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31.
This paper first presents the molecule design and synthesis of crown-link type alkyd resin,and its enrichment behaviour for potassium ion in low concentration solution and sea water.On the basis of some theory concepts of Host-Guest chemistry developed in recent years,we have designed and synthesized a new polymer enrichment agent of crow-link resin for potassiumion,i.e.,polymacrocyclic ether bislactone of diethylene glycolpyromyllitic acid(briefly called crown-link type alkyd resin or PBL resin).The yield was about 97.4%,almost quantitatively.  相似文献   
32.
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   
33.
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 of transport 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 Qarban 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 Qarban Salt Lake.  相似文献   
34.
利用ETM多光谱遥感图像,在对盐湖区的遥感影像特征和主要地物光谱特征分析的基础上,通过波段组合变换,压抑粘土及砂砾层等地物的影响,将盐类矿产信息增强提取出来。对比前人的钾盐矿田勘查成果,所提取的盐类信息异常与现代新盐带、湿盐滩和现正在开采的钾盐矿区十分吻合。结合区域地质背景与成矿条件的分析研究,圈定了4个预测区、9处有利地段,为进一步盐类矿产勘查提供了科学依据和目标地。  相似文献   
35.
The structure of the Glueckstadt Graben has been investigated by use of 3D gravity backstripping technique and by 2D gravity and magnetic modelling. Subtracting the gravity effects of the Meso-Cenozoic sediments together with Permian salt reveals a positive residual anomaly within the Glueckstadt Graben. This anomaly includes two local maxima over the Westholstein and Eastholstein Troughs. The 2D gravity models point to the presence of a high-density body within the lower crust of the Glueckstadt Graben. In addition, the results of 2D magnetic modelling indicate that the central part of the high-density body is overlain by an area with high susceptibility. Most probable, the formation of this high-density body is a result of complex poly-phase tectonic history of the study area. Finally, the results of gravity modelling indicate that Permian salt is not homogeneous. 3D gravity analysis and, especially, 2D gravity modelling have distinguished the differences in degree of salt saturation in salt-rich bodies, and elucidate the proportion of Rotliegend salt.  相似文献   
36.
西藏扎布耶盐田盐渍土的改性配比试验   总被引:1,自引:0,他引:1  
根据盐渍土的物理化学性质,采用掺入不同比例石灰或水泥的方法进行改性处理。经击实、抗剪和抗压强度试验结果表明,盐渍土掺入石灰或水泥改性后,混合料的最大干密度、最优含水率、强度指标等均有增加,特别是内聚力迅速增长。研究表明,盐渍土混合料的性状得到了明显改善,改性后的混合料可用于修建盐田埝堤类相关工程。  相似文献   
37.
Definition and measurement of salinity in salt lakes   总被引:4,自引:0,他引:4  
Salinity is the most important chemical attribute of athalassic salt lakes. Even so, some confusion persists of what salinity means and how to measure it. For sal lakes, salinity is best defined as the sum total of all ion concentrations, or total ion concentration. Ideally, it is recommended that salinities be expressed on a mass per mass basis and as ppt (parts per thousand). Direct measurements of salinity can only be derived from full ionic analyses. Indirect measurements can be derived by determinations of density, conductivity, freezing point depression and total dissolved solids or matter.  相似文献   
38.
根据袁见齐教授“高山深盆”成盐模式,探讨新疆天山对第四纪盐类矿床的形成和控制作用,阐述了天山地貌、气候、水文特征与盐类矿产的分布规律和特征。认为“高山深盆”并非一定是四周环山的深盆,可以是某一高山与其间深盆或两侧盆地的有机组合。高山的屏障作用造成了垂直的气候分带,在潮湿多雨的山区利于成盐组份的析出并迁移到干旱少雨的闭流深盆中,形成盐类矿床。  相似文献   
39.
The zooplankton of two salt ponds at Aveiro was studied to evaluate its density and diversity. Samples were collected biweekly from the salt ponds Esmolas and Tanoeiras. Samples were first separated into Holoplankton (Copepoda, nauplii,Acartia, Ostracoda and Anostraca) and Meroplankton (Mollusca, Insecta, annelidan larvae and Ichthyoplankton). The Holoplankton was mainly composed of:Acartia tonsa, Acartia sp.,Eurytemora velox, Artemia sp., and harpacticoids and calanoids. In both salt ponds, species diversity was identical, but total zooplankton density was higher in the Tanoeiras salt pond, probably because its physical and chemical characteristics allowed the development of stable communities.  相似文献   
40.
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