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建立了固定污染源排气中三氟甲烷、四氟甲烷、六氟乙烷和六氟化硫的采样和气质联用分析方法,检出限分别为0.06、0.15、0.21、0.71 mg/m3,精密度在3.2%以下,相关系数大于0.999 6,并对浙江省内2家典型企业排放的温室气体进行了监测,实际样品监测结果表明,该方法能够满足废气中4种温室气体的监测要求。  相似文献   

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采用石墨炉原子吸收分光光度法、双道原子荧光光谱法研究乌鲁木齐市采暖期前期与后期不同粒径大气颗粒物(TSP、PM_(10)、PM_5、PM_(2.5))中Hg、As、Zn、Pb、Ni等5种重金属元素的质量浓度,并对重金属污染水平进行评价。Hg质量浓度为0.3~5.7 ng/m3;As质量浓度为15.3~122.5 ng/m~3;Zn质量浓度为298.0~1 686.5 ng/m~3;Pb质量浓度为0.5~88.8 ng/m~3;Ni质量浓度为10.4~25.5 ng/m~3。Igeo计算得出采暖期后期的TSP、PM_(10)、PM_5、PM_(2.5)中各重金属Igeo值均高于采暖期前期,其中Hg元素为严重污染;富集因子分析得出Hg、Zn元素的EFi值大于10,说明这些元素是人为源贡献。通过研究乌鲁木齐市不同时期、不同粒径大气颗粒物中各种重金属污染状况,为乌鲁木齐大气污染治理提供科学支持。  相似文献   

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The wildlife populations of northern Central African Republic (CAR) have long suffered intense uncontrolled hunting. Socio-political turmoil in northern CAR that started in 2002 resulted in a rebellion in 2006. An aerial sample count was carried out in northern CAR after the ceasefire to assess the impact of this troubled period on wildlife. The survey was flown at the end of the dry season in February-March 2010. It covered a landscape complex of 95,000?km2 comprising national parks, hunting reserves and community hunting areas. Comparison with earlier surveys revealed a dramatic decline of wildlife: the numbers of large mammals fell by 94% in 30?years, probably due to poaching, loss of habitat and diseases brought by illegal movements of cattle. Elephant (Loxodonta africana), Reduncinae and topi (Damaliscus lunatus) populations showed the greatest decline (each over 90%). Other species declined by 70-80% during the same period. The future of wildlife in this area is dark without a strong commitment to provide adequate funding and quickly implement of determined field management. Reinforced cooperation with neighbouring Chad and Sudan is required since they are facing similar problems.  相似文献   

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Until now, monitoring of large-scale regional funding programmes has been rare, although their large scope and abstract planning targets generally involve high levels of uncertainty. This study applies and examines a newly developed methodological approach for monitoring such programmes. It also critically reflects to what extent the Strategic Environmental Assessment (SEA) contributes to a better consideration of environmental sustainability and to a learning effect among the stakeholders as well as within the decision-making process. The interviews conducted during the SEA monitoring revealed a very low recognition of the SEA, and its content, among project applicants of the transnational regional funding programme. They further show that more information on the SEA and its recommendations to mitigate negative environmental impacts would be beneficial in the future. Overall, the monitoring confirmed, however, that the institutions responsible for the programme were aware of the benefits of considering environmental sustainability. The long-term application of SEA in an iterative process provided positive learning effects on environmental sustainability and awareness for environmental aspects. This study also shows how SEA monitoring can serve as a tool to enhance visibility and foster communication among decision makers and applicants.  相似文献   

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通过对苏州市近几年开展的突发环境事件应急预案编制工作的分析,总结了企业突发环境事件应急预案编制中存在的问题,探索了“十二五”期间突发环境事件应急预案规范化管理中面临的挑战,并结合实际提出了针对企业突发环境事件应急预案编制管理工作的一些建议。  相似文献   

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介绍了江苏省环境空气监测网络的构成和环境空气质量趋势监测点的优选方法。通过对1993年-2000年全省13个少辖市60个监测点的SO2、TSP监测结果的相关指标统计,分别优选出代表全省及省辖市的环境空气质量趋势监测点12个和25个。  相似文献   

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于2014-2019年,对上海市奉贤区4个环境空气自动监测站的臭氧(O3)污染特征及其影响因素监测数据进行了统计分析.结果表明,O3质量浓度年均值大体平稳且略呈下降趋势,O3日8 h质量浓度中位值和最大值呈现逐步上升趋势,O3质量浓度的最高点和次高点均出现在4-10月.气温与O3质量浓度呈显著正相关关系;随着风速和湿度...  相似文献   

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以和田市城区2014年采集的大气PM_(2.5)样品为实验对象,将0.1 g的PM_(2.5)样品膜与2-硫代巴比妥酸(0.2%)和三氯乙酸(20%)混合显色液反应,用可见光分光光度计测定反应产物的吸光度,通过正交实验来优化PM_(2.5)膜中丙二醛(MDA)的提取及测定条件,结果表明,在反应温度90℃、超声和加热时间40 min、显色剂用量为45 mL时,反应产物在532 nm处具有稳定的最大吸收峰。对和田市城区PM_(2.5)及MDA质量浓度的变化特征分析结果表明,和田市城区4个季节PM_(2.5)平均质量浓度由高到低顺序分别为春季(1 096.67±369.60)μg/m~3、夏季(1 016.16±708.00)μg/m~3、秋季(686.88±525.00)μg/m~3和冬季(214.54±94.70)μg/m~3。MDA平均质量浓度的变化范围为1.10~7.75 ng/m~3,其平均值最高为夏季(4.43±1.80)ng/m~3,最低为春季(1.42±0.60)ng/m~3,冬季与秋季相当,分别为(2.93±0.70)ng/m~3和(2.83±0.80)ng/m~3;最终,将PM_(2.5)膜中MDA的质量浓度与相应的TD_(30)(体外DNA氧化损伤达到30%的剂量)进行相关性分析得出,无论是全样还是水样的TD_(30)值均随MDA浓度的升高而呈降低的趋势。其中,全样与MDA质量浓度的相关性更为显著(r=-0.597,显著性P0.01)。  相似文献   

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为了解当前不同来源环境空气气态污染物(CO、SO2、NO)标气质量状况,选择12家主流气态污染物(CO、SO2、NO)标气制造商,分别匿名采购3种气态污染物标气,建立2家参考实验室共同测试的模式和计量溯源一致性评价方法,对标气进行测试后,采用En值法评价其定值准确性,同时评估其技术资料完整性。结果显示:12家制造商的72瓶有证标气中,有9瓶标气定值结果准确性评价为不合格,涉及5个制造商来源,其中NO作为反应性气体,不合格标气数量最多,占比达20.8%;12家制造商中8家技术资料完整。鉴于标准气体对气态污染物监测结果的准确性、可比性和可溯源性具有重要意义,建议进一步加强标气质量事中事后监管和行业评估,推动制造商不断提高标气生产水平。标气使用者则应尽量选择质量可靠的有证标气。  相似文献   

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建立了大气颗粒物(PM_(2.5)、PM_(10))中10种糖醇类物质的离子色谱检测法。建立了大气颗粒物(PM_(2.5)、PM_(10))中丙三醇、赤藓糖醇、木糖醇、左旋葡聚糖、山梨醇、甘露聚糖、海藻糖、甘露醇、半乳聚糖、葡萄糖的高效阴离子交换色谱(HPAEC)与脉冲安培检测器(PAD)联用技术(HPAEC-PAD)的快速检测法。样品采用2 mg/L叠氮化钠溶液60 min振荡提取,经浓度为250 mmo L/L,流速为0.40 m L/min的氢氧化钠淋洗液洗脱30 min后,浓度逐步增加,60 min时达到500 mmol/L,10种物质被完全洗脱。该方法线性良好,线性回归系数大于0.999,实际样品测试加标回收率为84%~115%,精密度为0.5%~8.2%,对北京市2016年1月采暖季的大气颗粒物样品(PM_(2.5)、PM_(10))进行检测,其中左旋葡聚糖质量浓度最高,分别为(113±124)ng/m~3,(118±100)ng/m~3,其他9种物质均有检出。  相似文献   

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基于LS-SVR、BP-ANN和MLR模型的PM10浓度预测   总被引:1,自引:0,他引:1  
利用宁东能源化工基地PM10和气象监测数据,分别采用LS-SVR、BP-ANN和传统MLR模型预测PM10浓度变化。结果表明,较BP-ANN模型、MLR模型,LS-SVR模型能更好地刻画PM10浓度与各气象因素间的非线性相依关系,更准确地预测PM10浓度。  相似文献   

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南京市臭氧、VOCs和PANs污染特征及变化趋势   总被引:1,自引:0,他引:1  
对2013—2016年基于国家环境空气质量监测站以及省建大气多参数站所获取的南京市O_3、NO_2、CO、VOCs、PANs观测结果进行综合评价,结果表明:2016年南京市O_3第90百分位日最大8 h平均质量浓度比2013年上升33.3%,超标天数中O_3引起的超标占比增至32.0%。南京市区大气中非甲烷总烃冬季浓度高于夏季,含氧挥发性有机物则与之相反;在5—9月,含氧挥发性有机物组分在日变化过程中出现峰值的时间先后顺序依次为醚、醛、酮类,且O_3和过氧乙酰硝酸酯(PANs)生成存在有一定的线性关系。VOCs/NOx比值表明南京市处于VOCs控制区,因此对NO_2浓度下降不敏感,植物源挥发性有机物连续3年上升,夏季大气光化学反应活性未显著下降,这些现象是城市O_3浓度维持在较高水平的重要因素。  相似文献   

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The applicability of environmental scanning electron microscopy (ESEM; imaging of hydrated samples) and conventional high vacuum scanning electron microscopy (SEM; imaging of dried samples at high vacuum) for the observation of natural aquatic colloids and particles was explored and compared. Specific attention was given to the advantages and limitations of these two techniques when used to assess the sizes and morphologies of complex and heterogeneous environmental systems. The observation of specimens using SEM involved drying and coating, whereas ESEM permitted their examination in hydrated form without prior sample preparation or conductive coating. The two techniques provided significantly different micrographs of the same sample. SEM provided sharper images, lower resolution limits (10 nm or lower), but more densely packed particles, suggesting aggregation, and different morphological features than ESEM, suggesting artefacts due to drying. ESEM produced less easily visualised materials, more complex interpretation, slightly higher resolution limits (30-50 nm), but these limitations were more than compensated for by the fact that ESEM samples retained, at least to some extent, their morphological integrity. The results in this paper show that SEM and ESEM should be regarded as complementary techniques for the study of aquatic colloids and particles and that ESEM should be more widely applied to aquatic environmental systems than hitherto.  相似文献   

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