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随着丹东地区经济的快速发展,丹东地区渔船、游船、货船的船舶数量也随着增加,而船舶污染也随之严重起来。报告了丹东港口船舶污染问题的现状,对船舶不正当排放的污染源及船舶污染的特点进行调查,最后对船舶污染的治理提出建议。 相似文献
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Chorng-Shern Horng Chih-An Huh Kuo-Hang Chen Pin-Ru Huang Kan-Hsi Hsiung Hui-Ling Lin 《Journal of Marine Systems》2009,76(4):468
Kaohsiung City and its neighborhood in the southwestern coastal plain of Taiwan have suffered serious air pollution since the region became the largest center for heavy-industry on the island. In order to unravel the air pollution history of the region, four 210Pb- and 137Cs-dated sediment box cores recovered in 2006 from offshore of this area were chosen for magnetic and petrographic analyses. The data were used to distinguish changes in concentration, composition and grain size of magnetic particles in the sediments due to inputs of anthropogenic magnetic spherules. Sedimentation rates have been reasonably constant for the last one hundred years, except at the core tops which were affected by a turbidite layer induced by a typhoon in 2005. Down-core profiles of mass-specific magnetic susceptibility (χ) and saturation isothermal remanent magnetization (SIRM) are similar among the cores, and reflect similar trends to magnetic spherule counts. This reveals that χ and SIRM of modern marine sediments can be used as air pollution indicators for nearby industrialized upwind areas. The studied record indicates that industrialization of the area was gradual during 1950–1980 and boomed afterward, resulting in a high production of airborne magnetic spherules, which is consistent with evidence for poor air quality at that time. Optical and scanning electron microscopic (SEM) surveys of magnetic extracts indicate that the magnetic spherules have grain sizes ranging from a few micrometers up to 50 μm and consist mainly of iron oxides with variable Si, Al, and Ca contents. X-ray diffraction analysis on magnetic extracts from different depths in the cores further indicates that magnetite and pyrrhotite, which are derived from terrigenous detritus, form the magnetic constituents of the sediments before the area was industrialized. In contrast, during the industrial boom, anthropogenic magnetite and hematite spherules became the dominant magnetic particles in the sediments. Down-core profiles of hard isothermal remanent magnetization (HIRM) below the turbidite layer also reveal similar trends to the corresponding magnetic spherule counts, which indicate that the concentration of hematite in the sediments is also closely related to the extent of air pollution. In addition, relatively low values of χARM/χ, which are indicative of coarse magnetic grains, started to occur when large magnetite spherules became significant during the industrialized period. The air pollution history elucidated from our sediment core data not only reflects the development of Kaohsiung from a small village to a highly industrialized metropolitan area in the 20th century, but it is also consistent with the most recent air pollution trends revealed by real time air quality measurements of PM10. Our results demonstrate the usefulness of magnetic parameters for delineating the air pollution history of coastal marine sediments down-wind of nearby industrialized regions. 相似文献
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无谐波异步电动机软启动器的设计 总被引:1,自引:0,他引:1
文章介绍了一种以AT89C51单片机为主控核心器件,运用双向可控硅过零触发的PWM技术,实现异步电动机电源的调压控制的软起动器,它既可达到软起动器控制电动机起动电流的目的,又克服了一般软起动器易产生谐波污染的缺陷,有一定的实用推广价值。 相似文献
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王超 《辽宁省交通高等专科学校学报》2005,7(4):16-17
本文对高速公路噪声污染源进行了分析,并对高速公路声屏障的设计流程、减噪目标、结构形式、建造要求等进行了系统地阐述. 相似文献
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童梅 《青岛远洋船员学院学报》2005,26(3):29-32
国际油污赔偿机制下对可予赔偿的“环境损害”是明确的。我国对船舶溢油污染损害的民事赔偿在《民法通则》、《海商法》、《环境保护法》、《海洋环境保护法》中都包含了相关方面的法律规定。结合国内外法律规定,依据平等、国际公约优先、与国际接轨等原则,我国船舶溢油事故中海洋环境损害的赔偿范围应限定在《1992责任公约》所限定的“实际已采取或行将采取的合理复原措施的费用”。 相似文献
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兰州市大气污染成因分析 总被引:4,自引:0,他引:4
以兰州市大气污染为研究对象,针对兰州市区特殊情况,分别从气象条件和地形地貌,工业污染源,交通污染源和采暖污染源,沙尘暴和浮尘天气,地域发展不平衡等方面阐明影响兰州市大气污染的主要原因. 相似文献
30.
俞兴东 《重庆交通学院学报》2006,25(6):150-154
通过对三峡库区水污染严重性的综述,说明水资源总量控制的重要性和综合防治水污染的紧迫性.对人们自觉的改变用水习惯,增强节水减污意识,保护自然资源,优化生态环境,建设节约型社会,循环经济的实施,保持国民经济的可持续发展有着重要的现实意义.此外,笔者还提出了改善库区水污染的若干建议和具体措施. 相似文献