材料期刊网

本地混合菌群微生物氧化难处理含金硫化精矿

M. M. BARROSO QUIROGA , A. GIAVENO , E. DONATI

中国有色金属学报(英文版) doi:10.1016/S1003-6326(17)60133-X

采用含铁氧化菌和硫氧化菌的混合嗜中温菌群浸出阿根廷Andacollo矿的含金硫化浮选精矿.实验在摇瓶中进行,矿浆浓度为10%,采用pH 1.8的含亚铁离子的基础盐溶液作为介质.采用不同的方法对浸出液的pH值、氧化还原电位、亚铁离子和总金属浓度进行测定.结果表明,该种混合菌能够很好地还原浸出该难处理金矿,金的回收率可达91.6%,同时,铜和锌的浸出率也较高.动力学研究表明金属的溶解符合收缩核模型.其中,铜的溶解速率受生成产物层的扩散控制,而锌的溶解没有明显的控制步骤.

关键词: 生物氧化 , 难处理金矿 , 混合菌 , 动力学分析

Semiconducting properties of passive film formed on stainless steel by using A. V. passivation

Acta Chimica Sinica

Passive film formed on 304 stainless steel in 2.5 mol/L H2SO4 solution by using alternating voltage (A. V.) passivation have been investigated by measuring capacitance and photoelectrochemical parameters. The investigation of the effect of measure frequency on the slope of Mott-Schottky curve has been carried out. The photoelectrochemical measurements were consistent with the capacitance measurement. Analysis of the experimental results showed that the passive film formed 304 stainless steel by using A. V. passivation exhibits semiconducting properties. Using the simple model of semiconductor rather than the multi-donor level model can explain satisfactorily the semiconducting behavior of the film formed on 304 stainless steel by using A.V. passivation.

关键词: A. V. passivation;passive film;semiconducting properties;stainless;steel;model;electrodes

EFFECT OF AN ELASTIC-PLASTIC SHOCK-WAVE .A. ON THE FATIGUE-STRENGTH OF WELDED-JOINTS

Fatigue & Fracture of Engineering Materials & Structures

Fatigue data for welded joints subjected to an explosion treatment (ET) were obtained using rotary bending fatigue specimens. The fatigue fracture surfaces were observed by SEM and the dislocation morphologies by TEM. Mechanical properties have been quantitively studied by considering elastic and plastic shock wave characteristics. The test results indicate that the fatigue strength of welded joints subjected to ET is apparently improved due to the action of elastic or plastic stress waves while the ductility of the welded joints, i.e., reduction in area, is greatly increased.

关键词:

Bi2-xPbxSr2Co2Oy单晶各向异性输运性质的研究

李慧玲 , 阮可青 , 王强 , 陈宇 , 钱朔 , 余勇 , 黄利 , 郑重 , 汪成友 , 曹烈兆

低温物理学报 doi:10.3969/j.issn.1000-3258.2003.04.007

研究了不同Pb含量的Bi2-xPbxSr2Co2Oy单晶的输运行为.用A. F. Ho 和A. J. Schofield提出的公式对ρc的温度依赖关系曲线进行了拟合,得到了较好的结果.我们利用小极化子理论解释了ρc的复杂行为.

关键词: 过渡金属氧化物的电导 , 小极化子

两步法制备Y_2O_3掺杂ZnO压敏瓷

徐东 , 巫欣欣 , 程晓农 , 张剑平 , 施利毅

材料导报

采用两步烧结制备了Y_2O_3掺杂ZnO压敏瓷,其电位梯度为863～1330V/mm,非线性系数为27.0～49.7,漏电流为0.55～1.13μA.研究结果表明,当Y_2C_3的掺杂量为1.00%(摩尔分数)时,压敏瓷电性能最好,电位梯度为1330V/mm,非线性系数为49.7,漏电流为0.76μA.

关键词: 压敏瓷 , 两步烧结 , 稀土 , 显微组织 , 电性能

Spectral density for the tunneling current zero-frequency shot-noise in a one-dimentional mesoscopic system

Acta Physica Sinica

We have derived the expression of the spectral density for the current shot-noise in terms of the nonequilibrium Green's functions( closed-path Green's functions) for a. one-dimensional mesoscopic junction, and performed numerical calculations to discuss the dependence of the zero frequency spectral density for the currentshot-noise on other variables when the tunnling junction is pure or impure.

关键词: electron-electron scattering;quantum-dot;transient transport;anderson;model;conductors;barrier;equilibrium;contacts

Fingerprint profiling of Astragalus polysaccharides based on partial acid hydrolysis-hydrophilic interaction chromatography analysis and comprehensive quality evaluation of Astragalus membranaceus combined with reversed-phase liquid chromatography fingerprint analysis

Hui WANG , Huaxia XIN , Jianfeng CAI , Fangbing LI , Yu JIN , Qing FU

色谱 doi:10.3724/SP.J.1123.2016.03006

Astragalus polysaccharides (APS) are important components in Astragalus membranaceus (A. membranaceus). However, for the huge relative molecular mass, strong polarity, and difficulty in chromatographic separation, there's a lack of quality control finely reflecting the composition of APS up to now. To solve the problems, the key lies in degradation of polysaccharides and analysis of the hydrolyzates. A partial acid hydrolysis-hydrophilic interaction liquid chromatography (HILIC) fingerprint for APS and a comprehensive quality evaluation method for A. membranaceus combining with the traditional RPLC fingerprint were developed. Orthogonal experiments were designed to investigate the influencing factors of partial hydrolysis and the conditions were optimized based on HILIC analysis. The hydrolyzates were successfully separated using HILIC-evaporative light scattering detection (ELSD) method and the optimal conditions of hydrolysis were selected as 80℃, 1.5 mol/L trifluoroacetic acid and 4 h, which proved to be stable and repeatable after the validation. This method was applied for the fingerprint analysis of 20 batches of A. membranaceus. Cosine method was used for similarity calculation using the average of samples Nos. 1-10 as reference. Moreover, RPLC fingerprint analysis was processed on other components and the data were compared for comprehensive evaluation. The similarities of ten samples with the reference ranged from 0.258 to 0.949, which were consistent with the chromatograms reflecting the apparent disparity in APS, and could be as a supplement of the RPLC fingerprint. The new method, with the advantages of intuition, convenience, and quantifiable in similarity, could reflect the differences of the composition of polysaccharides after degradation and was successfully applied in profiling of APS, contributing to the quality control together with the RPLC fingerprint.

关键词: partial acid hydrolysis , hydrophilic interaction liquid chromatography (HILIC) , Astragalus polysaccharides (APS) , fingerprint , quality evaluation

LX3032钢在炼厂冷换设备上的应用

任世科 , 骆重阳

腐蚀与防护

通过静态、动态腐蚀试验和现场应用试验,对新研制的LX3032无缝钢管在HCl-H2S-H2O环境中的腐蚀速率进行了测定.结果显示,与其他几种常用钢材相比,LX3032具有良好的耐腐蚀性能,能满足在HCL-H2S-H2O腐蚀环境下冷换设备的安全使用,腐蚀速率低于国标所限定的0.125mm/a.

关键词: 换热器 , 应力腐蚀 , 管束

TMEP作为缓冲层增加有机发光器件的效率的研究

李建丰 , 李勇华 , 孙硕 , 董茂军 , 欧谷平 , 张福甲

功能材料

在有机发光器件中的发光层和阴极之间插入了稳定性好、有良好电子传输能力的苝酸四甲酯(TMEP)新型缓冲层,改善了有机电致发光器件的亮度和发光效率.在电流密度为200mA/cm2时,有缓冲层的器件B效率为0.82cd/A,没有缓冲层的器件A效率为0.14cd/A.

关键词: 有机电致发光 , TMEP缓冲层 , 发光效率

08Cr19Ni9Mo4Cu4(Cw-1)耐磨蚀合金研究

杜辉 , 石巨岩 , 李春海 , 张猛

兵器材料科学与工程 doi:10.3969/j.issn.1004-244X.2005.03.012

Cw-1耐磨蚀合金是针对电厂脱硫系统介质工况而进行试验研究的.使用光学显微镜、万能材料试验机、磨蚀试验机等设备对材料的组织和力学性能做了测试和分析.结果表明,Cw-1合金具有很好的耐磨蚀性能、较高的强韧性和硬度、良好的工艺性能.此材料的磨蚀性能达到了耐蚀级,磨蚀率＜0.05 mm/a.

关键词: 耐磨蚀合金 , 组织 , 力学性能 , 耐磨蚀性能