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71.
Yao Meng Junwei Song Lewei Zeng Yingyi Zhang Yan Zhao Xufei Liu Hai Guo Liuju Zhong Yubo Ou Yan Zhou Tao Zhang Dingli Yue Senchao Lai 《环境科学学报(英文版)》2022,34(1):104-117
We present the continuously measurements of volatile organic compounds(VOCs) at a receptor site(Wan Qing Sha, WQS) in the Pearl River Delta(PRD) region from September to November of 2017. The average mixing ratios of total VOCs(TVOCs) was 36.3 ± 27.9 ppbv with the dominant contribution from alkanes(55.5%), followed by aromatics(33.3%). The diurnal variation of TVOCs showed a strong photochemical consumption during daytime,resulting in the formation of ozone(O3). Five VOC sources were ... 相似文献
72.
基于生态环境监测和气象观测数据,分析了2016~2020年京津冀13个城市臭氧(O3)浓度特征,讨论了O3污染高发月份日最高温度(Tmax)、日均地面气压(p)、日均地面相对湿度(RH)和日均地面风速(v)等气象要素对O3-8h浓度和O3-8h超标情况的影响规律,并采用AQI级别预报准确率、O3浓度范围预报准确率和O3级别预报准确率等方法,评估了基于神经网络的O3统计预报效果.结果表明,2016~2020年期间京津冀13城市ρ(O3-8h-90per)分别为157.4、177.2、177.3、190.6和175.6μg·m-3,区域臭氧浓度5a上升了11.6%,2016~2019年期间总体呈波动上升趋势,2020年环比下降;2020年与2016年相比,除北京、张家口和承德略有下降外,其他10个城市ρ(O3-8h-90per)上升了6~45.5μg·m-3.O3-8h月均值呈现"两头低,中间高"现象,ρ(O3-8h)在4~9月的月均值超过了100 μg·m-3,在6月最高,为158.10 μg·m-3.城市O3-8h超标率范围为8.6%~19.2%,97.8%的O3-8h超标情况发生在4~9月.区域尺度上O3-8h浓度与日最高温度相关性最强,当Tmax在25~28℃区间时,所有城市开始出现O3-8h超标.O3-8h浓度与日均地面气压呈负相关关系;当RH在60%以下时,大部分城市O3-8h浓度随相对湿度上升缓慢增长;当RH在61%~70%以上时,大部分城市O3-8h浓度随日均相对湿度上升而下降.O3-8h超标时的地面主导风向主要为偏南风,大部城市O3-8h浓度高值易集中出现在2~3m·s-1及以下低风速区间.OPAQ统计模式提前1~9 d预报相关系数范围为0.72~0.86,AQI级别预报平均准确率为67%~86%,O3-8h浓度范围预报平均准确率为63%~84%.在O3-8h超标情况多发的4~9月,模式对O3轻度污染和O3-8h超标情况提前3 d预报准确率分别为69%和66%,可为O3-8h超标管控提供参考依据. 相似文献
73.
Spatial variability of organochlorine pesticides (DDTs and HCHs) in surface soils from the alluvial region of Beijing, China 总被引:1,自引:0,他引:1
ZHANG Hong-yan GAO Ru-tai HUANG Yuan-fang JIA Xiao-hong JIANG Shu-ren 《环境科学学报(英文版)》2007,19(2):194-199
The spatial variability in the concentrations of 1,2,3,4,5,6-hexachlorocyclohexane (HCH) and 1,1,1-trichloro-2,2-bis-(p-chlorophenyl) ethane (DDT) in surface soils was studied on the basis of the analysis of 131 soil samples collected from the surface layer (0-20 cm depth) of the alluvial region of Beijing, China. The concentrations of total HCHs (including α-, β-, γ-, and δ-isomers) and total DDTs (i ncluding p,p'-DDT, p,p'-DDD, p,p'-DDE, and o,p'-DDT) in the surface soils tested were in the range from nondetectable to 31.72 μg/kg dry soil, with a mean value of 0.91, and from nondetectable to 5910.83 μg/kg dry soil, with a mean value of 32.13,respectively. It was observed that concentrations of HCHs in all soil samples and concentrations of DDTs in 112 soil samples were much lower than the first grade (50 μg/kg) permitted in "Environment quality standard for soils in China (GB15618-1995)". This suggests that the pollution due to organochlorine pesticides was generally not significant in the farmland soils in the Beijing alluvial region. In this study, the spatial distribution and trend of HCHs and DDTs were analyzed using Geostatistical Analyst and GS (513).Spatial distribution indicated how these pesticides had been applied in the past. Trend analysis showed that the concentrations of HCHs,DDTs, and their related metabolites followed an obvious distribution trend in the surface soils from the alluvial region of Beijing. 相似文献
74.
为了确定煤与瓦斯突出矿井的突出危险区域,威胁区域和安全区域,提出基于地质动力区划的多因素模式识别概率预测方法预测煤与瓦斯突出的新思路。以鸡西滴道矿立井为研究对象,利用地质动力区划方法确定不同尺度和级别构造运动的特征,建立板块构造学说与矿井工程实际的联系,将对矿井煤与瓦斯突出产生影响的因素为参数,采用多因素模式识别概率预测方法划分研究区域内的危险区域。研究表明该方法对煤与瓦斯突出区域预测的合理性与有效性,可以在实际工程中应用推广。 相似文献
75.
在珠江三角洲地区采集人、猪、牛、狗以及家禽等33个粪便样品,高效提取基因组DNA,选取14种特异性拟杆菌引物进行检验分析,并进一步采用已知污染源类型的水样对其进行验证.结果表明:采用粪便样品DNA专属提取试剂盒和水体样品DNA专属提取试剂盒提取的基因组模版纯度和提取率均符合后续实验要求.拟杆菌通用引物2#(Bac32F/Bac708R)检出率为85%(28/33),特别是对哺乳类动物和鸡的粪便具有更高的检出率.人的拟杆菌特异性引物3#(HF134F/ Bac708R)和4#(HF183F/Bac708R)、反刍动物的拟杆菌特异性引物8#(CF128F/Bac708R)以及猪的拟杆菌特异性引物10#(PF163F/Bac708R)在珠江三角洲地区同时具有较高的灵敏度和较强的特异性.水体样品验证实验与实际污染类型相符,说明拟杆菌通用引物2#、人的特异性引物3# 和4# 以及猪的特异性引物10# 在珠江三角洲地区具有很好的适用性. 相似文献
76.
基于景观结构和空间统计方法的绿洲区生态风险分析——以石羊河武威、民勤绿洲为例 总被引:1,自引:0,他引:1
论文以石羊河流域武威、民勤绿洲为研究区域,在ArcGIS 10.0、ArcView 3.2 软件和景观格局分析软件FRAGSTATS的技术支持下,采用干扰度指数、景观脆弱度指数、优势度指数和破碎度等指数,并通过分析景观格局与生态风险度之间的关系,将各景观指数进行栅格叠置运算,从而构建生态风险度,在此基础上,利用GIS局部空间统计方法研究分析了绿洲区景观结构格局和生态风险的时空变化特征及聚集模式。研究结果表明:① 城乡用地快速扩展的同时,耕地和草地景观有较大幅度的降低,优势景观类型由耕地、草地向耕地和建设用地转变;② 武威绿洲生态风险经历了从较高到中度的转变,生态风险整体趋于好转,而民勤绿洲生态风险从中/较高到较高/高变化,生态风险有所恶化;③ 武威绿洲主要为高于平均值的要素趋于聚集,表现为低生态风险小区高度聚集,且聚集度有上升的趋势,而民勤绿洲则主要为低于平均值的要素趋于聚集,高生态风险小区高度聚集,随着时间的推移呈现面积增大、空间扩展的态势。 相似文献
77.
78.
长江三角洲地区基于喷涂工艺的溶剂源VOCs排放特征 总被引:3,自引:6,他引:3
了解挥发性有机物(volatile organic compounds,VOCs)的溶剂源排放特征是制定长江三角洲地区PM2.5和臭氧防控策略的关键.本研究通过罐采样-GC-MS/FID测定了长江三角洲地区重点喷涂行业(集装箱喷涂、造船喷涂、木器喷涂和汽车喷涂业)的VOCs排放特征.结果表明,长江三角洲地区喷涂行业排放的主要VOCs组分为甲苯、二甲苯、乙苯等芳香烃类物质,三者之和占总VOCs的质量分数为79%~99%.生产工艺的不同对VOCs的排放组成影响并不大,废气处理装置中活性炭吸附对VOCs的组成并无明显影响,而催化燃烧的处理过程会使VOCs的排放组成产生显著变化,乙烯排放明显增大,同时也使得催化燃烧处理最大增量反应活性(maximum increment reactivity,MIR)值高于活性炭吸附处理后的MIR值,说明不同的处理措施的使用将影响VOCs对臭氧的生成作用. 相似文献
79.
A highly resolved temporal and spatial air pollutant emission inventory for the Pearl River Delta region, China and its uncertainty assessment 总被引:31,自引:0,他引:31
Junyu Zheng Lijun Zhang Wenwei Che Zhuoyun Zheng Shasha Yin 《Atmospheric environment (Oxford, England : 1994)》2009,43(32):5112-5122
A highly resolved temporal and spatial Pearl River Delta (PRD) regional emission inventory for the year 2006 was developed with the use of best available domestic emission factors and activity data. The inventory covers major emission sources in the region and a bottom–up approach was adopted to compile the inventory for those sources where possible. The results show that the estimates for SO2, NOx, CO, PM10, PM2.5 and VOC emissions in the PRD region for the year 2006 are 711.4 kt, 891.9 kt, 3840.6 kt, 418.4 kt, 204.6 kt, and 1180.1 kt, respectively. About 91.4% of SO2 emissions were from power plant and industrial sources, and 87.2% of NOx emissions were from power plant and mobile sources. The industrial, mobile and power plant sources are major contributors to PM10 and PM2.5 emissions, accounting for 97.7% of the total PM10 and 97.2% of PM2.5 emissions, respectively. Mobile, biogenic and VOC product-related sources are responsible for 90.5% of the total VOC emissions. The emissions are spatially allocated onto grid cells with a resolution of 3 km × 3 km, showing that anthropogenic air pollutant emissions are mainly distributed over PRD central-southern city cluster areas. The preliminary temporal profiles were established for the power plant, industrial and on-road mobile sources. There is relatively low uncertainty in SO2 emission estimates with a range of −16% to +21% from power plant sources, medium to high uncertainty for the NOx emissions, and high uncertainties in the VOC, PM2.5, PM10 and CO emissions. 相似文献
80.
Before climate change is considered in long-term coastal management, it is necessary to investigate how institutional stakeholders in coastal management conceptualize climate change, as their awareness will ultimately affect their actions. Using questionnaires in eight Baltic Sea riparian countries, this study examines environmental managers' awareness of climate change. Our results indicate that problems related to global warming are deemed secondary to short-term social and economic issues. Respondents agree that problems caused by global warming will become increasingly important, but pay little attention to adaptation and mitigation strategies. Current environmental problems are expected to continue to be urgent in the future. We conclude that an apparent gap exists between decision making, public concerns, and scientific consensus, resulting in a situation in which the latest evidence rarely influences commonly held opinions. 相似文献