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Control of redox potential by oxygen limitation in selective bioleaching of chalcocite and pyrite

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Rare Metals 2014年第5期33卷 622-627页

作者： Biao Wu Jian-Kang Wen Bo-Wei Chen Guo-Cheng Yao dian-zuo wang National Engineering Laboratory of Biohydrometallurgy General Research Institute for Nonferrous Metals

Based on the bioleaching mechanism and electrochemical studies of metal sulfides, the dissolution rates of chalcocite and pyrite are controlled by redox potentials. Experiment on the bioleaching of chalcocite and pyrite under constant redox potential by sparging with nitrogen gas was demonstrated. By leaching at low and constant redox potential（〈760 mV, vs SHE）, copper recoveries of 90 %–98 % are achieved, which are 10 times more than iron recoveries. The iron-oxidizing bacterial populations are observed to continue to reduce under oxygen limitation conditions, but the Acidithiobacillus that have only sulfur-oxidizing capabilities are an attractive alternative for redox-controlled bioleaching of ***, the described redox control technique might be one of the effective approaches to balance acid and iron in Zijinshan copper bio-heap leaching practice.

关键词： Pyrite Chalcocite Bioleaching Redox potential Oxygen limitation

Mechanism of aluminum complexation in oxidative activity of leaching bacteria in a fluoride-containing bioleaching system

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Rare Metals 2019年第1期38卷 87-94页

作者： Xiang Li Jian-Kang Wen Xiao-Lan Mo Wu Biao dian-zuo wang Hong-Ying Yang National Engineering Laboratory of Biohydrometallurgy General Research Institute for Nonferrous Metals School of Metallurgy Northeastern University

Accumulation of toxic ions in leachate is one factor limiting bioleaching applications. The effect of fluoride ions on the growth of bioleaching microorganisms has been extensively emphasized. In this study, HF is found to be the toxic form of fluoride that affects the bacterial activity under acidic conditions. The added aluminum could compete with H^+ to complex with F-, thus significantly decrease the concentration of HF and finally reduce the toxicity of fluoride to bacteria. When F^-/Al^(3+)concentration ratio is 0.5:1.0, Fe^(2+) oxidation rate could reach 0.167 g·L^(-1)·h^(-1), close to that of the biotic control group(0.195 g·L^(-1)·h^(-1)). The competitive complexation mechanism of fluoride by AlF_n^(3-n) results in stability constants of AlF_n^(3-n) complex(7.00) that are larger than those of HF(3.18). The F^-/Al^(3+) concentration ratio in the medium could affect the speciation of AlF_n^(3-n) *** the decrease in F^-/Al^(3+) concentration ratio, the coordination numbers of AlF_n^(3-n) decrease. Finally, the feasibility of fluoride detoxification by aluminum ion is verified. This work has meaningful implications for fluoride-containing bacterial bioleaching systems.

关键词： Competitive complexation Detoxification Fluoride Aluminum Bioleaching

Surface Modification Mechanism of Fine Coal by Electrochemical Methods

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Journal of China University of Mining and Technology 2006年第2期16卷 180-183页

作者： ZHU Hong wang Fang-hui wang dian-zuo OU Ze-shen School of Science Beijing Jiaotong University Beijing 100044 China Beijing General Research for Non-Ferrous Metals Beijing 100088 China School of Chemical Engineering and Environment China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China

In order to reveal the surface modification mechanism of fine coal by electrochemical methods, the structural changes of the coal surface before and after electrochemical modification were investigated by Fourier Transform In- frared Spectra (FTIR) and Raman Spectra. The results show that under certain electrochemical conditions, the oxy- gen-containing functional group in the coal structure and the oxygen content of absorption could be reduced and the floatability of coal improved. At the same time, the sulfur in the coal was reduced to the hydrophilic S2– which could be separated easily from coal. Thus electrochemical modification methods could be used to change the structure and func- tional group on the coal surface and to enhance the floatability of coal.

关键词： fine coal electrochemistry modification modification mechanism FTIR Raman Spectra

Measurement on soil deformation caused by expanded-base pile in transparent soil using particle image velocimetry (PIV)

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Journal of Mountain Science 2017年第8期14卷 1655-1665页

作者： QI Chang-guang ZHENG Jin-hui zuo dian-jun CHEN Geng Faculty of Architectural Civil Engineering and EnvironmentNingbo University Tianjin Research Institute for Water Transport Engineering M.O.T. Geotechnical Research Institute Hohai University

A new small-scale geotechnical physical model in 1-g and unconfined condition, combining the transparent soil, close-range photogrammetry and particle image velocimetry(PIV), was employed, which provides a non-intrusively internal deformation measurement approach to monitor the internal deformation of soil caused by expanded-base pile jacking with casing. The transparent soil was made of fused quartz and its refractive index matched blended oil, adding reflective particles(glass beads). Closerange photogrammetry was employed to record the images of the process of casing jacking and extraction in transparent soil, allowing the use of Matlab-based Geo-PIV to figure out the displacement field converted from image space to object space. Analysis of test results indicates that the maximum displacement caused by casing jacking for expandedconical-base pile is decreased by 29% compared with that for expanded-flat-base pile. The main movement happens at the early stage of casing extraction. The maximum displacement caused by casing extraction for the conical base is about 43% of that for the flatbase, while the affected zone caused by casing extraction for the conical base accounts for about 1/3 of that for the flat base. The contraction for horizontal displacements tends to decrease with the depth increasing. By contrast, the contraction under pile base decreases with the increasing of displacement. The displacements generated by jacking a conventional pile having a diameter equal to the casing diameter of the expanded-base pile were comparable to the net displacement taking place due to expanded-base pile installation for the conical base pile.

关键词： Geotechnical physical model Expanded-base pile Transparent soil Particle image velocimetry(PIV) Close-range photogrammetry

A novel method for preparation of tissue microarray

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World Journal of Gastroenterology 2004年第4期10卷 579-582页

作者： Han-LeiDan Ya-LiZhang YanZhang Ya-Dongwang zuo-ShengLai Yu-JieYang Hai-HongCui Yan-TingJian JianGeng Yan-QingDing Chun-HaiGuo dian-YuanZhou InstituteofDigestiveMedicine NanfangHospitalFirstMilitaryMedicalUniversityGuangzhou510515GuangdongProvinceChina DepartmentofPathology NanfangHospitalFirstMilitaryMedicalUniversityGuangzhou510515GuangdongProvinceChina CenterDepartmentofChineseAcademyofEngineeringandPhysics Mianyang621000SichuanProvinceChina

AIM:To improve the technique of tissue microarray (tissue chip).METHODS: A new tissue microarraying method was invented with a common microscope installed with a special holing needle, a sampling needle, and a special box fixing paraffin blocks on the microscope slide carrier. With the movement of microscope tube and objective stage on vertical and cross dimensions respectively, the holing procedure on the recipient paraffin blocks and sampling procedure of core tissue biopsies taken from the donor blocks were performed with the refitted microscope on the same *** precise observation and localization of representative regions in the donor blocks were also performed with the microscope equipped with a ***: Highly-qualified tissue chips of colorectal tumors were produced by a new method, which simplified the conventional microarraying procedure, and was more convenient and accurate than that employing the existing tissue microarraying ***:Using the refitted common microscope to produce tissue microarray is a simple, reliable, cost-effective and well-applicable technique.

关键词：组织微阵列技术组织芯片显微镜样本处理实验医学

Ethyl pyruvate protects against experimental acute-on-chronic liver failure in rats

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World Journal of Gastroenterology 2012年第40期18卷 5709-5718页

作者： Lu-Wen wang Li-Kun wang Hui Chen Cheng Fan Xun Li Can-Ming He zuo-Jiong Gong Department of Infectious Diseases Renmin Hospital of Wuhan University Wuhan 430060 Hubei Province China Institute of Infectious Diseases Hubei Center for Disease Control and Prevention Wuhan 430079 Hubei Prov- ince China

AIM： To investigate the protective effects of ethyl py- ruvate （EP） on acute-on-chronic liver failure （ACLF） in rats. METHODS： An ACLF model was established in rats, and animals were randomly divided into normal, mod- el and EP treatment groups. The rats in EP treatment group received EP （40 mg/kg） at 3 h, 6 h, 12 h and 24 h after induction of ACLF. Serum endotoxin, high mobility group box-1 （HMGB1）, alanine transaminase （ALT）, tumor necrosis factor-α （TNF-α）, interferon-α （IFN-γ）, interleukin （IL）-10 and IL-18 levels, changes of liver histology and HMGB1 expressions in liver tis- sues were detected at 48 h after induction of ACLF. The effects of EP on the survival of ACLF rats were also ***： Serum levels of endotoxin （0.394 ± 0.066 EU/mL vs 0.086±0.017 EU/mL, P 〈 0.001）, HMGB1 （35.42±10,86 μg/L vs 2.14 ± 0.27 μg/L, P 〈 0.001）, ALT （8415.87 ± 3567.54 IU/L vs 38.64 ± 8.82 IU/L, P 〈 0.001）, TNF-α （190.77 ± 12.34 ng/L vs 124.40 ± 4.12 ng/L, P 〈 0.001）, IFN-γ （715.38 ± 86.03 ng/L vs 398.66 ± 32.91 ng/L, P 〈 0.001）, IL-10 （6.85 ± 0.64 ng/L vs 3.49 ± 0.24 ng/L, P 〈 0.001） and IL-18 （85.19 ±3.49 ng/L vs 55.38 ±1.25 ng/L, P 〈 0.001） were significantly increased, and liver tissues presented se- vere pathological injury in the model group compared with the normal group, Howeverr EP administration significantly improved hepatic histopathology and re- duced the serum levels of endotoxin （0.155±0.045 EU/mL vs 0.394 ± 0.066 EU/mL vs P 〈 0.001） and in- flammatory cytokines （11.13 ± 2.58 μg/L vs 35.42 ± 10.86 μg/L for HMGB1, 3512.86 ± 972.67 IU/L vs 8415.87 ± 3567.54 IU/L for ALT, 128.55 ± 5.76 ng/L vs 190.77 ± 12.34 ng/L for TNF-α 438.16 ± 38.10 ng/L vs 715.38 ± 86.03 ng/L for IFN-γ 3.55 ± 0.36 ng/L vs 6.85 ± 0.64 ng/L for IL-10, and 60.35 ± 1.63 ng/L vs 85.19 ± 3.49 ng/L for IL-18, respectively, P 〈 0.001）, and the levels of HMGB1 in liver tissues re- gardless of treatment time after induction of ACLF. EP treatment at the four time points prolonged the me- dian survi

关键词： Acute-on-chronic liver failure Ethyl pyru-vate High mobility group box-1 Inflammatory cyto-kines Histopathology Survival time

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矿物加工方法应用新领域——污染土壤的治理

矿冶工程 2001年第1期21卷 1-3页

作者：陈泉源张泾生王淀佐长沙矿冶研究院湖南长沙410012 北京有色金属研究总院北京100044

随着社会、经济的发展 ,矿物加工方法的应用领域在不断扩大 ,污染土壤的治理已经成为矿物加工研究工作者关注的课题。污染土壤的治理方法、单元作业、工艺流程等与矿物加工过程中采用的工艺类似 ,运用矿物加工方法对土壤进行治理 ,将部... 详细信息

随着社会、经济的发展 ,矿物加工方法的应用领域在不断扩大 ,污染土壤的治理已经成为矿物加工研究工作者关注的课题。污染土壤的治理方法、单元作业、工艺流程等与矿物加工过程中采用的工艺类似 ,运用矿物加工方法对土壤进行治理 ,将部分弥补耕地的不足 ,保护生态环境 ,缓解人口。

关键词：矿物加工土壤污染环境治理

不同嵌固深度排桩受力与变形特性现场试验研究

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岩土工程学报 2014年第S2期36卷 354-359页

作者：左殿军邓成发交通运输部天津水运工程科学研究所岩土工程研究中心天津300456 河海大学岩土工程科学研究所江苏南京210098 浙江省水利河口研究院岩土工程研究所浙江杭州310020

根据某一水闸基坑开挖工程,在排桩桩体内埋设测斜仪、钢筋应力计对非等长双排桩基坑支护结构变形特性进行了现场观测,采用规范法讨论了后排桩不同嵌固对前、后排桩的变形、内力影响。研究结果表明:非等长双排桩桩顶位移、桩身剪力、弯... 详细信息

根据某一水闸基坑开挖工程,在排桩桩体内埋设测斜仪、钢筋应力计对非等长双排桩基坑支护结构变形特性进行了现场观测,采用规范法讨论了后排桩不同嵌固对前、后排桩的变形、内力影响。研究结果表明:非等长双排桩桩顶位移、桩身剪力、弯矩与传统等长双排桩基坑支护结构规律一致;增大后排桩的嵌固深度,前、后排桩的桩顶位移均减小;前排桩桩身剪力、弯矩减小,后排桩增大,但当嵌固深度超过桩长3/4时,前、后排桩的桩顶水平位移、桩身剪力、弯矩减小或增大趋势均不明显;研究成果为双排桩基坑支护结构设计优化提供一定参考。

关键词：嵌固深度双排桩支护结构变形特性现场试验

吸收光谱法在垃圾渗滤液膜处理技术中的应用研究

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光谱学与光谱分析 2006年第8期26卷 1449-1453页

作者：张宏忠方少明松全元王淀佐郑州轻工业学院材料与化工学院河南郑州450002 北京科技大学土木与环境工程学院北京100083 中国工程院北京100038

用可见-紫外光谱法测定了北神树垃圾填埋场渗滤液及各种膜出水中有机物的分子量分布,其中芳香化合物以分子量小于2 500的为主,而总体有机物随分子量的分布比较分散。测定了膜对不同分子量有机物的去除率。提出了一种可以直接用于垃圾渗... 详细信息

用可见-紫外光谱法测定了北神树垃圾填埋场渗滤液及各种膜出水中有机物的分子量分布,其中芳香化合物以分子量小于2 500的为主,而总体有机物随分子量的分布比较分散。测定了膜对不同分子量有机物的去除率。提出了一种可以直接用于垃圾渗滤液红外光谱法测定的制样新方法。根据各种膜出水的三处红外特征吸收峰发生的变化,说明了各种膜都能去除不同分子量和类型的腐殖质,并且估算了垃圾渗滤液中的腐殖质、石油类和动植物油经各种膜过滤后的去除率。

关键词：吸收光谱可见-紫外光谱傅里叶变换红外光谱垃圾渗滤液有机物膜处理