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1.
Manolis N. Romanias Yangang Ren Benoit Grosselin Véronique Daële Abdelwahid Mellouki Pavla Dagsson-Waldhauserov Frederic Thevenet 《环境科学学报(英文版)》2020,32(9):155-164
The heterogeneous degradation of nitrogen dioxide (NO2) on five samples of natural Icelandic volcanic particles has been investigated. Laboratory experiments were carried out under simulated atmospheric conditions using a coated wall flow tube (CWFT). The CWFT reactor was coupled to a blue light nitrogen oxides analyzer (NOx analyzer), and a long path absorption photometer (LOPAP) to monitor in real time the concentrations of NO2, NO and HONO, respectively. Under dark and ambient relative humidity conditions, the steady state uptake coefficients of NO2 varied significantly between the volcanic samples probably due to differences in magma composition and morphological variation related with the density of surface OH groups. The irradiation of the surface with simulated sunlight enhanced the uptake coefficients by a factor of three indicating that photo-induced processes on the surface of the dust occur. Furthermore, the product yields of NO and HONO were determined under both dark and simulated sunlight conditions. The relative humidity was found to influence the distribution of gaseous products, promoting the formation of gaseous HONO. A detailed reaction mechanism is proposed that supports our experimental observations. Regarding the atmospheric implications, our results suggest that the NO2 degradation on volcanic particles and the corresponding formation of HONO is expected to be significant during volcanic dust storms or after a volcanic eruption. 相似文献
2.
Gabriele Fava Romeo Fratesi Maria Letizia Ruello Daniela Sani 《Chemistry and Ecology》2013,29(3-4):223-232
The present work relates to galvanized structures with several years of time life subjected to atmospheric corrosion, like galvanized high tension steel pylons. The mass and fate of zinc released is evaluated both via empirical and experimental procedures. The corrosion rate determination requested atmospheric condition characterization, especially for SO 2 concentration and experimental activities focused on soil sampling around pylons. The soil zinc content, total and exchangeable, is determinates by different analytical procedures. The zinc diffusion in environment and the zinc extension under the top soil is evaluated using 1-dimensional mathematical model for miscible species in porous soil. 相似文献
3.
板内火山喷发机制的研究 总被引:1,自引:2,他引:1
本文从地幔对流的观点出发,结合物理学中的涡旋定律及热爆炸理论,指出地幔对流涡旋中心摩擦生热导致的热爆炸导致氚,氚的热核反应炸裂涡旋中心上部地壳形成板内火山喷发,并利用美国Goddard宇航中心的卫星重力扰动位系数,反演了五大连火山地区的地幔对流图像,指出五大连池火山地区存在-地幔涡旋。 相似文献
4.
水上个体救生具是指随身携带、供个体使用的一种在紧急状况下可以提供浮力以使落水者漂浮在水面上的水上救生工具 ,具有安全漂浮、营救、适体和保暖等基本性能。水上个体救生具根据用途、结构和浮力材料的不同有不同的分类 ,同时材料性能优化、结构适体和属具集成是其发展趋向。 相似文献
5.
Ammonium and nitrate concentrations have been investigated in water samples from the wells in the island of Vulcano, (Italy). Systematic observations, extended over a period of five years, have verified different trends in the changing concentrations of both species. Nitrate ion is considered as contributed to the unconfined upper ground aquifer by the surface environment, while for ammonium ion a deep origin appears more likely. Significant changes in the activity of the volcanic system appear to affect the distribution of ammonium only, while nitrate levels do not display any important variation. 相似文献
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正镶白旗火山杂岩为一不规则的穹丘状地质体,它是由渐变过渡的火山碎屑岩、流纹质碎斑熔岩和次火山岩构成的一个整体.可初步划分出三个近似同心环带.中环的流纹质碎斑熔岩是火山杂岩的主体,它的众多特征反映出初始岩浆含有较多的挥发分.岩浆在地下经过了较好的结晶分异,在地下——地上某个范围内存在隐爆——侵出区.火山作用是以小规模隐爆伴随缓慢的向上侵出为主.作用时间长,形成了规模较大的火山岩.正镶白旗火山杂岩属太平洋岩系钙碱质系列,原始岩浆由来源于上地幔和下地壳熔体的混熔作用形成. 相似文献
8.
This paper presents the results of empirical research on Montserrat, in the British West Indies, undertaken in 2008–2010. It highlights the challenges of managing a crisis that evolved from acute to chronic over a period of fifteen years. In particular, the paper considers the evolution of science and policy over a period of fifteen years in its social and cultural context. It discusses the relationship between different types of evolving knowledges, and the interaction between them. Finally, a reflexive model is introduced to draw attention to some of the challenges of managing the science–policy interface under high uncertainty and high stakes. 相似文献
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本文阐明火山灾害是一种重大自然灾害,给人民生命财产造成严重损失。文中指出当前火山活动进入新的活跃期,提出我国火山灾害的潜在危险。我国许多休眠火山区,正在成为新的经济开发区和旅游疗养、开发地热和建材资源的新兴城镇,人口迅速增加,经济蓬勃发展。但还没有采取有效的火山监测研究和防灾措施。作者建议,应把火山监测研究纳入政府防灾日程,制定规划,拨出专款,把防御火山灾害同国土开发,经济建设结合起来。 相似文献
10.
Rainer W. Sieke Günter Lippke Alfred Krippendorf Rainer Haas Sven Lüdtke 《Environmental science and pollution research international》1998,5(4):199-201
The new technology of Plasmazon® uses the extremely strong oxidation of radicals to break up the compocunds of organic connections, e.g. chemical warfare agents like Clark I. In making a comparison of oxidation to normal ozone, the factor of the Plasmazon® -technology is available up to 103. The investigation in an experimental test shows that it is possible to destroy the warfare agent character of Clark I. As the possibility of a large-lot application this technology is the method of choice for other chemical or biological warfare agents. 相似文献