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1.
Zintl化合物是以Edward Zintl命名的化合物,是一类由电正性的碱金属或碱土金属与电负性的13族或14族元素形成的特殊金属间化合物。其价键模式可以是离子键、金属键和共价键共存,其中的准金属可以共价键的形式形成各种形式的离子簇,因而其结构复杂多样。这类化合物的部分阴离子簇不仅具有稳定的笼状、层状和链状结构,并且具有特殊的光、电、磁等性能,使得在半导体、催化、电极材料等方面都有应用的前景和发展潜力。介绍了几个特殊Zintl化合物体系,盐湖丰产元素在Zintl化合物中的作用,指出了含有盐湖丰产元素的Zintl化合物的应用前景和方向。 相似文献
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Zintl化合物是以Edward Zintl命名的化合物,是一类由电正性的碱金属或碱土金属与电负性的13族或14族元素形成的特殊金属间化合物。其价键模式可以是离子键、金属键和共价键共存,其中的准金属可以共价键形成各种形式的离子簇,因而其结构复杂多样。这类化合物的部分阴离子簇不仅具有稳定的笼状、层状和链状结构,并且具有特殊的光、电、磁等性能,使得在半导体、催化、电极材料等方面都有应用的前景和发展潜力。介绍了几个特殊Zintl化合物体系,盐湖丰产元素在Zintl化合物中的作用,指出了含有盐湖丰产元素的Zintl化合物的应用前景和方向。 相似文献
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东昆仑山南、北两侧富锂盐湖成因的氢、氧和锶同位素指示 总被引：2，自引：0，他引：2
青海省富锂盐湖主要分布在东昆仑山南、北两侧,目前对于其水体来源和锂元素的富集规律存在较大争议。通过可可西里盆地富锂盐湖与周边淡水湖或咸水湖湖水中氢、氧同位素组成的对比,揭示富锂盐湖成因与特殊的物源补给有关;可可西里盆地和柴达木盆地中富锂盐湖的水体来源具有相似性,在锂的物源上可能与布喀达坂峰热泉水有关。锶同位素组成表明,那仁郭勒河河水是由100份昆仑山冰川融水与1份深部热泉水混合形成,而柴达木盆地富锂盐湖晶间卤水是由258份那仁郭勒河水与1份盆地西北部迁移卤水混合、蒸发和浓缩形成。总之,可可西里盆地富锂盐湖与沿断裂带以潜流形式或湖盆底部直接补给的热泉水有关,而接受热泉水补给的那仁郭勒河则提供了柴达木盆地东台吉乃尔湖、西台吉乃尔湖和一里坪盐湖近95%的锂元素。 相似文献
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盐湖资源开发利用过程的智能控制对于智慧盐湖、世界级盐湖基地的的建设具有重要意义。利用集成的摩擦纳米发电机网络阵列,不仅可以对野外盐湖区的机械能采集实现金属管道的自供电腐蚀防护,还可实现基于自供能传感器的水流流速检测、水位监测、盐溶液快速现场检测、溶液的 pH检测等。因此,基于摩擦起电效应的自供电传感网络是实现盐湖化工过程智能控制的潜在解决方案。为了促进摩擦纳米发电机的应用,提高摩擦纳米发电机的输出功率一直是科研人员关注的热点。文章在概述了通过表面改性对材料摩擦起电效应强化的研究进展后,进一步分析了改性后的摩擦纳米发电机输出性能提升的原因。主要介绍了物理表面改性和化学表面改性方法。对改性过程中常见的处理操作方法进行了阐述。对物理改性和化学改性的优势和不足进行了总结。分析指出,新的摩擦材料的选择与设计、材料的表面改性仍会是未来一段时间内的研究热点,而性能优异的摩擦纳米发电机可以为盐湖产业的可持续发展提供一种新的方案。 相似文献
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我国350多个盐湖湖表卤水水化学成分综合研究表明,成矿元素K、Li、B主要分布在青藏高原地区,但新疆一些富K、B盐湖也具有较好的开发潜力。我国盐湖卤水中的Br、I、Rb、Cs呈现明显的区域分异,富Br和I盐湖主要分布在内蒙古的中东部,而Rb和Cs则主要分布在青藏高原地区。我国盐湖区按主要成矿元素禀赋情况可以分为3种类型,K+B+Li资源综合利用型;K+B(Li)资源综合利用型以及单一的K(B或Li)资源利用型。青藏高原地区的盐湖卤水矿床以前两者为主,新疆和内蒙的盐湖则以后两者为主。 相似文献
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大柴旦盐湖因蕴藏固体和液体硼矿资源成为柴达木盆地诸多盐湖中最早被关注和开发的盐湖之一;不仅如此,还沉积有全球少有分布的湖底特色柱硼镁石矿床。基于大柴旦盐湖硼矿床的地质特征和硼同位素地球化学特征,与国内外不同硼矿床开展对比研究,旨在探讨主控硼矿床形成的影响因素及其异同点。研究发现,大柴旦盐湖硼矿床与国内外硼矿床的形成均受控于新构造运动、封闭—半封闭的低洼汇水盆地以及极度干旱的气候条件等因素,所有硼矿床均与火山岩或含电气石花岗岩有密切关联,成矿物质特别是硼元素主要来源于火山岩或含电气石花岗岩,经热泉水、温泉水和大气降水的水岩作用后迁移富集。主控因子化学组分或盐湖水化学特性的不同致使硼矿物的种类和矿物共生组合特征等方面表现出一定的差异性。 相似文献
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盐湖是我国重要的无机盐矿产资源，盐湖资源的开发与综合利用，是盐湖化学化工的立足点与归宿．本文侧重应用与发展研究就我国盐湖化学化工在“九·五”期间的发展，提出了战役设想．其总体目标是组建盐湖资源综合利用工程技术研究中心，加速科研成果向生产力的转化；使我国盐湖丰产的钾、硼、锂、镁等盐类资源的开发，在采用高新技术、生产高附加值系列产品、建立综合利用示范企业三个方面取得突破性进展．可供制订规划和组织科研项目时参考． 相似文献
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作为特殊类型资源的盐湖,有重要的科学意义、经济价值和环境效应,是重要矿产的宝库,其中蕴藏的锂、钾都是对国家经济社会发展具有战略意义的宝贵资源。进入21世纪以来,盐湖资源开发的特点就是发达国家和新兴经济体国家都对这些重要资源的极其注重,众多国家参与到开发者的行列中来,特别是参与到南美盐湖资源的开发热潮中来。从资源勘探、评价、开发试验,到产品投放到市场和下游产品开发,以及资金注入、产销体系的建设都非常迅速。可以预料盐湖资源开发的新局面,甚至是新的垄断局面在不久的将来即将形成。 相似文献
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本文对马来半岛中央金成矿带北段的New Discovery金矿地球化学特征进行了分析。主要得出:主量元素特征表明该矿床火山碎屑岩为钙碱性铝过饱和系列岩石。微量元素表明可将13种元素分成4个组合:Cr、Co、Cu、Sc、W、Ba;Pb、Ag、Zn;Sb、Ni;Bi、Mo。第一组合为成矿成晕组合,第二组合为多金属矿化组合,第三组合为硫化物蚀变组合;元素组合也对应于不同的矿化阶段。稀土元素分析结果表明,该岩石属轻稀土富集型,铕弱负异常。稀土配分曲线为平缓的右倾。New Discovery金矿床的原岩为中性火山岩,且形成于岛弧——活动大陆边缘区域。 相似文献
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制造业内部产业关联与空间分布关系的实证研究 总被引：3，自引：3，他引：0
聚焦于中国制造业内部的产业关联与空间分布,基于《中国投入产出表》中涉及的17个制造业细分行业和中国286个地级市空间单元的统计数据,研究与某一制造业细分行业具有较强产业关联的其他制造业细分行业与其空间分布之间是否存在相关性,并进一步分析产业关联强且具有空间关联的产业组合的主要特征。研究表明,在68个产业关联较强的产业组合中,有39个产业组合具有空间关联;产业关联较强的劳动/劳动密集型制造业和资本/技术密集型制造业更容易呈现空间关联;超过半数的制造业细分行业的产业关联和空间关联的程度之间存在正相关。此外,在产业特征分析基础上,利用GWR模型对39个产业关联强且具有空间关联的产业组合的空间关联度在空间分布上的特征和差异进行分析。结果显示,产业组合的空间关联度较高区域多分布在中等发展水平省区,而在经济发达或欠发达省区分布较少;东北三省区空间关联度较高的产业组合基本一致,产业发展情况较为相似。 相似文献
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戈壁表层沉积物地球化学元素组成及其沉积意义 总被引：6，自引：5，他引：1
作为干旱、半干旱区的一类重要荒漠景观,戈壁在中国分布面积较广,其独特的物质组成和沉积特征对解释它的物源和发生过程有重要的意义.本文通过筛分处理对戈壁表层不同粒径沉积物地球化学元素组成进行了分析.结果表明:各类戈壁表层沉积物的主要元素组成特征基本相似,但不同粒级沉积物主要元素的含量略有差异.与UCC的平均化学组成相比,戈壁表层沉积物中主要元素除Si基本与UCC保持一致外,其余各主要元素均在不同程度上表现出了富集和淋失特征,微量元素在两大类型戈壁中随沉积物粒径的变化与主要元素基本一致.在极端干旱的气候条件下戈壁表层沉积物缺少有效的化学风化过程,基本处在未受或较弱的大陆化学风化的初、中级阶段.各个粒级的沉积物在经历侵蚀和风化过程中较好的继承关系表明,戈壁砾石层下伏的细粒沉积层不是外源搬运沉淀,而是局地岩屑通过就地风化和成壤作用形成. 相似文献
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空间数据的多尺度表达问题已成为GIS研究的重点,也是地图自动综合的瓶颈。智能化的多尺度表达是亟须解决的问题。利用小波分析中的多分辨率分析原理,建立微分角度的线状要素简化模型,结合空间要素多尺度表达的特征,研究空间线状要素的简化方法,并对简化后的图形拓扑一致性做简单分析,实现线状要素的简化。 相似文献
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V. I. Kara 《自然地理学》2013,34(1):57-68
The structure and morphology of the floor of the West Australian Basin and adjacent areas are described. Four main levels of the floor are identified according to geographic zonality and morphology. Structural-geomorphological elements of the basin's rim are subdivided into two groups: those formed simultaneously with the formation and evolution of the continental margin and those formed during intensive subsidence and fracturing of the outer part of the basin. 相似文献
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基于协同理论的旅游综合体演化过程与机制研究——以杭州西溪国家湿地公园为例 总被引：2，自引：1，他引：1
选取杭州西溪国家湿地公园作为案例地,引用协同理论为指导,探讨了旅游综合体的演化过程与机制,认为西溪国家湿地公园是由多要素组成的协同系统,经历了旅游产业要素“集聚-共生-融合”的演化过程,萌芽、成长和完善3个阶段集聚的分别是传统旅游业态要素、新兴旅游业态要素和创新旅游业态要素。演化本质是协同系统序参量的变化,不同演化阶段序参量各异,萌芽阶段体现为要素集聚,受外部经济效益驱动;成长阶段体现为要素共生,受内部要素结构调整驱动;完善阶段体现为要素融合,受创新驱动。演化动力是要素间的非线性作用,通过系统内部与外部的能量交换及子系统间相互作用所形成的反馈机制来实现。选取房价作为指标,采用均质与非均质空间比较法测定了西溪国家湿地公园的空间溢出效应。旅游业与相关产业协同创新是西溪国家湿地公园发展模式的主要特征,具体表现为以优良的资源禀赋和广阔的市场为基础,以旅游业为核心,吸引相关产业要素集聚,形成共生和融合效应,发展过程中注重外部物质能量交换和内部自组织调控。 相似文献
18.
PHYSICO‐GEOCHEMICAL AND MINERAL COMPOSITION OF NEEM TREE SOILS AND RELATION TO ORGANIC PROPERTIES 
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下载免费PDF全文 WILLIAM C. MAHANEY JOAN VOROS RAMANATHAN KRISHNAMANI RONALD G.V. HANCOCK SUSAN AUFREITER MICHAEL W. MILNER CHRISTOPHER C.R. ALLEN 《Geografiska Annaler: Series A, Physical Geography》2016,98(2):143-154
The Neem tree, the oil of which has a long history of pesticide, fertilizer and medicinal use in India, has been studied extensively for its organic compounds. Here we present a physical, mineralogical and geochemical database resulting from the analyses of two Neem soil profiles (epipedons) in India. Neem tree derivatives are used in the manufacture of a variety of products, from anti‐bacterial drugs and insecticides to fertilizers and animal feeds. A preliminary geochemical and mineralogical analysis of Neem soils is made to explore the potential for chemical links between Neem tree derivatives and soils. Physical soil characteristics, including colour, texture and clay mineralogy, suggest the two pedons formed under different hydrological regimes, and hence, are products of different leaching environments, one well‐drained site, the other poorly drained. Geochemically, the two Neem soils exhibit similarities, with elevated concentrations of Th and rare earth elements. These elements are of interest because of their association with phosphates, especially monazite and apatite, and the potential link to fertilizer derivatives. Higher concentrations of trace elements in the soils may be linked to nutritional derivatives and to cell growth in the Neem tree. 相似文献
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Iréne Malmsten & Kurt Boström 《Geografiska Annaler: Series A, Physical Geography》2002,84(3&4):245-259
The Kärkejokk (jokk = Lappish for brook) is rich in sulfate and calcium, both elements having been considered enigmatic. To resolve these problems we collected waters at 13 sites during 27 June to 1 September 1996. Nine sites were in the Kärkevagge, and the others in the drainage towards lake Torne Träsk. Rain waters were collected the same period. Conductivity, pH, and temperature were measured in the field, whereas salt load and the elements Na, K, Ca, Mg, S, Si, Fe, Al, Mn, Zn, Sr, and Ba were determined in the laboratory.
Mixing models based on rain water and leaching products of the major bedrocks do not explain observed element patterns except in the lower parts of the jokk. However, oxidation of pyrite has formed acid, sulfate–rich solutions that released Ca and Mg from limestones, and Fe, Mn, Al, and Si, from black shales (Malmsten 1998; Malmsten et al. 2000). Conservative mixing models, using rain water, leached bedrock and pyrite, match the jokk waters quite well, and sulfur isotope data corroborate these findings. The nearby Låktajokk, and Vassijokk also contain much S.
Where these waters debouch they may deposit Si, Al, and Ca, but only little S on various rocks. Total rock analyses, thermodynamic and X–ray data suggest that gypsum, barite, or alunite are not formed in major quantities.
These models show that the hydrogeochemistry of the Kärkejokk may be less enigmatic than often assumed. 相似文献
Mixing models based on rain water and leaching products of the major bedrocks do not explain observed element patterns except in the lower parts of the jokk. However, oxidation of pyrite has formed acid, sulfate–rich solutions that released Ca and Mg from limestones, and Fe, Mn, Al, and Si, from black shales (Malmsten 1998; Malmsten et al. 2000). Conservative mixing models, using rain water, leached bedrock and pyrite, match the jokk waters quite well, and sulfur isotope data corroborate these findings. The nearby Låktajokk, and Vassijokk also contain much S.
Where these waters debouch they may deposit Si, Al, and Ca, but only little S on various rocks. Total rock analyses, thermodynamic and X–ray data suggest that gypsum, barite, or alunite are not formed in major quantities.
These models show that the hydrogeochemistry of the Kärkejokk may be less enigmatic than often assumed. 相似文献
20.
Iréne Malmsten & Kurt Boström 《Geografiska Annaler: Series A, Physical Geography》2002,84(3-4):245-259
The Kärkejokk (jokk = Lappish for brook) is rich in sulfate and calcium, both elements having been considered enigmatic. To resolve these problems we collected waters at 13 sites during 27 June to 1 September 1996. Nine sites were in the Kärkevagge, and the others in the drainage towards lake Torne Träsk. Rain waters were collected the same period. Conductivity, pH, and temperature were measured in the field, whereas salt load and the elements Na, K, Ca, Mg, S, Si, Fe, Al, Mn, Zn, Sr, and Ba were determined in the laboratory.
Mixing models based on rain water and leaching products of the major bedrocks do not explain observed element patterns except in the lower parts of the jokk. However, oxidation of pyrite has formed acid, sulfate–rich solutions that released Ca and Mg from limestones, and Fe, Mn, Al, and Si, from black shales (Malmsten 1998; Malmsten et al. 2000). Conservative mixing models, using rain water, leached bedrock and pyrite, match the jokk waters quite well, and sulfur isotope data corroborate these findings. The nearby Låktajokk, and Vassijokk also contain much S.
Where these waters debouch they may deposit Si, Al, and Ca, but only little S on various rocks. Total rock analyses, thermodynamic and X–ray data suggest that gypsum, barite, or alunite are not formed in major quantities.
These models show that the hydrogeochemistry of the Kärkejokk may be less enigmatic than often assumed. 相似文献
Mixing models based on rain water and leaching products of the major bedrocks do not explain observed element patterns except in the lower parts of the jokk. However, oxidation of pyrite has formed acid, sulfate–rich solutions that released Ca and Mg from limestones, and Fe, Mn, Al, and Si, from black shales (Malmsten 1998; Malmsten et al. 2000). Conservative mixing models, using rain water, leached bedrock and pyrite, match the jokk waters quite well, and sulfur isotope data corroborate these findings. The nearby Låktajokk, and Vassijokk also contain much S.
Where these waters debouch they may deposit Si, Al, and Ca, but only little S on various rocks. Total rock analyses, thermodynamic and X–ray data suggest that gypsum, barite, or alunite are not formed in major quantities.
These models show that the hydrogeochemistry of the Kärkejokk may be less enigmatic than often assumed. 相似文献