黄铜矿自诱导浮选的研究

本文给出了pH0～12时,黄铜矿无硫化钠无捕收剂浮选(即自诱导浮选)的可浮区和不可浮区。热力学计算表明了可浮区的意义。用热力学计算、电位测量和伏安曲线研究了自诱导浮选疏水体产生机理;表面溶剂提取一化学分析技术建立了黄铜矿表面疏水/亲水平衡关系。研究结果表明,中性硫(S~0)是主要疏水体,其产生和提取量受电位控制。     

氧化铁硫杆菌的微波诱变及对低品位黄铜矿的生物浸出

研究微波辐照诱变氧化铁硫杆菌T.f菌以及浸出低品位黄铜矿的效果。结果表明,微波辐照能够引起浸矿细菌产生变异,提高菌种的活性。诱变菌比原始菌的活性提高了39.96%。T.f菌经微波处理,浸矿性能有明显提高。与T.f菌相比,诱变后的T.f菌对原生铜矿的浸出率提高了31.44%,对易浸的次生硫化铜矿浸出率从53.66%提高到74.97%,总铜浸出率从32.43%提高到56.58%,浸出终点比原始菌提前了5～10d。诱变后的T.f菌对以黄铜矿为主的多金属铜矿具有较好的浸出效果。     

嗜酸氧化亚铁硫杆菌浸出黄铜矿中氧化还原电位、黄铁钾钒和胞外聚合物的关系和影响(英文)

在合成的胞外聚合物(EPS)溶液中,研究不同起始总铁量、不同Fe(III)与Fe(II)摩尔比条件下嗜酸氧化亚铁硫杆菌浸出黄铜矿过程中pH、电位、可溶性铁离子和Cu2+浓度随浸出时间的变化。结果表明:当溶液电位低于650mV(vsSHE)时,因细菌产生的EPS可通过絮凝黄铁钾钒延缓污染,即使铁离子浓度达到20g/L,黄铁钾钒对细菌浸出黄铜矿的阻碍作用也不是致命的,但随着铁离子浓度的增加而增加;细菌氧化的铁离子容易吸附在黄铜矿表面的EPS表层,有黄铁钾钒的EPS层是弱离子扩散壁垒,细菌通过把EPS空间内外的Fe2+氧化成Fe3+,进一步创造高于650mV的电位,导致EPS层离子扩散性能的快速恶化,严重地和不可逆地阻碍生物浸出黄铜矿。     

电位对天然黄铜矿表面膜层性质的影响

采用循环伏安（CV）、扫描电子显微镜（SEM）和电化学阻抗谱（EIS）研究黄铜矿在含有5×10-4mol/L乙黄药溶液中的电化学行为以及电位对黄铜矿表面膜层成分和性质的影响。结果表明：在开路电位（OCP）下,天然黄铜矿表面发生黄药阴离子的吸附过程;在阳极电位范围-0.11～0.2V内,主要发生黄药阴离子氧化形成疏水双黄药膜层的电化学过程。形成的双黄药膜层在电位为0V时具有较高覆盖度和较大的厚度,随着电位的增加表面双黄药膜层的覆盖度和厚度减小。当电位高于0.2V时,黄铜矿表面发生以自身活化溶解为主的电化学过程,黄铜矿表面由双黄药膜层转化成为大量具有多孔和疏松结构的含有Cu（Ⅱ）和Fe（Ⅲ）的氧化物。     

Growth and characterization of Cu(InA1)Se2 by vacuum evaporation

Quaternary chalcopyrite compounds Cu(In_1−xAl_x)Se₂ were prepared by vacuum evaporation method. It is found that the ratio of In/Al determines the nature of semiconducting properties from n-type in the region of In/Al 1 to p-type in the region of In/Al > 1.     

Magnetic Resonance in ZnGeP2 and (Zn,Mn)GeP2

Electron paramagnetic (EPR) and ferromagnetic resonance (FMR) have been studied in the system of (Zn,Mn)GeP₂ ferromagnetic layer grown on undoped ZnGeP₂ single crystal. Strong FMR signals are registered in the wide temperature range up to room temperature. EPR and photo-EPR of intrinsic defects are observed in ZnGeP₂ substrate. EPR spectra characteristic of Mn²⁺ ions on Zn²⁺ sites in the bulk appear after the growth of the ferromagnetic layer on ZnGeP₂ crystal indicating the efficient Mn-diffusion into the bulk crystal by the annealing treatments.     

Cathodoluminescence in transmission electron microscopy

We describe a cathodoluminescence spectrometer that is attached to an analytical transmission electron microscope. After a brief consideration of the set‐up and the peculiarities of recording spectra and of mapping defect distributions in panchromatic and monochromatic cathodoluminescence, we discuss two examples of applications. Emphasis is placed on the potential for obtaining novel information about materials and processes on a microscopic and a nanoscopic scale by combining cathodoluminescence with the structural and chemical information for the same site of the specimen. We select an example concerning the role of In distribution in light emission from InGa/GaN quantum wells and a second one concerning the analysis of the initial electron radiation damage of Cu(In,Ga)Se₂ photovoltaic films.     

Structural,optical and electrical properties of spray pyrolytically deposited thin films of CuInS2

CuInS₂ is a promising chalcopyrite semiconducting material for solar cell fabrication. Using aqueous solutions of cupric chloride, indium trichloride and thiourea, we deposited thin CuInS₂ films on glass at 350°C and studied their structural, optical and electrical properties. From the XRD pattern the chalcopyrite structure of these films was confirmed. The films were polycrystalline. The grain size estimated from scanning electron micrographs was found to be of the order of 1μm. Resistivity of the film was measured for temperatures ranging from 77 to 473 K. Band gap values were determined from optical transmission data. Hall mobility and carrier concentration at room temperature were calculated using Van der Pauw-Hall method.     

Influence of galvanic interaction between chalcopyrite and some metallic materials on flotation

Galvanic interactions between the grinding media and the ground mineral inside a ball mill could not only accelerate the media wear but also adversely affect the flotation response of the ground mineral. Rest potential, combination potential and galvanic current measurements were carried out to understand the probable electrochemical interactions between chalcopyrite and several metallic electrodes such as platinum, stainless steel, hyper steel, mild steel and cast iron. Flotation recovery of chalcopyrite was found to be significantly lowered when contacted with hyper steel, mild steel or cast iron prior to flotation unlike with platinum or stainless steel. The influence of the presence of collector during galvanic interaction as well as the effect of relaxation for fresh and galvanically interacted chalcopyrite samples were also studied with respect to its floatability. AES and ESCA analyses indicated that galvanic coupling of chalcopyrite with a hyper steel grinding medium resulted in the formation of hydroxide or oxide species of iron on the mineral surface. An electrochemical mechanism is proposed to explain the mineral-grinding media interaction and its effect on flotation.     

pH对黄铜矿细菌浸铜的影响

通过摇瓶试验考察初始pH对黄铜矿细菌浸出的影响。结果表明,在初始pH为1.2~1.6时,细菌活性较好,亚铁离子的氧化速率快;初始pH为1.4时细菌对黄铜矿的浸出体系适应性较好;pH为1.2~1.4的浸出体系中黄钾铁钒生成量较少,铜浸出率较高,矿浆pH也是控制黄钾铁钒沉淀生成的主要因素。