效应问题,以及气溶胶辐射强迫引发的气候效应问题,已引起科学界、政府部门和社会公众的广泛关注,成为热门话题.在此背景下,国家出台了新版《环境空气质量标准》(GB 3095-2012),增设PM2.5浓度限值,对环境监测、环境管理和环境评价提出了新的要求.通过分析中国大气污染背景、国际组织和其他国家的PM2.5标准,及近期热点问题,提出在环境监测、环境管理和环境评价过程中实施新标准,监控PM2.5的策略.  相似文献   

6.
为研究乌鲁木齐市冬季采暖期间大气颗粒物污染特征,通过采样和在线监测二种手段分析了2015年1~2月大气颗粒物样品,采用重量法分析颗粒物质量浓度,并对其相关性进行分析。结果表明:依据《环境空气质量标准》(GB 3095-2012),采样期间乌鲁木齐市大气PM_(10) 和PM_(2.5)的日均质量浓度均超过了国家二级标准,颗粒物污染严重;PM_(10) 和PM_(2.5)存在显著相关性,PM_(2.5)和PM_(10) 浓度的比值均大于0.5,采暖期PM2.5对乌鲁木齐市大气颗粒物贡献显著。  相似文献   

7.
大气颗粒物监测分析及今后研究课题   总被引:16,自引:4,他引:16  
概述了 PM1 0 和 PM2 .5今后的研究方向。目前我国尚未开展 PM2 .5的常规监测 ,PM1 0 的自动监测中尚存在一些技术问题 ,且尚未公布 PM1 0 自动监测的技术性标准 ,为了满足各级环境监测站的工作需求 ,在附录中介绍了国外关于PM1 0 和 PM2 .5的监测仪器和方法标准 ,并介绍了 2 0 0 0年日本颁布的 PM2 .5自动监测技术规定  相似文献   

8.
TSP-PM10-PM2.5-2型中流量大气颗粒物采集系统的开发和应用   总被引:13,自引:0,他引:13  
自行开发并研制了TSP-PM10-PM2.5-2型中流量TSP、PM10、PM2.5大气颗粒物采集系统,是目前中国唯一可以采集TSP、PM10、PM2.5样品并提供足够的样品量进行大气颗粒物化学成分分析的中流量大气颗粒物采集器.该系统精心设计和加工的限流孔可以保持完全固定的流量,保证切割粒径的稳定,减小采样的误差并方便操作.该系统已经成功地应用于20多个城市和地区大气颗粒物的监测和研究中,为研究大气颗粒物的污染状况和来源提供了有效的技术手段和支持.  相似文献   

9.
青岛市区春夏季大气能见度与颗粒物的关系   总被引:6,自引:0,他引:6  
利用青岛市灰霾综合观测站2012年3月2日-2012年6月7日期间的监测数据,分析了青岛市区大气能见度与不同粒径颗粒物质量浓度的日变化特征,比较了各级别大气能见度下不同粒径颗粒物质量浓度及所占比例的相关性,研究了相对湿度对大气能见度和颗粒物质量浓度相关性的影响.结果表明,监测时段大气能见度与颗粒物质量浓度呈现较好的负相关,每天大气能见度最低值出现在早晨07:00--09:00;剔除相对湿度高于90%的前提下,PM2.5是影响大气能见度的主要因子,随着其在PM1o中所占比例上升,大气能见度级别不断下降,相关系数为-0.84;不同相对湿度区间下,PM2.5对大气能见度的影响最明显,其中,相对湿度为60% ~ 70%,大气能见度与颗粒物质量浓度之间的相关性最好.  相似文献   

10.
灰霾天气不同粒径的颗粒物污染特征分析   总被引:2,自引:0,他引:2  
利用宁波市北仑区PM10、PM2.5和PM1的监测数据及与之对应的能见度监测结果,对影响灰霾天的颗粒物的污染特征进行了系统研究,结果表明,颗粒物粒径对灰霾天的形成和能见度的影响程度差异明显,且3种粒径的颗粒物质量浓度与能见度之间线性关系密切。  相似文献   

11.
河流沉积物中有机污染物的分析研究进展   总被引:8,自引:2,他引:6  
总结了近年来河流沉积物中有机污染物的研究进展 ,集中评述了国内有关沉积物中多环芳烃、有机氯农药和多氯联苯的分析研究现状 ,包括样品采集、样品前处理和样品分析 ,并对今后河流、湖泊及水库沉积物中污染物的分析工作作了展望  相似文献   

12.
Implementing good practice social impact assessment (SIA) that meets international standards in countries in transition is problematic. We reflect on the challenges faced when undertaking SIA in the Russian Federation. These challenges restrict meaningful SIA processes from being undertaken and limit public participation and the effective community engagement of project-affected local people. Based on the self-reflexive professional experience of two Russian-based social practitioners, and their discursive interactions with two leading academics in environmental and social impact assessment, as well as on in-depth interviews with prominent Russian and international experts, we identified the key challenges that prevent effective SIA from being implemented in Russia: a lack of understanding of the international standards; discrepancy in the determination of the social area of influence between the national requirements and international standards; difficulties in combining national and international impact assessment processes; and a tendency by companies to restrict stakeholder engagement to the minimum. We hope that by having an awareness of these limitations, improvements to SIA practice in Russia and elsewhere will be made.  相似文献   

13.
选取位于西藏拉萨的罗布林卡、龙王潭公园、布达拉宫广场,位于林芝的福建公园,以及位于昌都的天津广场等5个城市公园,于2017年5—6月采取样线法对其中的鸟类群落组成和外来鸟种情况进行调查。调查共记录到鸟类9目20科36种,其中属于古北界的有12种,东洋界和广布种也均为12种。36种鸟类中,留鸟24种,夏候鸟6种,冬候鸟2种,旅鸟4种。统计到外来鸟种4种,包括山噪鹛(Garrulax davidi)、八哥(Acridotheres cristatellus)、红嘴相思鸟(Leiothrix lutea)及大紫胸鹦鹉(Psittacula derbiana),占调查鸟种种类的11.1%,外来物种的入侵风险在高原不容忽视。  相似文献   

14.
Quantifying nickel in soils and plants in an ultramafic area in Philippines   总被引:1,自引:0,他引:1  
In this study, concentrations of nickel (Ni) were quantified in the soils and plants in the agricultural areas of Salcedo watershed in Eastern Samar Island, Philippines. The quantity of total Ni in soils (TS-Ni) was significantly high with a mean of 1,409 mg kg?1, while the soil available Ni (SA-Ni) was low with a mean of 8.66 mg kg?1. As the levels of TS-Ni in the Salcedo watershed greatly exceeded the maximum allowable concentrations for agricultural soils, the site is not suitable for agricultural purposes. Despite significant TS-Ni levels, SA-Ni levels were very low due to tight binding between Ni and soil components. Consequently, all plants investigated did not meet the criterion for a Ni hyperaccumulator plant with low Ni contents (mean TP-Ni of 14.7 mg kg?1). Comparison of Ni levels between food plants and its recommended daily intake (RDI) suggests that consumption of food-plants grown in the study area is unlikely to pose health risks. However, caution must be taken against combined consumption of food plants with high Ni levels or their prolonged consumption, as it can induce accumulation of Ni above RDI.  相似文献   

15.
Plants continue to be an important source of new bioactive substances. Brazil is one of the world’s mega-diverse countries, with 20 % of the world’s flora. However, the accelerated destruction of botanically rich ecosystems has contributed to a gradual loss of native medicinal species. In previous study, we have observed a fast and intensive change in trade of medicinal plants in an area of Amazon, where human occupation took place. In this study, we surveyed 15 public markets in different parts of Brazil in search of samples of 40 plants used in traditional medicine and present in first edition of Brazilian Official Pharmacopoeia (FBRAS), published in 1926. Samples of plants commercialized as the same vernacular name as in Pharmacopoeia were acquired and submitted to analysis for authentication. A total of 252 plant samples were purchased, but the laboratory analyses showed that only one-half of the samples (126, 50.2 %) were confirmed as the same plant species so named in FBRAS. The high number of unauthenticated samples demonstrates a loss of knowledge of the original native species. The proximity of the market from areas in which the plant occurs does not guarantee that trade of false samples occurs. The impact of the commerce of the substitute species on their conservation and in public health is worrying. Strategies are necessary to promote the better use and conservation of this rich heritage offered by Brazilian biodiversity.  相似文献   

16.
Concern about nitrogen loads in marine environments has drawn attention to the existence and possible causes of long-term trends in nitrogen transport in rivers. The present study was based on data from the Swedish environmental monitoring programme for surface water quality; the continuity of these data is internationally unique. A recently developed semiparametric method was employed to study the development of relationships between runoff and river transport of nitrogen since 1971; the observed relationships were then used to produce time series of flow-normalised transports for 66 sites in 39 river basins. Subsequent statistical analyses of flow-normalised data revealed only few significant downward trends (p 0.05) during the time period 1971–1994, and the most pronounced of these downward trends were caused by reduced point emissions of nitrogen. The number of significant upward trends was substantially larger (15 for total-N and 18 for NO3-N). Closer examination of obtained results revealed the following: (i) the most pronounced upward trends were present downstream of lakes, and (ii) observed increases in nitrogen transport coincided in time and space with reduced point emissions of phosphorus or organic matter. This indicated that changes in the retention of nitrogen in lakes were responsible for the upward nitrogen trends. The hypothesis that nitrogen saturation of forest soils has caused a general increase in the riverine export of nitrogen from forested catchments in Sweden was not confirmed. Neither did the results indicate that improved agricultural practices have reduced the export of nitrogen from agricultural catchments.  相似文献   

17.
As a part the Italian National Programme of Research in Antarctica (PNRA) a monitoring study has been undertaken to quantify the concentrations of some selected trace elements in human hair of participants in the Antarctic expeditions. Such concentrations may vary as a consequence of the extreme environmental conditions and changes in lifestyle experienced by participants in the expeditions, as some evidence in previous investigations seems to suggest. The present study regards samples collected on the occasion of the 2002-2003 expedition to the Italian Base of Terra Nova Bay (now Mario Zucchelli Base), i.e., just before the expedition and about one month later. Seven essential elements were taken into account, namely, Ca, Cu, Cr, Fe, Mg, Mn and Mo. Determinations were performed by Inductively Coupled Plasma Atomic Emission Spectrometry (ICP-AES) and Dynamic Reaction Cell Inductively Coupled Plasma Mass Spectrometry (DRC-ICP-MS). Data obtained were statistically treated by using the non-parametric Friedman test. The concentrations of Ca, Cu and Mg were found to decrease (P < 0.05). The stress caused by the severe environmental conditions might well play a role in the observed decrease.  相似文献   

18.
为调查丽水市空气中Pb污染现状,在机动车相对集中的市区布设5个测点,测点高度1.2m;监测周期为1a,每星期采样1d或2d,每天采集1个样,每次采样6h;监测项目为TSP、Pb;评价标准采用GB3095—1996《环境空气质量标准》。结果表明,丽水市各测点空气中Pb最大的季均值、年均值均未超标;常规测点和交通路口测点之间TSP、Pb质量浓度值均存在显著的差异性。  相似文献   

19.
HPLC法测定饲料中维生素A、维生素D 3 和维生素E   总被引:2,自引:0,他引:2       下载免费PDF全文
建立了以w(C2H5OH)=95 %乙醇直接提取,高效液相色谱仪在波长280 nm和254 nm处连续测定饲料中维生素A、维生素D3和维生素E的方法.色谱柱为大连依利特Hypersil ODS C18(25 cm×4.6 mm×5 μm),流动相为甲醇-水,流速为1.2 mL/min.维生素A、维生素D3、维生素E的质量浓度分别在1.0 mg/L~20.0 mg/L、0.5 mg/L~15.0 mg/L 、2.5 mg/L~50.0 mg/L范围内与峰面积呈良好的线性关系,检测限分别为0.3×10-6 μg、0.04×10-6 μg、5.0×10-6 μg,相对标准偏差分别为1.6 %、2.7 %、2.4 %,平均回收率分别为99 %、102 %、98 %.  相似文献   

20.
基于城市超级站对2018年12月—2019年2月南京市在线水溶性离子污染特征进行研究。结果表明:监测期间水溶性无机离子(WSIs)质量浓度均值为45.7μg/m3,占PM2.5的67.8%,各离子排序为NO3-> SO42->NH4+>Cl->K+>Ca2+>Na+>Mg2+。二次离子(SNA)是PM2.5主要组分,大气气溶胶呈中性。各离子日变化存在差异,SNA变化趋势和WSIs基本一致。南京市冬季存在明显SO2和NO2向SO42-和NO3-二次转化;NO3-/SO42-均值为1.96,移动源增量大于固定源。通过相关性和三相聚类分析可知,SNA主要结合方式为(NH4)2SO4和NH4NO3。主成分分析表明,南京市冬季PM2.5中水溶性离子主要来源是二次转化,燃煤、生物质燃烧和土壤建筑扬尘也有贡献。  相似文献   

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