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421.
Hongxia Liu Kimitaka Kawamura Bhagawati Kunwar Junji Cao Jiaquan Zhang Changlin Zhan 《Journal of the Air & Waste Management Association (1995)》2019,69(4):513-526
PM2.5 (particulate matter with an aerodynamic diameter <2.5 μm) samples were collected in Huangshi, central China, from March 2012 to February 2013 and were analyzed for dicarboxylic acids (diacids) and related compounds (DARCs). Oxalic acid (C2; 416 ng m?3) was the most abundant species, followed by phthalic (Ph; 122 ng m?3), terephthalic (tPh; 116 ng m?3), succinic (C4; 70.4 ng m?3), azelaic (C9; 67.9 ng m?3), and adipic (C6; 57.8 ng m?3) acids. Relatively high abundances of Ph and tPh differed from the distribution in urban and marine aerosols, indicating contributions from nearby anthropogenic sources. Glyoxylic acid (ωC2; 41.4 ng m?3) was the dominant oxoacid, followed by 9-oxononanoic (ωC9; 40.8 ng m?3) and pyruvic (Pyr; 24.1 ng m?3) acids. Glyoxal (Gly; 35.5 ng m?3) was the dominant α-dicarbonyl. Highest average concentrations were found for C2, ωC2, and C9 in autumn, for C4, for Pyr and C6 in spring, for Ph, ωC9, and Gly in summer, whereas the lowest values were observed in winter. Seasonal variations and correlation coefficients of DARCs demonstrate that both primary emissions and secondary production are important sources. Principal component analysis of selected DARCs species suggests that a mixing of air masses from anthropogenic and biogenic sources contribute to the Huangshi aerosols.
Implications: Both primary emissions and secondary production are important sources of diacids and related compounds in PM2.5 from Huangshi, central China. Principal component analysis of selected diacids in Huangshi aerosols suggests that mixing of air masses from anthropogenic and biogenic sources contribute to ambient aerosols in central China. 相似文献
422.
Ni Qingjian Cao Xuehan Tan Chaoqun Peng Wenqiang Kang Xuying 《Environmental science and pollution research international》2023,30(5):11516-11529
Environmental Science and Pollution Research - The analysis and prediction of water quality are of great significance to water quality management and pollution control. In general, current water... 相似文献
423.
Zhijian Liu Haiyang Liu Hang Yin Rui Rong Guoqing Cao Qihong Deng 《Frontiers of Environmental Science & Engineering》2021,15(3):36
424.
Guyuan Luo Faping Bu Xiaoyi Xu Jia Cao Weiqun Shu 《Environmental monitoring and assessment》2011,173(1-4):55-64
Field surveys were carried out from January 2007 to December 2008 to investigate seasonal variations of dissolved inorganic nitrogen (DIN) and phosphorus (DIP) transported to the Linjiang Bay of the Three Gorges Reservoir, China. The results revealed that both DIN and DIP exhibited large seasonal variability. DIN (dominated by NH4?CN) concentrations were drastically higher in the dry season than those in the rainy season, and the same seasonal patterns of DIP concentrations and DIN and DIP fluxes were observed but inverse to that of DIN concentrations. The interannual variation in DIN fluxes descended by 28.2% from 2007 to 2008, while DIP fluxes increased by 40.9%, which were closely constant with interannual changes in DIN and DIP concentrations, respectively. The study indicated that nutrient fluxes (DIN and DIP) were strongly correlated with both nutrient concentrations and river discharge, and the Linjiang Bay received approximately 3,416 × 103 kg DIN and 324 × 103 kg DIP every year. In addition, DIN mainly originated from point sources, but DIP originated from non-point sources. It is shown that to control point source pollution is the most effective step for water quality improvement and reducing nutrient loading inputs in the Linjiang Bay. 相似文献
425.
湖南省宁乡县巷子口—沩山荒漠化治理研究 总被引:1,自引:0,他引:1
曹学章 《生态与农村环境学报》1998,(1)
巷子口—沩山地处我国南方红壤丘陵地区。由于长期过度砍伐和陡坡开垦等不合理人为活动的影响,加上降雨多且暴雨集中、丘陵地形和花岗岩母质的自然条件,这里由水蚀导致的荒漠化一度比较严重,1982年以来,采取封禁与造林相结合恢复植被、多途径解决农村能源问题、坡耕地退耕还林、广泛开展宣传、加强机构建设、落实政策、加强监督等措施,开展了荒漠化治理,取得了显著的生态和经济效益。 相似文献
426.
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428.
我国铁路水害频发且损失巨大,如何有效防范,已成业界难题,更为运营部门汛期工作重点。但铁路水害泛指由降水或其他水源造成断道、限速事故的灾害,预测预报缺乏针对性。鉴于此,首先,借鉴水利学水害概念,丰富了铁路水害的机理内涵,再结合铁路调研,明确了预测目标的外延;其次,基于京广线湖(南)广(东)区段水害气象、地质与设施条件统计,分析了铁路水害的时空分布特征,建立了致灾因子指标体系;最后,针对降水这一关键诱发因子,筛选出1 h与日降雨量两个相关性最强的计算参数,建立了logistic概率预测模型。模型检验表明:其统计学检验通过,且对于灾害实际情况预测效果较好,可为铁路水害风险管理及防范措施的制定提供参考。 相似文献
429.
曹敏 《安全.健康和环境》2015,15(4):31-34
某油田在钻探过程中成功应用济南柴油机厂3000系列天然气发动机,代替原有的柴油发动机进行各阶段的钻井作业,实践证明天然气发动机不但动力性、响应性不亚于柴油机,而且达到了降低生产成本、减少污染排放、营造健康舒适的工作环境的目的,是一项值得在钻井生产中推广应用的清洁生产实用技术. 相似文献
430.