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991.
992.
To evaluate contamination caused by petroleum, surface soil samples were collected from both upland and paddy fields along the irrigation canals in the Hunpu wastewater irrigation region in northeast China. N-alkanes, terpanes, steranes, and phospholipid fatty acids (PLFA) in the surface soil samples were analyzed. The aliphatic hydrocarbon concentration was highest in the samples obtained from the upland field near an operational oil well; it was lowest at I-3P where wastewater irrigation promoted the downward movement of hydrocarbons. The Hunpu region was found contaminated by heavy petroleum from oxic lacustrine fresh water or marine deltaic source rocks. Geochemical parameters also indicated significantly heavier contamination and degradation in the upland fields compared with the paddy fields. Principal component analysis based on PLFA showed various microbial communities between petroleum contaminated upland and paddy fields. Gram-negative bacteria indicated by 15:0, 3OH 12:0, and 16:1(9) were significantly higher in the paddy fields, whereas Gram-positive bacteria indicated by i16:0 and 18:1(9)c were significantly higher in the upland fields (p < 0.05). These PLFAs were related to petroleum contamination. Poly-unsaturated PLFA (18:2ωup6, 9; indicative of hydrocarbon-degrading bacteria and fungi) was also significantly elevated in the upland fields. This paper recommends more sensitive indicators of contamination and degradation of petroleum in soil. The results also provide guidelines on soil pollution control and remediation in the Hunpu region and other similar regions. 相似文献
993.
全球变化及其相关的适应性研究是当前地学领域研究的焦点问题之一。在综述国内外相关研究成果的基础上,辨析全球变化、适应性等相关概念,梳理适应性研究的发展进程和侧重点,将其归纳为依附脆弱性研究和独立研究两大类。其中,依附脆弱性研究将脆弱性看作是适应能力的函数,研究主要集中在脆弱性评价下的适应指数研究、影响子因素分层研究与策略研究等几大部分;而独立适应性研究,通过构建完整的体系,研究集中在以指标评价法为代表的适应能力研究和以情景模拟法为代表的适应策略预测分析上。地学研究强调适应性的尺度问题,未来需加强对不同尺度规模适应性研究的定量分析,建立跨尺度适应性研究框架;深入研究城市适应全球变化的能力与策略;同时加强适应性研究相关技术和工具的开发,以提高适应能力评估的准确性及适应策略的科学性。 相似文献
994.
Chien-Chung Chen Tzu-Chi Wang Lu-Yen Chen Jie-Huei Dai Chi-Min Shu 《Journal of Loss Prevention in the Process Industries》2010,23(4):531-538
Industrial safety has noticeably improved in recent years in Taiwan. Despite these improvements, however, serious accidents including explosions, chemical releases, and fires have still occurred in companies such as the Fu Guo Chemical Company (2001), Sin Hun Chemical Company (2005), Motech Industries, Inc. (2005) and Nanpao Resin Co. (2010). These accidents resulted in great loss of life and property, and further caused demands for improvement. Chemical disasters usually result from the combination of several mistakes or gross carelessness and are seldom caused by a single episode. To ensure the safety of operating, handling and storing chemicals, as well as to prevent chemical disasters, one must take many critical points into account, such as techniques, manufacturing processes, operators, chemicals, and emergency response. In Taiwan, the hazards and risks of high-tech companies are higher than in other industrial sectors. Therefore, a variety of safety management methods and regulations appropriate for high-tech companies have been generated. We studied the current status of the indigenous loss prevention protocols based on the safety management of petrochemical and chemical-process high-tech industries in Taiwan. 相似文献
995.
于爽 《中国个体防护装备》2010,(3):49-49
<正>在高气温或同时存在高温热源的环境下进行的生产劳动,通称为高温作业。高温环境容易影响人体的生理及心理状态,在这种环境下工作,除了会影响工作效率外,更会引发各种意外和危机。高 相似文献
996.
997.
998.
研究了2,4,6-三氯酚(TCP)在水中不同存在形态、水体pH值、溶解氧、藻类对其光化学降解行为的影响。先用孔雀绿无色氰化物(MGLC),计算天津海河、北排污河两个自然水体,底泥悬浮物引起的光分散衰减系数,再用RG.Zeep公式预测出天津海河水中TCP的光解速率高于天津北排污河。天津污水土地处理系统进口水中TCP的光解速率常数:在夏季,kd=0.059(h-1);在冬季kd=0.011(b-1);光解半衰期为19.8h-1。实验结果为处理后污水的安全回用提供了科学依据。 相似文献
999.
1000.