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1.
为改善孔雀石的硫化浮选效果,通过浮选试验,系统研究了孔雀石单矿物分段硫化浮选行为及动力学基因特性规律,确定了孔雀石的最佳硫化浮选段数。结果表明:硫化时间过长,孔雀石可浮性降低,适量硫化钠能提高孔雀石浮选速率,但浮选速率随时间延长而降低;硫化钠用量为 4 mg/L,硫化时间为 1 min,丁基黄药用量为 80 mg/L 时,孔雀石可浮性最好;添加碳酸铵可以改善孔雀石的浮选效果,当碳酸铵用量为 50 mg/L 时,对孔雀石活化效果最佳;分段硫化浮选过程中,每段孔雀石的浮选速率高低与浮选药剂的质量分配比例有关;适当增加硫化浮选段数,可以提高孔雀石的总回收率;孔雀石的最佳硫化浮选段数为三段,各阶段浮选药剂分配比例为 4∶2∶2。 相似文献
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针对冬瓜山入浮颗粒粒度较粗且粒度组成分布不合理问题,基于磨矿产品的粒度分布及矿石力学性质对磨矿介质配比进行调整以优化入浮颗粒的粒度组成,结果表明:冬瓜山一段磨矿介质尺寸方案为m (φ60):m (φ40):m (φ30):m (φ25)=40:10:30:20,采用推荐方案可提高磨矿产品中-0.1+0.01 mm颗粒产率2.28%。推荐方案与现场方案磨矿产品经一粗两精两扫的浮选闭路对比试验,推荐方案铜精矿回收率90.11%,较现场方案提高1.34%,精矿品位提高了0.94%。对浮选尾矿筛分并检测分析可知推荐方案磨矿产品在-0.1+0.01 mm颗粒中铜的回收效果优于现场方案,利用推荐的介质配比方案优化磨矿产品粒度组成,有效提高了冬瓜山选铜浮选指标。 相似文献
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层状硅酸盐矿物滑石在解离时会形成具有明显性质差异的2种表面,滑石的晶面各向异性会导致矿物不同表面表现出不同的润湿性以及不同的电荷密度。通过原子力显微镜力(AFM)曲线测量以及经典DLVO理论计算,对滑石的非极性面和极性面进行深入研究,首先利用AFM力曲线测量和计算,得到不同pH值时氮化硅的电位值,利用AFM直接力测量法对符合粗糙度要求的滑石非极性面和极性面样品在10 mmol/L的KCl溶液中进行测量,得到不同pH值环境下的力曲线,通过DLVO理论拟合计算得到滑石非极性面和极性面的表面电位值。滑石的非极性面电位值在研究的pH范围内一直为负,且恒定,极性面电位值随pH升高而降低,零电点出现在pH=7.6左右。将计算得到的滑石表面电位与氮化硅之间的作用力拟合曲线与实际测得的作用力进行对比发现,计算值与测量值基本一致,拟合度较高。 相似文献
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《Journal of the European Ceramic Society》2020,40(9):3445-3452
This paper describes and discusses the application of the original sintering process named cold sintering to the electrolyte material BaCe0.8Zr0.1Y0.1O3-δ to enhance its densification at a temperature below that needed in a conventional sintering. This new technique enables the acceleration of the densification resulting in a more compacted microstructure with an unexpected high relative density of 83 % at only 180 °C. A subsequent annealing at 1200 °C further enhances the densification which reaches 94 %. The electrochemical performance of CSP sintered ceramics was investigated and optimized by varying different process parameters. The comparison with the conventional sintered material reveals an increase of the total conductivity by mostly increasing the grain boundary one. This result emphasizes the benefits of CSP to not only reduce the sintering temperature but also to enhance the electrochemical properties. 相似文献
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《材料与设计》2015
Core-shell structured polyacrylic nanoparticles (named CSPN) impact modifiers consisting of a rubbery poly(n-butyl acrylate) core and a rigid poly(methyl methacrylate) shell with a size of about 352 nm were synthesized by seed emulsion polymerization. The CSPN modifier with core-shell weight ratio 80/20 was used to toughen poly(butylene terephthalate) (PBT) by melt blending. With an increase in CSPN content, the impact strength and the elongation at break of PBT/CSPN blends increased significantly compared with those of PBT; however, the tensile strength decreased. It was found that the polymerization had a very high instantaneous conversion (> 93%) and overall conversion (99%). The core-shell structure of CSPN was examined by means of transmission electron microscope. Scanning electron microscope was used to observe the morphology of CSPN particle and fractured surfaces of the blends. The dynamic mechanical analyses of PBT/CSPN blends showed two merged transition peaks of PBT matrix, with the presence of CSPN modifier, which was responsible for the improvement of PBT toughness. The results indicated that the notched impact strength of PBT/CSPN blend with a weight ratio of 80/20 was 8.61 times greater than that of pure PBT where the brittle-ductile transition point appeared. 相似文献
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The electrokinetic and flotation behaviors of hemimorphite in sodium oleate solution were studied. The results of micro-flotation experiments indicate that hemimorphite shows good floatability at pH 4.0–9.0 and pH 11.0. The point of zero charge (PZC) of hemimorphite is pH 5.1. Zeta-potential and FTIR measurements indicate that the mechanism of sodium oleate adsorption on hemimorphite involves both chemical and physical interactions. Sodium oleate mainly reacts with the Zn on the hemimorphite surface. In acid/base pH range, the aggregation among hemimorphite particles which is more likely caused by hydrophobic interaction than electrostatic interaction improves hemimorphite’s floatability. 相似文献
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The flotation response of a typical zinc-lead (Zn/Pb) ore, with respect to coarse composite (sulphide/non-sulphide) particles is reported. The flotation tests were carried out on a selected feed particle size range (−600 + 75 μm, at P80 of 390 μm) and the recovery of Zn composite particles analysed on a size by size basis. The best results were achieved with the use of 75 g/t sodium isopropyl xanthate (SIPX), obtaining a Zn recovery of 77%, with a significant improvement at the coarse end of the particle size distribution. Computerised scanning electron microscope (QEMSCAN) was used to characterise value mineral grain size and degree of liberation, as well as gangue and sphalerite association in particles reporting to both concentrate and tailings. A new characterisation function (Locking ratio, LR) was developed based on the data from the automated mineralogical analysis to characterise particles into two-phase composites with different degree of locking texture (simple and complex). The function, which is based on the mode of occurrence of sphalerite, grain size, proportion and composition of the constituent minerals in each particle, was used to study the flotation response of the particles with different degrees of locking. The results highlight the difference in recoverability of the sphalerite bearing particles with different degrees of locking, with simple locking texture giving higher recovery than complex locking texture, for the same overall liberation. 相似文献