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Firstly, the macroscopic chemical equilibrium state of a series of chemical reactions between intercrystal brine and its media salt layer (salt deposit) in Qarhan Salt Lake was studied by using the Pitzer theory. The concept of macroscopic solubility product and its relation with accumulated ore dissolving ratio were presented, which are used in the numerical model of dissolving and driving exploitation of potassium salt in Qarhan Salt Lake. And secondly, with a model forming idea oftransport model for reacting solutes in the multi-component fresh groundwater system in porous media being a reference, a two-dimensional transport model coupled with a series of chemical reactions in a multi-component brine porous system (salt deposits) was developed by using the Pitzer theory.Meanwhile, the model was applied to model potassium/magnesium transport in Qarhan Salt Lake in order to study the transfer law of solid and liquid phases in the dissolving and driving process and to design the optimal injection/abstraction strategy for dissolving and capturing maximum Potassium/Magnesium in the mining of salt deposits in Qarhan Salt Lake. 相似文献
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利用卫星测高资料推求西北太平洋海域的海洋大地水准面 总被引:3,自引:0,他引:3
本文根据卫星测高数据和海面动力地形资料,绘制了不相上下北太平洋海域局部大地水准面的精细结构图,对解决卫星测高技术中大地水准面积和海面地形的可分性问题作了初步尝试。 相似文献
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Genetic modification is useful for improving the nutritional qualities of cyanobacteria. To increase the total unsaturated fatty acid content, along with the ratio of ω-3/ω-6 fatty acids, genetic engineering can be used to modify fatty acid metabolism. Synechococcus sp. PCC7002, a fast-growing cyanobacterium, does not contain a Δ6 desaturase gene and is therefore unable to synthesize γ-linolenic acid (GLA) and stearidonic acid (SDA), which are important in human health. In this work, we constructed recombinant vectors Syd6D, Syd15D and Syd6Dd15D to express the Δ15 desaturase and Δ6 desaturase genes from Synechocystis PCC6803 in Synechococcus sp. PCC7002, with the aim of expressing polyunsaturated fatty acids. Overexpression of the Δ15 desaturase gene in Synechococcus resulted in 5.4 times greater accumulation of α-linolenic acid compared with the wild-type while Δ6 desaturase gene expression produced both GLA and SDA. Co-expression of the two genes resulted in low-level accumulation of GLA but much larger amounts of SDA, accounting for as much to 11.64% of the total fatty acid content. 相似文献
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痕量价态金的载炭泡塑吸附分离研究 总被引:2,自引:1,他引:2
研究了载炭泡塑对不同价态金的吸附选择性。当HCl溶液浓度1%-10%时,载炭泡塑对纳克量Au(Ⅲ)吸附率为96.3%-96.8%,而对Au(Ⅰ),Au(0)不产生吸附,分别在溶液和残渣中的Au(Ⅰ)和Au(0)经过滤分离,用王水处理后,由载炭泡塑分别吸附,其回收率分别为96.5%和98.9%。 相似文献
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黄河李家峡典型岩坡变形破坏的水效应研究 总被引:5,自引:0,他引:5
黄河上游李家峡段高陡岩坡变形破坏受多种因素控制, 其中水的影响十分明显, 主要包括水的静态效应和动态效应两方面。本文从地下水的软化作用、库岸水压力或静水压力、孔隙水压力, 以及河流冲蚀、边岸再造、降雨引起的动水压力作用和水库泄水引起的动水压力作用等方面, 结合数值模拟手段分别研究了它们对岩坡变形破坏的影响程度和方式。 相似文献
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Ling Zan Zhihuan Zhang Jiajia Fei Yuyuan Wu Zhenying Zhang Liming Qin Ling Mei Wenhao Li 《中国地球化学学报》2011,30(2):255-263
Through natural gas exploration in the Changling Fault Depression,abundant natural gas flows were obtained and high-quality source rocks were also reveiled.Based on bulk analyses,organic matter abundance,organic matter type and thermal maturity of the source rocks were studied systematically.At the same time,gas gener-ating intensity and gas generating quantity were quantitatively analyzed by using basin modeling technologies.The results indicated that gas source rocks of the Shahezi Formation are characterized by abundant organic matter and dark mudstone distributions and high-over thermal maturity.They possess high gas generating intensity with the biggest value surpassing 500×108 m3/km2,and large gas generating quantity,accounting from 74.40% of the total amount.The Yingcheng Formation has good gas-source rocks with moderate dark mudstone and relatively high organic matter.It has type-Ⅲ organic matter and low-over thermal maturity.The gas generating intensity is moderate,between 20×108 and 60×108 m3/km2.The gas generating quantity is 13.63% of the total amount.The Huoshiling Formation has relatively good source rocks with limited dark mudstone and low organic matter.It has type-Ⅲ kerogen and over-thermal maturity.The gas generating quantity is 7.10% of the total amount.The Denglouku Formation has poor-gas source rocks,and is characterized by undeveloped dark mudstone and low organic matter abundance.It has type-Ⅲ organic matter and low-high thermal maturity.Hydrocarbon gases in the Changling Fault Depression mainly originated from the Shahezi Formation,and secondarily from the Yingcheng Formation.The contribution of the Huoshiling Formation gas source rocks is relatively small. 相似文献