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文章在论述地下水主要水化学特片的基础上,分析了地下水质酸性化的形成机理。认为研究区地下水质的酸性化主要发生于地下位季节变化带内,与岩体中黄铁矿的氧化作用密切相关;不同部位岩体中硫化含量的高低造成了产酸作用的差异,而后者则导致不同部位间地下水质的差异。所建的化学热力学模型模拟结果表明,在地下水质呈强酸化的部位,水-岩系间的相互作用具有较大的反应动力。对如何防治酸性水提出了建议。 相似文献
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本文借助于扫描电镜,对塔克拉玛干沙漠麻札塔格山地区石英砂表面微结构进行观察分析.并结合野外工作,推断沙物质的来源及形成环境,为沙漠研究提供微观依据. 相似文献
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Based on sediment and discharge flux data for the Yellow River, realistic forcing fields and bathymetry of the Bohai Sea, a suspended sediment transport module is driven by a wave-current coupled model to research seasonal variations and mechanisms of suspended load transport to the Bohai Sea. It could be concluded that surface sediment concentration indicates a distinct spatial distribution characteristic that varies seasonally in the Bohai Sea. Sediment concentration is rather high near the Yellow River estuary, seasonal variations of which are controlled by quantity of sediment from the Yellow River, suspended sediment concentration reaches its maximum during summer and fall. Furthermore, sediment concentration decreases rapidly in other seas far from the Yellow River estuary and maintains a very low level in the center of the Bohai Sea, and is dominated by seasonal variations of climatology wind field in the Bohai Sea. Only a small amount of sediments imported from the Yellow River are delivered northwestward to the southern coast of the Bohai Bay. Majority of sediments are transported southeastward to the Laizhou Bay, where sediments are continuously delivered into the center of the Bohai Sea in a northeastward direction, and part of them are transported eastward alongshore through the Bohai Strait. 69% of sediments from the Yellow River are deposited near the river delta, 31% conveyed seaward, within which, 4% exported to the northern Yellow Sea through the Bohai Strait. Wind wave is the most essential contributor to seasonal variations of sediment concentration in the Bohai Sea, and the contribution of tidal currents is also significant in shallow waters when wind speed is low. 相似文献
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Pedersenbreen冰川是我国北极冰川运动监测的重点研究区域之一。本文以2017年9月—2018年9月的共31景Sentinel-1A中等分辨率SAR影像数据为基础,采用PS-InSAR技术对Pedersenbreen冰川进行长时间序列的形变监测,获取Pedersenbreen冰川沿雷达视线方向的运动速率图,提取Pedersenbreen冰川沿雷达视线方向的运动信息。研究发现,Pedersenbreen冰川整体处于向下游运动的趋势,Pedersenbreen冰川主体的运动速率范围为-8.901~-2.957 m/a。将冰川运动速率沿铅垂线方向进行分解,得到GPS监测点P1、P2、P3、P4、P5缓冲区的冰川表面垂直变化速率均值,分别为-2.316 1 m/a、-2.438 7 m/a、-1.851 7 m/a、-2.181 1 m/a和-1.875 4 m/a。基于GPS实测数据进行处理,获得冰川表面垂直变化速率分别为-1.879 6 m/a、-2.041 3 m/a、-1.422 0 m/a、-1.722 3 m/a和-1.376 9 m/a,误差均在0.5 m/a之内,验证了结果的可靠性。表明PS-InSAR技术可以用于极地冰川运动趋势的变化监测,是冰川监测手段的一个有效补充。 相似文献
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Experimental Study on Formation Conditions of Ammoniojarosite and Its Environmental Significance 总被引:3,自引:0,他引:3
WANG Changqiu MA Shengfeng LU Anhuai ZHOU Jiangong 《《地质学报》英文版》2006,80(2):296-301
Formation conditions of ammoniojarosite in system Fe2(SO4)3-(NH4)2SO4-H2O are investigated in this paper. The results show that ammoniojarosite can be formed rapidly under normal temperature and pressure by controlling suitable pH value and Fe2(SO4)3 and (NH4)2SO4 concentrations. The pH value, temperature and concentration of Fe2(SO4)3 medium are key factors influencing the formation of ammoniojarosite. Under normal temperature, precipitation of ammoniojarosite can be seen within 24 hours at pH values between 2.6-3.1, and a great quantity of ammoniojarosite is formed within 48 hours. At about 90℃, the pH value range forming ammoniojarosite extends to 1.2-3.1, and within this range the rise of pH value is advantageous to the formation of ammoniojarosite and high Fe2(SO4)3 concentration is also advantageous. Relative pure ammoniojarosite is synthesized under high Fe2(SO4)3 concentration (≥0.05 M) and ammoniojarosite containing melanterite and colloid amorphous hydroxide vitriol iron is formed at low Fe2(SO4)3 concentration. The deposition process of ammoniojarosite can be used to harness wastewater from mines and other industries and remove S, Fe and other toxic and harmful elements, such as As, Cr, Hg, Pb in water. Rapid formation of ammoniojarosite and other jarosite analogs under normal temperature and pressure has a good potential prospect for harnessing acid wastewater by means of precipitation of jarosite and its analogs. 相似文献