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通过一维砂柱实验研究了阴离子表面活性剂十二烷基苯磺酸钠(SDBS)对空气扰动技术(air sparging,AS)修复氯苯污染地下水的强化效果.结果表明,SDBS的加入降低了地下水的表面张力,减小了水气两相毛细压力,从而提高了地下水中的空气饱和度.当曝气量为100 mL/min,地下水的表面张力由72.2 mN/m降至49.5 mN/m时,地下水中空气饱和度由13.2%提高至50.1%,而后随着表面张力的进一步降低,空气饱和度不再提高,反而有小幅下降.通过污染物的去除实验发现,SDBS的加入大大提高了氯苯的去除率,且去除率的变化与空气饱和度的变化趋势基本相符.因此,表面活性剂的加入可以作为空气扰动技术一种十分有效的强化手段. 相似文献
146.
Ridge subduction and porphyry copper-gold mineralization:An overview 总被引:35,自引:0,他引:35
SUN WeiDong LING MingXing YANG XiaoYong FAN WeiMing DING Xing & LIANG HuaYing CAS Key Laboratory of Isotope Geochronology Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China Research Center for Mineral Resources School of Earth Space Sciences University of Science Technology of China Hefei Graduate University of Chinese Academy of Sciences Beijing Key Laboratory for Metallogenic Dynamics ... 《中国科学:地球科学(英文版)》2010,(4)
Many large porphyry Cu-Au deposits are connected to adakitic rocks known to be closely associated with ridge subduction. For example, there are several subducting ridges along the east Pacific margin, e.g., in Chile, Peru, and South America, most of which are associated with large porphyry Cu-Au deposits. In contrast, there are much fewer ridge subductions on the west Pacific margin and porphyry Cu-Au deposits are much less there, both in terms of tonnage and the number of deposits. Given that Cu and Au are... 相似文献
147.
DENG Hao ZHANG LiQiang MAO XianCheng MA JingTao KANG ZhiZhong PENG JunHuan RUI XiaoPing & LIU Liu State Key Laboratory of Remote Sensing Science Beijing Normal University Beijing China School of Geoscience Environmental Engineering Central South University Changsha PTV America Inc. Broadway Plaza Ste Tacoma WA USA 《中国科学:地球科学(英文版)》2010,(1)
In the application of 3D Geoscience Modeling,we often need to generate the volumetric representations of geological bodies from their surface representations.Linear octree,as an efficient and easily operated volumetric model,is widely used in 3D Geoscience Modeling.This paper proposes an algorithm for fast and dynamic generation of linear octrees of geological bodies from their surface models under hardware acceleration.The Z-buffers are used to determine the attributes of octants and voxels in a fast way,a... 相似文献
148.
Conductivity structure and rheological property of lithosphere in Southern Tibet inferred from super-broadband magnetotelluric sounding 总被引:2,自引:0,他引:2
To understand deep lithosphere structure beneath the Qinghai-Tibet Plateau more comprehensively and objectively and to explore important scientific issues,such as characteristics of plateau lithospheric deformation,state of strain,thermal structure,plate (or terrane) movement,and crust-mantle rheology,it is necessary to research the variation of crust-mantle electrical structure in the east-west direction in every geological unit.For this purpose,six super-broadband magnetotelluric (MT) sounding profiles ha... 相似文献
149.
Climate variability recorded by n-alkanes of paleolake sediment in Qaidam Basin on the northeast Tibetan Plateau in late MIS3 总被引:1,自引:0,他引:1
PU Yang ZHANG HuCai LEI GuoLiang CHANG FengQin YANG MingSheng ZHANG WenXiang LEI YanBin YANG LunQing & PANG YouZhi State Key Laboratory of Lake Science Environment Nanjing Institute of Geography Limnology Chinese Academy of Sciences Nanjing China Graduate University of Chinese Academy of Sciences Beijing Key Laboratory of Boyang Lake MOE School of Environmental Chemical Engineering Nanchang University Nanchang 《中国科学:地球科学(英文版)》2010,(6)
Here we combine n-alkanes preserved in a shell bar section from Qarhan paleolake, Qaidam Basin with the other sedimentary proxies to elucidate the lake evolution process during the period 39.7 to 17.5 14C ka BP (calibrated age ranges from 43.5 to 22.4 cal. ka BP). In different stages, the n-alkane homologues exhibited different distribution modes indicative of variations in the surrounding vegetation and the hydrologic condition of the lake. The n-alkanes proxies (CPIh, ACLh, Paq) have the same trends as th... 相似文献
150.