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101.
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
102.
In order to prepare calcium phosphate-based material with nano-structure and bioactivity, natural lecithin and n-tetradecane were used as the amphipile and the oil phase respectively, along with the water phase, to form a microemulsion template. Phosphate mineralization was induced and controlled by the microemulsion. The products, characterized by scanning electronic microscopy, infrared spectroscopy and X-ray diffraction analysis, are composed of lecithin and hydroxyapatite, and possess the nano-structure of sticks, balls and three-dimensional nets connected by tubes. These results show that the microemulsion can be used to control calcium phosphate mineralization for the preparation of biomimetic mineral materials with various nano-structures. 相似文献
103.
通过马氏试验结果,验证了碎石矿质混合料级配最大密度时,实验指数为0.45的合理性。同时对级配曲线半对数坐标、常数坐标、幂指数坐标三种形式的优缺点进行了详细分析,从理论上论述了幂指数坐标是级配曲线的最佳坐标形式。最后用球体理论、干涉理论对实验指数为0.45时,取得最大理论密度这一现场作了具体理论分析。 相似文献
104.
通过试验与理论分析,在比较陶粒轻骨料混凝土与普通混凝土板受力特性差异的基础上.对轻骨料混凝土板冲切破坏机理作了进一步探讨.在建立冲切破坏模式的基础上提出适合于轻骨料混凝土板冲切强度的计算公式. 相似文献
105.
106.
苗胜坤 《大连理工大学学报》1993,(Z1)
从理论上提出了降低隔河岩水利枢纽砼人工骨料开采大块率的小抵抗 线深孔微差爆破技术.通过现场试验确定了合理的钻爆参数和微差起爆方 式,给出了相应的技术措施. 相似文献
107.
108.
李治华 《中南大学学报(自然科学版)》1993,(1)
本文研究了含镁脉石矿物(蛇纹石、橄榄石和辉石)对镍黄铁矿浮选的影响。通过显微电泳试验、电镜扫描检查、吸附试验、微型浮选试验和产物物质组成研究等,查明了产生影响的原因、程度和作用机理;并找到了防止或消除其影响的方法。 相似文献
109.
本文介绍了以甲基硅油─—液体石蜡为主体消泡组分,辅以多种乳化剂和助剂,在水相中复合而成的消泡剂。讨论了消泡效果,乳液稳定性和制备工艺。 相似文献
110.
Genesis of zircon and its constraints on interpretation of U-Pb age 总被引:242,自引:10,他引:232
WUYuanbao ZHENGYongfei 《科学通报(英文版)》2004,49(15):1554-1569
Zircon U-Pb dating is the most commonly used method for isotopic geochronology. However, it has been a difficult issue when relating zircon U-Pb ages to metamorphic conditions in complex metamorphic rocks. Much progress has been made in the past decade with respect to the genesis of zircon and its constraints on interpretation of U-Pb age. Three methods have been proposed to link zircon U-Pb age to metamorphic conditions: ( i ) internal structure; ( ii ) trace element feature; (iii) mineral inclusion composition. Magmatic zircon shows typical oscillatory zoning and/or sector zoning, whereas metamorphic zircon has internal structures such as no zoned, weakly zoned, cloudy zoned, sector zoned, planar zoned, and patched zoned ones. Zircons formed in different geological environments generally have characteristic internal structures. Magmatic zircons from different rock types have variable trace element abundances, with a general trend of increasing trace element abundances in zircons from ultramafic through mafic to granitic rocks. Zircons formed under different metamorphic conditions have different trace element characteristics that can be used to relate their formation to metamorphic conditions. It is an effective way to relate zircon growth to certain P-T conditions by studying the trace element partitioning between coexisting metamorphic zircon and garnet in high-grade metamorphic rocks containing both zircon and garnet. Primary mineral inclusions in zircon can also provide unambiguous constraints on its formation conditions. Therefore, interpretation of zircon U-Pb ages can be constrained by its internal structure, trace element composition, mineral inclusion and so on. 相似文献