This study is primarily focused on Cleveland-Akron-Lorain nonattainment area in northeastern Ohio. The base year 2002 considered in this study witnessed one of the worst cases of ozone pollution in this region with oz...This study is primarily focused on Cleveland-Akron-Lorain nonattainment area in northeastern Ohio. The base year 2002 considered in this study witnessed one of the worst cases of ozone pollution in this region with ozone values exceeding previous 8-hour ozone standards of 84 ppb. The photochemical modeling system CAMx was applied to compute relative reduction factors, which were used subsequently to scale the base year (2002) values at the ozone monitoring sites to estimate the ozone design values for the year 2009 in Cleveland area for different emissions reduction scenarios. The results disclose that the largest change in the 2009 ozone design values consequent to applying auxiliary emission control strategies is between 1 and 1.5 ppb, which still left certain counties in northeastern Ohio unable to demonstrate attainment. The results are important in the development of emission control strategies in today’s context with instillation of even more stringent ozone standards and potential future increases in ozone concentrations due to climate change.展开更多
Proterozoic rocks in the northeastern Jiangxi-southern Anhui may fall into three rock associations whichbelong to different but interrelated tectono-palaeogeographic units. The field geological and petrochemicalcharac...Proterozoic rocks in the northeastern Jiangxi-southern Anhui may fall into three rock associations whichbelong to different but interrelated tectono-palaeogeographic units. The field geological and petrochemicalcharacteristics of the northeastern Jiangxi-western Zhejiang volcanic zone indicate that it was once an islandarc zone. An analysis of the sedimentary characteristics of Proterozoic turbidites lying north of the zone has re-vealed the history of development of a back-arc basin. According to the type of the Proterozoic rock formationsouth of the zone, it may be deduced that the formation might represent the fore-arc and trench areas. Bymeans of various tectono-palaeogeographic analyses, the relation between the island arc zone and the back-arcbasin is inferred and the Late Proterozoic tectono-palaeogeographic development is discussed by using themodel of the trench-arc-basin system.展开更多
[目的]直观把握东北黑土区沟蚀研究进展与热点,推进东北黑土区沟蚀研究领域的发展。[方法]以CNKI与Web of Siencec数据库中245篇相关文献为对象,利用文献计量的方法,使用CiteSacep软件绘制东北黑土区沟蚀研究知识图谱。[结果]结果表明:...[目的]直观把握东北黑土区沟蚀研究进展与热点,推进东北黑土区沟蚀研究领域的发展。[方法]以CNKI与Web of Siencec数据库中245篇相关文献为对象,利用文献计量的方法,使用CiteSacep软件绘制东北黑土区沟蚀研究知识图谱。[结果]结果表明:(1)黑土区沟蚀研究起步较晚,近十年发文量显著增加,但国际期刊发表成果较少,仅占26%。(2)该领域研究力量主要分布在我国东北,其中水利部松辽流域委员会、北京师范大学、中国科学院东北地理与农业生态研究所、东北农业大学、沈阳农业大学等机构贡献突出、影响较大;张树文是该领域中文发文量最多的学者,刘宝元和伍永秋是英文发文量最多的学者。(3)关键词共现表明,目前对东北黑土区沟蚀的关注重点主要集中在侵蚀沟发育特征、影响因素和沟蚀防治措施等方面。[结论]东北黑土区沟蚀尚未形成完整的研究框架和全面的认识,在未来的研究中,需进一步注重东北黑土区沟蚀形成和发育过程及机理研究,并深入分析地质、地形、水文、人类活动等因素的影响。展开更多
文摘This study is primarily focused on Cleveland-Akron-Lorain nonattainment area in northeastern Ohio. The base year 2002 considered in this study witnessed one of the worst cases of ozone pollution in this region with ozone values exceeding previous 8-hour ozone standards of 84 ppb. The photochemical modeling system CAMx was applied to compute relative reduction factors, which were used subsequently to scale the base year (2002) values at the ozone monitoring sites to estimate the ozone design values for the year 2009 in Cleveland area for different emissions reduction scenarios. The results disclose that the largest change in the 2009 ozone design values consequent to applying auxiliary emission control strategies is between 1 and 1.5 ppb, which still left certain counties in northeastern Ohio unable to demonstrate attainment. The results are important in the development of emission control strategies in today’s context with instillation of even more stringent ozone standards and potential future increases in ozone concentrations due to climate change.
文摘Proterozoic rocks in the northeastern Jiangxi-southern Anhui may fall into three rock associations whichbelong to different but interrelated tectono-palaeogeographic units. The field geological and petrochemicalcharacteristics of the northeastern Jiangxi-western Zhejiang volcanic zone indicate that it was once an islandarc zone. An analysis of the sedimentary characteristics of Proterozoic turbidites lying north of the zone has re-vealed the history of development of a back-arc basin. According to the type of the Proterozoic rock formationsouth of the zone, it may be deduced that the formation might represent the fore-arc and trench areas. Bymeans of various tectono-palaeogeographic analyses, the relation between the island arc zone and the back-arcbasin is inferred and the Late Proterozoic tectono-palaeogeographic development is discussed by using themodel of the trench-arc-basin system.
文摘[目的]直观把握东北黑土区沟蚀研究进展与热点,推进东北黑土区沟蚀研究领域的发展。[方法]以CNKI与Web of Siencec数据库中245篇相关文献为对象,利用文献计量的方法,使用CiteSacep软件绘制东北黑土区沟蚀研究知识图谱。[结果]结果表明:(1)黑土区沟蚀研究起步较晚,近十年发文量显著增加,但国际期刊发表成果较少,仅占26%。(2)该领域研究力量主要分布在我国东北,其中水利部松辽流域委员会、北京师范大学、中国科学院东北地理与农业生态研究所、东北农业大学、沈阳农业大学等机构贡献突出、影响较大;张树文是该领域中文发文量最多的学者,刘宝元和伍永秋是英文发文量最多的学者。(3)关键词共现表明,目前对东北黑土区沟蚀的关注重点主要集中在侵蚀沟发育特征、影响因素和沟蚀防治措施等方面。[结论]东北黑土区沟蚀尚未形成完整的研究框架和全面的认识,在未来的研究中,需进一步注重东北黑土区沟蚀形成和发育过程及机理研究,并深入分析地质、地形、水文、人类活动等因素的影响。
