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黑碳气溶胶由于其对大气辐射平衡和气候的影响而受到高度重视,碘化学则是大气化学中十分重要的研究领域。然而对于卤素化合物尤其含碘化合物与黑碳气溶胶表面相互作用的研究还少有报道。文中首次研究了在298K下,碘氧自由基(IO)重要源之一的碘代异丙烷(i-C3H7I)在黑碳表面的吸附,黑碳样品使用DegussaFW2(一种含有氧化态的无定形黑碳)。实验发现碘代异丙烷与黑碳表面发生相互作用,使黑碳表面逐渐被钝化,并且其吸附系数(γ)与暴露时间相关。实验测得初始吸附系数(γ0)值为(9.5±3.8)×10-2。所报道的初始吸附系数γ0可以提供一个上限值,实验结果表明在真实大气环境下,i-C3H7I在黑碳气溶胶表面的非均相消耗可能是十分重要的,也许会对i-C3H7I在真实大气中的浓度有一定影响。并且研究结果对进一步研究i-C3H7I与黑碳气溶胶相互作用对大气辐射平衡、黑碳气溶胶非均相化学作用和云雾降水凝结核(CCN)形成的影响均有十分重要的意义,研究结果也为评估i-C3H7I与碳质气溶胶非均相相互作用对大气环境的影响和深入的模式研究提供了基本参数。 相似文献
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二次光化学氧化剂与气溶胶间的非均相过程 总被引：5，自引：0，他引：5
光氧化剂和气溶胶颗粒物在大气环境中普遍存在,影响着大气氧化能力和气候,威胁着人类健康。而大气光氧化剂与气溶胶颗粒物间复杂的耦合相互作用能产生二次污染物,使得大气污染过程更为复杂,成为国际大气化学研究的前沿和热点课题。挥发性有机物（VOCs）和氮氧化物（NOx）等一次污染物在大气中经过复杂的光化学反应可形成以臭氧（O3）为主的二次光化学氧化剂,并以大气气溶胶为平台发生非均相反应,使大气污染更严重,引起人们普遍关注。二次光化学氧化剂和气溶胶颗粒物之间非均相过程的实验室研究是深入认识这两者间耦合相互作用的关键,实验室研究可以为分析和深入认识外场观测结果提供基础,还能为数值模式模拟研究提供基本参数。概括了大气二次光化学氧化剂的形成过程,总结了国际上近年来二次光化学氧化剂与大气气溶胶颗粒物非均相反应的实验室研究进展以及研究方法,最后提出了现有的一些主要科学问题,对未来这一重要领域的研究前景进行了展望。 相似文献
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Anthropogenic emissions alter biogenic secondary organic aerosol(SOA) formation from naturally emitted volatile organic compounds(BVOCs). We review the major laboratory and field findings with regard to effects of anthropogenic pollutants(NOx, anthropogenic aerosols, SO_2, NH_3) on biogenic SOA formation. NOx participate in BVOC oxidation through changing the radical chemistry and oxidation capacity, leading to a complex SOA composition and yield sensitivity towards NOx level for different or even specific hydrocarbon precursors. Anthropogenic aerosols act as an important intermedium for gas–particle partitioning and particle-phase reactions, processes of which are influenced by the particle phase state, acidity, water content and thus associated with biogenic SOA mass accumulation. SO_2 modifies biogenic SOA formation mainly through sulfuric acid formation and accompanies new particle formation and acid-catalyzed heterogeneous reactions. Some new SO_2-involved mechanisms for organosulfate formation have also been proposed.NH_3/amines, as the most prevalent base species in the atmosphere, influence biogenic SOA composition and modify the optical properties of SOA. The response of SOA formation behavior to these anthropogenic pollutants varies among different BVOCs precursors. Investigations on anthropogenic–biogenic interactions in some areas of China that are simultaneously influenced by anthropogenic and biogenic emissions are summarized. Based on this review, some recommendations are made for a more accurate assessment of controllable biogenic SOA formation and its contribution to the total SOA budget. This study also highlights the importance of controlling anthropogenic pollutant emissions with effective pollutant mitigation policies to reduce regional and global biogenic SOA formation. 相似文献
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Wang Tijian Gao Taichang Zhang Hongsheng Ge Maofa Lei Hengchi Zhang Peichang Zhang Peng Lu Chunsong Liu Chao Zhang Hua Zhang Qiang Liao Hong Kan Haidong Feng Zhaozhong Zhang Yijun Qie Xiushu Cai Xuhui Li Mengmeng Liu Lei Tong Shengrui 《中国科学:地球科学(英文版)》2019,62(12):1903-1945
Since the founding of the People's Republic of China 70 years ago,the subject of atmospheric physics and atmospheric environment has developed rapidly in China,providing important support for the development of atmospheric science and guarantee for the development of national economy.In this paper,the general advancement of atmospheric physics and atmospheric environment in last 70 years was described.The main research progress of atmospheric physics and atmospheric environment in the past 40 years of reform and opening-up was reviewed,the outstanding research achievements since the 21 st century were summarized,the major problems and challenges are pointed out,and the key directions and suggestions for future development are put forward. 相似文献
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现代地震观测积累了大量、种类繁多的地震前兆数据和震后数据,但数据中隐含的地震规律及趋势无法用经典的算例、数学公式、物理公式进行定量解释、分析和预测,需要探索新方法、新技术。案例表明,大数据分析具有预测事物发展趋势、改变传统观念和发现新事物的功能,有助于从错误信息中挖掘有价值信息。本文由此提出基于大数据技术处理地震数据的新思路,对地震监测预报新思路进行探索;通过在大数据平台上基于地震目录的余震预测研究,给出大数据技术在地震数据处理方面的一个应用实例,验证该思路的可行性。 相似文献
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