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1.
富钴结壳成因探讨   总被引:1,自引:0,他引:1  
富钴结壳(Cobalt-ch ferromanganese crusts)是继多金属结核、锰结核之后被人类发现的又一深海矿产资源,由于其所处深度比锰结核浅,并且战略金属钴的含量较高,因此成为当前国际的研究热点。本文主要从矿物岩石学、地球化学、同位素、生物地层学等方面对成因问题进行了分析。  相似文献   
2.
黄土发育表土结皮过程和微结构分析的试验研究   总被引:13,自引:0,他引:13  
对采自晋西离石的马兰黄土进行了模拟降雨试验,研究表土微结构与表土结皮发育过程的关系.模拟降雨强度为1.2mm/min,降雨历时为1~30min.通过对表土微结构的变化观测可以清楚看到,在30min降雨过程中经历了两次表土结皮的形成过程.初始形成的表土结皮是很不稳定的,在表土结皮的初期发育阶段较容易被破坏.在稍后阶段形成的表土结皮会更加稳定.观测到的表土微结构变化过程揭示出它们是呈周期性变化:团聚体被破坏、土壤颗粒发生垂直和水平位移、表土结皮层和淋溶层的孔隙和结构不断形成和破坏、表土结皮的形成破坏、表土变得比较密实.土壤抗剪强度可以用标准锥体贯入仪来测定,由土壤含水量和土壤抗剪强度关系得到的表土结皮强度指标与观测到的表土微结构变化密切相关.  相似文献   
3.
Based on results of nannofossil analysis and 10Be dating in ferromanganese crusts M1-1 and A1-1 (no nannofossils were found in it),from the western and central Pacific respectively,it is found that the crust growth ages from nannofossil biostrati-graphy agree well with those based on 10Be isotope analysis. Both crusts have three growth layers,and the oldest layer was deposited in Miocene at about 12.80 Ma. The maximum,minimum,and average growth rates of crust A1-1 (from the central Pacific) are 8.11,1.92 and 3.47 mm/Ma,and those of crust M1-1 (from the western Pacific) are 2.93,0.47,and 0.94 mm/Ma.  相似文献   
4.
Nanometer properties of oceanic polymetallic nodules and cobalt-rich crusts   总被引:4,自引:0,他引:4  
An ammonia leaching process was utilized to extract Co, Ni and Cu from oceanic polymetallic nodules, whereas an acid leaching process was utilized to extract Co, Ni, Cu, Zn and Mn from cobalt-rich crusts. Both processes produced nanometer materials—ammonia leaching residue and acid leaching residue. A systematic study was conducted on the phase, composition and physicochemistry properties of these residues. The result shows that both residues contain a large amount of nanometer minerals. Ammonia l eaching residue mainly consists of rhodochrosite, with the average grain diameter of 17.9 nm; whereas the acid leaching residue mainly consists of well-developed bassanite, with the average grain deameter of 9.5 nm. The bassanite also has a microporous structure, the volume of the pore space is 1.23 × 10−2 mL/g. Both the ammonia and acid leaching residues have a large specific surface area, and they display a strong adsorption capacity to saturate sodium chloride vapour, N2 and SO2. Both residues have high contents of rare earth elements, and most of these elements exist in the state of ionic adsorption. The content of σ FeO is high. The P2O5 enrichment is observable in acid leaching residues. The unique composition and nanometer solid properties of the leaching residues displayed their potential value and promised a bright future for their application in the field of environmental protection and materials.  相似文献   
5.
Microbial crusts are attracting much interest in view of their possible uses in environmental conservation and ecological restoration of the arid and semiarid regions.Because algae play an irreplaceable important role in the early formation and the strengthening of microbial crusts,they are paid much more attention to than other cryptogams.In this paper,an overview of the current knowledge on the fine structure and development of microbial crust,focusing on the algal biomass,vertical distribution,succession,influential factors on algae,cohesion of soil stabilization,cementing mechanism for soil particles and the microalgal extracellular polymers is given,with particular emphasis on the authors' researches,and some prospects are put forward as well.  相似文献   
6.
钴结壳破碎块度是衡量螺旋滚筒式采矿头破碎效果的重要指标,也是集矿和扬矿系统的设计依据.对常用的4种矿岩破碎粒度分布公式进行了分析,利用线性回归按4种分布公式对实验数据进行拟合,得出分形分布能更准确地描述钴结壳破碎块度分布特征,分维数能定量描述富钴结壳破碎的块度组成,图2,表2,参10.  相似文献   
7.
海底钴结壳的开采,需要一种能适应海底特殊条件、针对钴结壳特殊性能的开采方法.作者根据现有钴结壳开采方法,提出了激振破碎开采法,并研究了相关机电技术:通过调节激振频率及振幅以适应厚度差距较大的钴结壳分布状况;激振作业不需反力以适应高低不平、悬崖遍布的海底地形;通过比例电液减压阀来改变液控变量马达的排量以改变激振频率;通过结合比例电液减压阀、密封氮气压力位移转换器和机液伺服阀以实现对独立回转的2个偏心体进行等偏心距控制,以消除侧向振动.研究结果表明:该开采方法装备能使破碎设备在海底斜坡上作业,即使悬吊于悬崖堑沟之中也能正常作业;设备能根据钴结壳自身特点进行参数最优调节,实现高效共振剥落.  相似文献   
8.
9.
建立了水射流系统的动力学模型,通过仿真研究获取了水射流系统参数与水射流切削性能的作用规律.仿真结果表明:水射流的有效作业距离为水射流的等速区长度;水射流的工作压力越高,水射流的出口速度越大;喷嘴的轴向射流速度变化与围压无关.开展了水射流切削钴结壳模拟料性能实验研究.实验结果表明:水射流切削钴结壳模拟料时存在一个门槛压力...  相似文献   
10.
针对大洋富钴结壳开采过程中微地形的复杂性,论述了富钴结壳开采的采集率、废石混入率与切削深度间的关系,进一步分析了在开采中达到某一控制废石混入率时,与切削深度相应的采集率所出现的多极值性问题;在此基础上,引入了遗传算法,并利用其全局寻优性成功地解决了在达到控制废石混入率时获得最大采集率的切削深度的控制问题.文中给出了遗传算法在解决本问题中的具体实施过程,并对实例进行了计算,得出了满意的结果.从而为大洋深海开采的切削深度的控制提出了一解决途径.图4,表1,参12.  相似文献   
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