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井中激电测井在金属矿勘探中的应用 被引量:15
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作者 潘建西 《西北地质》 CAS CSCD 2010年第2期190-194,共5页
通过在陕南平利某工区ZK301孔及东、南、西、北4个方向分别布极,极距约100m,进行激电测井工作所取得的井中物探测井曲线图,结合工区的岩(矿)石电性参数特征进行分析,得出在该井深112~137m及202~215m两阶段均为弱矿化带,主要由黄铁矿... 通过在陕南平利某工区ZK301孔及东、南、西、北4个方向分别布极,极距约100m,进行激电测井工作所取得的井中物探测井曲线图,结合工区的岩(矿)石电性参数特征进行分析,得出在该井深112~137m及202~215m两阶段均为弱矿化带,主要由黄铁矿化引起,而在井深225~245m及320~330m两阶段均为强矿化带,主要由闪锌矿化引起。由于钻孔的原因未做其他极距的激电测井工作。并对激电测井工作中应注意事项进行了简单的描述。 展开更多
关键词 陕南平利 井中激电测井 黄铁矿 闪锌矿化 应用
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Bioleaching and electrochemical property of marmatite by Leptospirillum ferrooxidans 被引量:2
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作者 班进荣 顾帼华 胡可婷 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2013年第2期494-500,共7页
The effects of several variables on the bioleaching of marmatite with pure L. ferrooxidans were investigated. The results show that zinc extraction increases with the decrease of pulp density. Adjusting pH tol.6 durin... The effects of several variables on the bioleaching of marmatite with pure L. ferrooxidans were investigated. The results show that zinc extraction increases with the decrease of pulp density. Adjusting pH tol.6 during the bioleaching process has a positive effect to the dissolution of marmatite. External addition of Fe^3+ ions accelerates the bioleaching, while the concentration of additional Fe^3+ over 2.5 g/L weakens the acceleration effect due to the inhibition effect on bacteria growth and the promotion of jarosite production. The electrochemical measurements were used to make further understanding on the dissolution of marmatite with and without additional Fe^3+ in the presence of L. ferrooxidans. The experimental data illustrate that additional Fe^3+ ions could increase the corrosion current density, which is favorable to zinc extraction. The EIS spectra show that rate-limiting step does not change when Fe^3+ is added. 展开更多
关键词 BIOLEACHING MARMATITE electrochemical measurements L. ferrooxidans
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Zinc isotope fractionation under vaporization processes and in aqueous solutions 被引量:2
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作者 Jixi Zhang Yun Liu 《Acta Geochimica》 EI CAS CSCD 2018年第5期663-675,共13页
Equilibrium Zn isotope fractionation was inves- tigated using first-principles quantum chemistry methods at the B3LYP/6-311G level. The volume variable cluster model method was used to calculate isotope fractionation ... Equilibrium Zn isotope fractionation was inves- tigated using first-principles quantum chemistry methods at the B3LYP/6-311G level. The volume variable cluster model method was used to calculate isotope fractionation factors of sphalerite, smithsonite, calcite, anorthite, for- sterite, and enstatite. The water-droplet method was used to calculate Zn isotope fractionation factors of Zn^2+-bearing aqueous species; their reduced partition function ratio factors decreased in the order [Zn(H2O)6]^2+ 〉 [ZnCl(H2O)5]^ + 〉 [ZnCl2(H2O)4] 〉 [ZnCl3(H20)2]^-〉 ZnCl4]^2-. Gas- eous ZnCl2 was also calculated for vaporization processes. Kinetic isotope fractionation of diffusional processes in a vacuum was directly calculated using formulas provided by Richter and co-workers. Our calculations show that in addition to the kinetic isotope effect of diffusional processes, equilibrium isotope fractionation also contributed nontriv- ially to observed Zn isotope fractionation of vaporization processes. The calculated net Zn isotope fractionation of vaporization processes was 7-7.5‰, with ZnCl2 as the gas- eous species. This matches experimental observations of the range of Zn isotope distribution of lunar samples. Therefore, vaporization processes may be the cause of the large distri- bution of Zn isotope signals found on the Moon. However, we cannot further distinguish the origin of such vaporization processes; it might be due either to igneous rock melting inmeteorite bombardments or to a giant impact event. Fur- thermore, isotope fractionation between Zn-bearing aqueous species and minerals that we have provided helps explain Zn isotope data in the fields of ore deposits and petrology. 展开更多
关键词 Evaporation process Zinc isotope Kineticisotope fractionation Equilibrium fractionation Zincspecies in solution
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Quantum-mechanical study of effect of lattice defects on surface properties and copper activation of sphalerite surface 被引量:15
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作者 陈建华 陈晔 李玉琼 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第6期1121-1130,共10页
The electronic properties of sphalerite(110)surface bearing Fe,Mn and Cd impurities were calculated using density-functional theory,and the effects of impurities on the copper activation of sphalerite were investigate... The electronic properties of sphalerite(110)surface bearing Fe,Mn and Cd impurities were calculated using density-functional theory,and the effects of impurities on the copper activation of sphalerite were investigated.Calculated results indicate that both Fe and Mn impurities narrow the band gap of sphalerite surface and lead to the Fermi level shifting to conduction band.Impurity levels composed of Fe 3d and Mn 3d orbital appearing in band gap are beneficial to electrons transfer from the valence band to the conduction band and promote the surface conductivity and the electrochemical activity.The results show that Fe and Mn impurities cannot be replaced by Cu atom,which reduces the exchange sites(Zn)for Cu atom,hence Fe-and Mn-bearing sphalerites are hard to be activated by copper.Cd impurity has little effect on electronic structure of sphalerite surface;however,Cd atom is easily replaced by Cu atom,and this is the reason why the Cd-bearing sphalerite can be easily floated. 展开更多
关键词 SPHALERITE lattice impurity DFT calculation copper activation
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Bioleaching of sphalerite by Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans cultured in 9K medium modified with pyrrhotite 被引量:5
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作者 陈松 邱冠周 +1 位作者 覃文庆 蓝卓越 《Journal of Central South University of Technology》 EI 2008年第4期503-507,共5页
Elective culture of Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans in 9K medium modified with pyrrhotite was studied.Bioleaching of flotation concentrate of sphalerite by the selected bacteria was ca... Elective culture of Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans in 9K medium modified with pyrrhotite was studied.Bioleaching of flotation concentrate of sphalerite by the selected bacteria was carried out.The results show that the microorganisms cultured by pyrrhotite are a mixture of Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans,of which the capability to oxidize ferrous to ferric irons is enhanced by the high mass ratio of Fe to S in pyrrhotite.Three pyrrhotite samples were separated into various parts with corresponding S/Fe ratios by magnetic separation and were used to culture the elective bacteria as the substrate.The association of the cultures could provide a more rapid and complete oxidation of sphalerite than that of bacteria cultivated by conventional methods. 展开更多
关键词 BIOLEACHING PYRRHOTITE elective culture SPHALERITE
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Sulfur speciation transformation during bioleaching of pyrite-containing sphalerite concentrate by thermophile Sulfolobus metallicus at 65 °C 被引量:4
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作者 夏金兰 赵小娟 +7 位作者 梁长利 杨益 聂珍媛 汤露 马陈燕 郑雷 赵屹东 邱冠周 《Journal of Central South University》 SCIE EI CAS 2012年第7期1961-1966,共6页
Sulfur speciation transformation during bioleaching of pyrite-containing sphalerite concentrate by thermophile Sulfolobus metallicus (S. metallicus) at 65 ℃ was investigated by X-ray diffraction (XRD), diffuse re... Sulfur speciation transformation during bioleaching of pyrite-containing sphalerite concentrate by thermophile Sulfolobus metallicus (S. metallicus) at 65 ℃ was investigated by X-ray diffraction (XRD), diffuse reflectance Fourier transform infrared spectroscopy (FT-IR) and sulfur K-edge X-ray absorption near edge structure spectroscopy (XANES). The results show that the presence of S. metallicus effectively enhances the dissolution of the mineral. The yield of zinc increases from 0.5 g/L in sterile control to 2.7 g/L in bioleaching. The pyrite in the concentrate facilitates zinc dissolution in the early stage, but has hindrance role in the late stage for the formation of jarosite. Sulfur speciation analyses show that jarosite and elemental sulfur are main products in bioleaching process, and the accumulation ofjarosite is mainly responsible for the decline of leaching efficiency. 展开更多
关键词 SPHALERITE BIOLEACHING Sulfolobus metallicus sulfur K-edge X-ray absorption near edge spectroscopy (XANES) sulfurspeciation transformation
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Oxygen pressure acid leaching of artificial sphalerite catalyzed by Fe^3+/Fe^2+self-precipitation 被引量:5
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作者 TIAN Lei GONG Ao +5 位作者 WU Xuan-gao XU Zhi-feng ZHANG Ting-an LIU Yan WEI Kui-xian YU Zhan-liang 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第6期1703-1713,共11页
The mechanism of oxygen pressure acid leaching of sphalerite catalyzed by Fe^3+/Fe^2+self-precipitation was investigated in this study.Artificial sphalerite was fabricated with varying amounts of iron content via the ... The mechanism of oxygen pressure acid leaching of sphalerite catalyzed by Fe^3+/Fe^2+self-precipitation was investigated in this study.Artificial sphalerite was fabricated with varying amounts of iron content via the sintering of ZnS and FeS and used for the pressure acid leaching experiment.The variations in the potential of the pressure leaching system were investigated by using a self-designed potential autoclave.The results showed that compared to the non-iron sphalerite,there was a violent redox reaction between the 25.70%Fe-artificial sphalerite and dissolved oxygen during the process of pressure leaching;and the catalytic mechanism was attributed to the redox couple Fe^3+/Fe^2+,where Fe3+oxidizes the H2S gas film and the reduced Fe2+state is subsequently oxidized by the dissolved oxygen.Furthermore,the effect of temperature,H2SO4 concentration,and oxygen partial pressure on the artificial sphalerite with different iron contents was studied.The sphalerite samples with iron content were observed to dissolve more easily in sulfuric acid compared to the non-iron samples.Moreover,the activation energy of artificial sphalerite was observed to be lower in the sample with 25.70%iron content(22.26 kJ/mol)compared to that with no iron(32.31 kJ/mol);and the apparent reaction orders were obtained with respect to H2SO4 concentration(1.10 and 1.36)and oxygen partial pressure(1.29 and 1.41),respectively.A comprehensive kinetic model was developed on the basis of the experimental data and the fitted leaching ratio plot;and the kinetic equations for the leaching of sphalerite catalyzed by Fe^3+/Fe^2+self-precipitation were determined. 展开更多
关键词 leaching mechanism catalyzed by Fe^3+/Fe^2+self-precipitation potential curves artificial sphalerite leaching kinetics activation energy reaction orders
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Effect of vacancy defects on electronic properties and activation of sphalerite(110) surface by first-principles 被引量:11
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作者 陈建华 陈晔 李玉琼 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第3期502-506,共5页
The electronic properties of sphalerite(110) surface with Zn-vacancy and S-vacancy were calculated by using density-functional theory,and the effects of vacancy defect on the copper activation of sphalerite were inves... The electronic properties of sphalerite(110) surface with Zn-vacancy and S-vacancy were calculated by using density-functional theory,and the effects of vacancy defect on the copper activation of sphalerite were investigated.The calculated results indicate that surface state occurs in the band gap of Zn-vacancy sphalerite,which is from the contribution of S 3p orbital at the first layer of the surface.The presence of S-vacancy results in surface state appearing near the Fermi level and the bottom of conductor band,which are composed of S 3p and Zn 4s orbital,respectively.The surface structure of Zn-vacancy sphalerite is more stable than S-vacancy surface due to the occupation of Zn-vacancy by Cu atoms;hence,the substitution reaction of Cu for Zn vacancy is easier than the substitution of Cu for Zn atoms with S-vacancy surface. 展开更多
关键词 SPHALERITE vacancy defect Density Functional Theory calculations copper activation
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Bioleaching of Zn(Ⅱ) and Pb(Ⅱ) from Nigerian sphalerite and galena ores by mixed culture of acidophilic bacteria
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作者 Alafara A.BABA Folahan A.ADEKOLA +2 位作者 Rasaq F.ATATA Risikat N.AHMED Sandeep PANDA 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第11期2535-2541,共7页
Zn(Ⅱ) and Pb(Ⅱ) from Nigerian sphalerite and galena ores were bioleached by a mixed culture of acidophilic bacteria.The influences of pH and ferric ion on the bioleaching rates of sphalerite and galena were exam... Zn(Ⅱ) and Pb(Ⅱ) from Nigerian sphalerite and galena ores were bioleached by a mixed culture of acidophilic bacteria.The influences of pH and ferric ion on the bioleaching rates of sphalerite and galena were examined.The result shows that pH 2.1 and 2.7 are favourable for the leaching of Zn(Ⅱ) and Pb(Ⅱ) from sphalerite and galena,respectively.It was observed that the use of agarose-simulated media caused cells to excrete exopolymers containing ferric ions which enhanced oxidation.The oxidation equilibrium for sphalerite and galena took 3 and 4 d,respectively.About 38.3% sphalerite and 34.2% galena were leached within 1 d and approximately 92.0% Zn(Ⅱ) and 89.0% Pb(Ⅱ) were recovered in 5 d,respectively.The unleached residual products were examined by X-ray diffraction for sphalerite,revealing the presence of elemental sulphur(S),zinc sulphate(ZnSO4) and few traces of calcium aluminate(Ca3Al2O6).The XRD pattern also indicates the presence of elemental sulphur(S),lead sulphate(PbSO4) and few traces of itoite [Pb(S,Ge)(O,OH)4] and cobalt lead silicate [Pb8Co(Si2O7)3] in the unleached galena ore. 展开更多
关键词 SPHALERITE GALENA zinc(Ⅱ) lead(Ⅱ) oxidation acidophilic bacteria
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Bioleaching of marmatite using moderately thermophilic bacteria
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作者 周洪波 刘飞飞 +2 位作者 邹颖钦 曾晓希 邱冠周 《Journal of Central South University of Technology》 EI 2008年第5期650-655,共6页
The process of bioleaching marmatite using moderately thermophilic bacteria was studied by comparing marmatite leaching performance of mesophiles and moderate thermophiles and valuating the effect of venting capacity ... The process of bioleaching marmatite using moderately thermophilic bacteria was studied by comparing marmatite leaching performance of mesophiles and moderate thermophiles and valuating the effect of venting capacity as well as pulp density on marmatite leaching performance of moderate thermophiles. The results show that moderate thermophiles have more advantages over mesophilies in bioleaching marmatite at 45 ℃ and the pulp density of 50 g/L, and the zinc extraction efficiency reaches 93.1% in 20 d. Aeration agitation can improve the transfer of O2 and CO2 in solution and promote the growth of bacteria and therefore, enhance the leaching efficiency. Under the venting levels of 50, 200 and 800 mL/min, the zinc extraction efficiencies by moderate thermophiles are 57.8%, 92.5% and 96.0%, respectively. With the increase of pulp density, the total leaching amount of valuable metals increases, however, the extraction efficiency decreases due to many reasons, such as increasing shear force leading to poorly growth condition for bacteria, etc. The zinc extraction decreases remarkably to 58.9% while the pulp density mounts up 20%. 展开更多
关键词 MARMATITE moderate thermophilies ZINC BIOLEACHING
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Electronic Structure and Optical Properties of Zinc-Blende In_xGa_(1-x)N_yAs_(1-y) by a First-Principles Study
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作者 沈阅 芦鹏飞 +4 位作者 俞重远 赵龙 叶寒 刘玉敏 袁桂芳 《Communications in Theoretical Physics》 SCIE CAS CSCD 2011年第4期693-701,共9页
Electronic structure and optical properties of the zinc-blende InxGa1-xNyAs1-y system are calculated from the first-principles. Some relative simulations are performed using CA-PZ form of local density approximation i... Electronic structure and optical properties of the zinc-blende InxGa1-xNyAs1-y system are calculated from the first-principles. Some relative simulations are performed using CA-PZ form of local density approximation in the framework of density functional theory. The supercell of intrinsic GaAs is calculated and optimized by using different methods, and the LDA-CA-PZ gives the most stable structure. The band gap of InzGa1-x As tends to decrease with the increasing In concentration. For the case of In0.0625Ga0.9375NyAs1-y, the band gap will show slight difference when N concentration is larger than 18. 75~. The optical transition of In dopant in GaAs exhibits a red shift, while it is a blue shift for the N dopant in InGaAs. Besides, dielectric function, reflectivity, refractive index and loss function in different doping model of InxGa1-xNyAs1-y are also discussed. 展开更多
关键词 first-principles calculation GAAS electronic structure optical properties
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A primary study of simultaneous leaching of silver containing manganese ore and a sphalerite concentrate 被引量:2
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作者 Li Zhizhang Li Yanjun 《Engineering Sciences》 EI 2008年第3期90-92,共3页
It is demonstrated that a low grade, silver containing manganese deposit can be exploited by reaction with a ZnS concentrate. In the process, Mn(IV) is reduced to Mn(II) and the ZnS converted to ZnSO4. In the process,... It is demonstrated that a low grade, silver containing manganese deposit can be exploited by reaction with a ZnS concentrate. In the process, Mn(IV) is reduced to Mn(II) and the ZnS converted to ZnSO4. In the process, Mn and Zn are solubilized. By studying the effects of quantity of reducing agent and sulfuric acid added and of time, temperature and liquid-to-solid ratio on the leaching process, the optimum technological conditions have been achieved under which the amount of manganese leached was 98 %. The silver can be removed from remaining solids by adding ammonia liquor. Then by adding hydrazine hydrate, sponge silver with purity up to 99 % can be obtained with a recovery of 87 %. 展开更多
关键词 SILVER MANGANESE SPHALERITE reduction LEACHING
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Structure and quality controlled growth of InAs nanowires through catalyst engineering 被引量:4
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作者 ZhiZhang Zhenyu Lu +3 位作者 Hongyi Xu Pingping Chen Wei Lu Jin Zou 《Nano Research》 SCIE EI CAS CSCD 2014年第11期1640-1649,共10页
In this study, the structure and quality controlled growth of InAs nanowires using Au catalysts in a molecular beam epitaxy reactor is presented. By tuning the indium concentration in the catalyst, defect-free wurtzit... In this study, the structure and quality controlled growth of InAs nanowires using Au catalysts in a molecular beam epitaxy reactor is presented. By tuning the indium concentration in the catalyst, defect-free wurtzite structure and defect-free zinc blende structure InAs nanowires can be induced. It is found that these defect-free zinc blende structure InAs nanowires grow along 〈110〉 directions with four low-energy {111} and two {110} side-wall facets and adopt the (111) catalyst/nanowire interface. Our structural and chemical characterization and calculations identify the existence of a catalyst supersaturation threshold for the InAs nanowire growth. When the In concentration in the catalyst is sufficiently high, defect-free zinc blende structure InAs nanowires can be induced. This study provides an insight into the manipulation of crystal structure and structure quality of III-V semiconductor nanowires through catalyst engineering. 展开更多
关键词 STRUCTURE QUALITY InAs nanowires molecular beam epitaxy (MBE) Au catalysts
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Catalyst-Free Synthesis and Shape Control of CdTe Nanowires 被引量:2
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作者 Xiaoping Jin Marta Kruszynska Jurgen Parisi Joanna Kolny-Olesiak 《Nano Research》 SCIE EI CAS CSCD 2011年第9期824-835,共12页
The procedure reported here allows for the size and shape control of CdTe nanowires by means of colloidal chemistry. Thus, ultrathin, straight, saw-tooth-like and one-sided branched nanowires with zinc blende structur... The procedure reported here allows for the size and shape control of CdTe nanowires by means of colloidal chemistry. Thus, ultrathin, straight, saw-tooth-like and one-sided branched nanowires with zinc blende structures could be synthesized. Their formation does not require any catalyst and is most likely due to the oriented attachment of nanoparticles formed in the beginning of the reaction. The use of oleylamine as a solvent turned out to be crucial in order to achieve CdTe nanowires. The reaction between oleic acid and oleylamine in the presence of CdO proved to be essential, not only to activate the Cd precursor but also to provide reaction conditions facilitating nanowire formation by oriented attachment. 展开更多
关键词 NANOWIRES CDTE amine activation oriented attachment shape control
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