金属毒性研究（Ⅰ）

采用体外细胞培养模式,通过测定细胞碱式磷酸酶（ALP）活性及细胞四甲基偶氮砜（MTT）还原能力,对构成金属和合金生物材料的金属离子（Al,Ni,Cr,V,Ag)的毒性进行了定量评估,探讨了金属离子或原子对人体组织的毒害和腐蚀作用,结果表明微量六价铬离子表现出强烈的细胞毒性,当溶液离子度高于100umol/L时,钒和镍亦表现强烈毒性,银离子和三价铬离子浓度高于500umol/L后表现毒性,构成老年痴呆病成因的金属铝离子的毒性具有双向性。     

Cr（Ⅵ）-柠檬酸-硝酸铁复合体系中光催化还原Cr（Ⅵ）

利用高能球磨法制备了钙钛矿型硫酸盐掺杂的含钛高炉渣光催化剂,考察了初始pH值对Cr(Ⅵ)-柠檬酸-硝酸铁(Cr(Ⅵ)-CA-FN)复合体系中Cr(Ⅵ)吸附效率和光催化还原效率的影响,并探讨了Cr(Ⅵ)-CA-FN复合体系中Cr(Ⅵ)可能的光催化还原机理.结果表明:在Cr(Ⅵ)-CA-FN复合体系中,酸性条件下有利于Cr(Ⅵ)的光催化还原,最佳pH值为2.5;柠檬酸和Fe(Ⅲ)降低了吸附对Cr(Ⅵ)还原率的影响,有效地抑制电子-空穴对的复合,促进光生电子还原Cr(Ⅵ)离子;六价铬浓度的降低一部分是光催化还原所致,另一部分是由于催化剂本身含有的二价锰离子还原所致.     

好氧条件下铬污染土壤中Cr(Ⅵ)的土著微生物还原（英文）

生物修复是一种环境友好型的修复技术,在铬污染土壤修复中发挥着越来越重要的作用。为了研究土著微生物对土壤中Cr(Ⅵ)的还原过程,在生物反应器里进行一系列微生物好氧培养实验。结果显示:在土著微生物存在情况下,在铬污染土壤中添加培养基使Cr(Ⅵ)浓度在66h内从1521.9降低至199.2mg/kg,而灭菌土壤中Cr(Ⅵ)浓度稍微降低,表明Cr(Ⅵ)的还原归因于土著微生物的作用。在微生物修复过程中,Cr(Ⅵ)的生物还原发生在NO_3~-、Mn~(4+)和Fe~(3+)的还原后,而先于SO_4~(2-)的还原。Cr(Ⅵ)还原过程可分为两个阶段,分别以生物还原作用的指数方程模型和主要离子综合效应的线性方程模型为特征。土著Cr(Ⅵ)还原菌在Cr(Ⅵ)污染土壤的原位修复中具有潜在的应用前景。     

医用金属材料离子释放机制、致病机理及防护

结合近年来国内外医用钛合金等金属材料在生物体和人体临床应用研究成果,研究了人体植入物等医用金属材料中Ni、Al、V等有害离子的释放机制、致病机理及防护(涂层)方法。系统分析了常用医用金属材料Ti6Al4V和Ti Ni形状记忆合金等钛合金在腐蚀等作用下有害离子的释放机制,有害离子及其形成化合物对人体的毒性作用,和常用表面改性技术制备涂层对于有害离子的抑制和防护作用。研究结果表明,近年来发展起来的表面改性技术显著提高钛合金耐蚀性,可以有效抑制有害离子的释放,提高钛合金的生物相容性。     

腐殖质AQS存在条件下腐败希瓦氏菌还原U(Ⅵ)的特性

在厌氧条件下,研究腐败希瓦氏菌还原U(Ⅵ)的特性,考察腐殖质模式物蒽醌2磺酸钠(AQS)浓度、金属离子(Cu2+、Ca2+、Cr6+等)与有毒有机物等对U(Ⅵ)还原的影响。结果表明:腐败希瓦氏菌可以利用一些有机酸盐作为电子供体,以AQS作为电子穿梭载体,进行醌呼吸,高效还原U(Ⅵ)。当AQS的浓度为0~2 mmol/L时,能显著加速U(Ⅵ)的还原过程;当AQS的浓度高于2 mmol/L时,随着AQS浓度从2 mol/L增加到10 mol/L,AQS与U(Ⅵ)竞争电子,明显抑制U(Ⅵ)的还原。同时,Ca2+和Cu2+对U(Ⅵ)的还原均表现出较强的抑制作用,Cu2+的抑制作用通过抑制呼吸链上脱氢酶的活性实现;但Mn2+和Cr6+对腐殖质还原U(Ⅵ)的影响较小,在60 h内,未观测到溶液中Cr6+浓度的明显变化。金属离子对还原U(Ⅵ)抑制作用的强度与其浓度正相关。环境中甲苯、三氯乙酸和对硝基苯酚等有毒有机物可以作为电子供体被腐败希瓦氏菌利用而降解,得到氧化降解,同时实现U(Ⅵ)的高效还原。     

微合金化对铝钢合金金属间化合物的第一性原理研究

材料的电子态密度对材料的导热及原子之间化学键连接具有重要的影响,文中采用基于密度泛函理论的第一性原理平面波赝势法,计算了合金元素(Cr,Mn,Mo,Ni,Ti,V和Zn)的掺杂对FeAl3电子特性的影响,以及Fel2Al39,(Fe10X2)Al39(X=Cr,Cu,Mg,Mn,Mo,Ni,Si,Ti,V,Zn)和Fe...     

Pannonibacter phragmitetus对Cr(Ⅵ)污染土壤的修复效应

在前期从铬渣污染土壤中分离筛选出高效还原Cr(Ⅵ)的土著微生物(Pannonibacter phragmitetus)的基础上,通过单因素实验对所筛选的土著微生物修复模拟铬污染土壤效应及其影响因素进行研究.结果表明: 土著微生物对土壤中Cr(Ⅵ)的修复受pH值、微生物接种量和初始Cr(Ⅵ)浓度的影响;pH值越高、微生物接种量越大而初始Cr(Ⅵ)浓度越低时,Cr(Ⅵ)的修复速率越快;所筛选的土著微生物在316 h内就能够完全还原污染土壤中浓度为360 mg/kg的Cr(Ⅵ);Cr(Ⅵ)的修复是土著微生物(Pannonibacter phragmitetus)通过酶促反应对Cr(Ⅵ)的直接还原所致.     

熔盐电解制备铝钕中间合金及其机理

以Na_3AlF_6-AlF_3-MgF_2-LiF为电解质,Al_2O_3、Nd_2O_3为原料,对熔盐电解制备Al-Nd中间合金进行研究;采用扫描电子显微镜(SEM)、能谱(EDS)分析合金产物的形貌及组成;通过还原实验和循环伏安法,对Nd(Ⅲ)离子在Na_3AlF_6-AlF_3-MgF_2-LiF体系中的还原过程进行表征。结果表明:在温度935℃、恒压3.2 V条件下,通过Na_3AlF_6-AlF_3-MgF_2-LiF-(Al_2O_3、Nd_2O_3)体系可电解得到Al-Nd中间合金,富钕相集中分布在铝基体晶界区域,Nd(Ⅲ)离子主要通过铝热还原形式进入合金相,且Nd_2O_3的加入可起到去极化作用,使Al(Ⅲ)离子扩散系数大幅提高。     

TiAl/40Cr高频感应钎焊接头的界面组织及力学性能

以Ag-Cu-Ni-Li为钎料对TiAl与40Cr进行了高频感应钎焊,研究了TiAl/40Cr钎焊接头的界面组织和力学性能.采用扫描电镜、电子探针、X射线能谱分析仪等分析了界面组织及生成相,测试了接头的抗拉强度及界面生成相的显微硬度.结果表明:钎料与2种母材发生界面生反应成Al3Ti、Ag[s,s]、Ti(CuAl) 2、Ti2Ni和TiC等多种反应相,接头界面结构Al/A为Til3Ti/Al3Ti十Ag[s,s]/Ti(CuAl)2 Ti2Ni Ag[s,s]/TiC/40Cr.在实验所选的工艺参数范围内,当连接温度θ=850℃,保温时间t=180 s时,接头的抗拉强度达到265 MPa.     

Al2O3和Cr过渡层对Ag膜光学性质及其附着力的影响

研究了在玻璃基底上镀制Al2O3和Cr过渡层对Ag膜反射率及附着力的影响.分光光度计测试了Ag膜的反射率,结果表明,与Cr过渡层相比,Al2O3过渡层对Ag膜反射率的降低相对较小;而且,随着Al2O3厚度的增加,Ag膜的反射率先增大后减小.XRD与AES测试表明,引入Al2O3或Cr可明显细化Ag晶粒,减弱Ag膜(111)织构;Al2O3作过渡层时,Al原子向Ag层中扩散显著;而Cr作过渡层时,只有少量Cr原子扩散进入Ag层.因此,Al2O3作过渡层能显著增强薄膜与玻璃基体之间的附着力.     

Three-Dimensional Growth of Coherent Ferrite in Austenite: A Molecular Dynamics Study

Coherent second phase often exhibits anisotropic morphology with specifi c orientations with respect to both the second and the matrix phases. As a key feature of microstructure, the morphology of the coherent particles is essential for understanding the second-phase strengthening eff ect in various industrial alloys. This letter reports anisotropic growth of coherent ferrite from austenite matrix in pure iron based on molecular dynamics simulation. We found that the ferrite grain tends to grow into an elongated plate-like shape, independent of its initial confi guration. The fi nal shape of the ferrite is closely related to the misfi t between the two phases, with the longest direction and the broad facet of the plate being, respectively, consistent with the best matching direction and the best matching plane calculated via the Burgers vector content(BVC) method. The strain energy calculation in the framework of Eshelby's inclusion theory verifi es that the simulated orientation of the coherent ferrite is energetically favorable. It is anticipated that the BVC method will be applicable in analysis of anisotropic growth and morphology of coherent second phase in other phase transformation systems.     

Effect of Short-Time Aging on the Pitting Corrosion Behavior of a Novel Lean Duplex Stainless Steel 2002

The effect of short-time aging in the temperature range between 400 and 1000 °C on the pitting corrosion behavior and mechanical property of a novel lean duplex stainless steel(LDSS) 2002 was investigated through the potentiostatic critical pitting temperature(CPT) tests and the Charpy impact tests. Both the pitting corrosion resistance and the toughness of aged specimens degraded due to the precipitation of detrimental secondary phases and the most significant reduction of CPT and impact energy emerged at 650 °C concurrently. The CPT of LDSS 2002 specimen aged at 650 °C decreased by 28 °C, and the impact energy dropped from 69 to 29 J/cm~2 compared with the solution-annealed sample. Transmission electron microscopy characterization showed that the main precipitates in LDSS 2002 were Cr_2N and M_(23)C_6 along the ferrite–austenite grain boundaries.     

INTRODUCTION TO PATENTS

The invention provides a method of making a mold which can reduce SOx generation rate while preventing decrease in hardening rate in the case of using sulfuric acid for a hardener composition. The method has a mixture step in which fire-resistant particles, a hardener composition and a binder composition are mixed to obtain a composition for a mold. The hardener composition contains sulfuric acid. In the mixture step, sodium carbonate is added. A molar ratio of the sulfuric acid to the sodium carbonate is 0.5 or more and 4.0 or less.     

China Foundry Week 2014

China Foundry Week, hosted by the Foundry Institution of Chinese Mechanical Engineering Society （FICMES） each year, is a large academic event in China. It is one of the ten high-impact activities sponsored by the Chinese Mechanical Engineering Society.     

17th Conference of Hydrodynamic and Electromechanical Control Engineering Call for papers

正1.Contents In order to promote the academic exchanges and technical communication of the research in the field of fluid power transmission and control,fluid control engineering specialized committee of the Chinese Society of Theoretical and Applied Mechanics will hold the 17th Conference of Hydrodynamic and Electromechanical Control Engineering on July 27-29,2014 in Tibet,Lhasa city.     

Information for Contributors

正The Transactions of Nonferrous Metals Society of China,founded in 1991 and sponsored by The Nonferrous Metals Society of China,is published monthly now and mainly contains reports of original research which reflect the new progresses in the field of nonferrous metals science and technology,including mineral processing,extraction metallurgy,metallic materials and heat treatments,metal working,physical metallurgy,powder metallurgy,with the emphasis     

Preface

<正>We are pleased to present this Special Issue of Transactions of Nonferrous Metals Society of China containing selected papers from the First Asian Conference on Aluminum Alloys(ACAA-2013),held in Beijing,China,13–17 October 2013.This conference has been initiated,with approval of     

Information for Contributors

The Transactions of Nonferrous Metals Society of China, founded in 1991 and sponsored by The Nonferrous Metals Society of China, is published monthly now and mainly contains reports of original research which reflect the new progresses in the field of nonferrous metals science and technology, including mineral processing, extraction metallurgy, metallic materials and heat treatments, metal working, physical metallurgy, powder metallurgy, with the emphasis on fundamental science. It is the unique preeminent publication in English for scientists, engineers, under/post-graduates on the field of nonferrous metals industry. This journal is covered by many famous abstract/index systems and databases such as SCI Expanded, Ei Compendex Plus, 1NSPEC, CA, METADEX, AJ and JICST.     

FORMULAS OF TENSION OF CONTINUOUS ROLLING PROCESS

The development of computer controlled continuous rolling process calls for a mathematical expression that can express the inequality condition of "constant flow". Tension is the link of the continuous rolling process. From the condition of dynamic equilibrium, a differential equation of tension is given out. On the basis of the physical rules established from the industrial practice and experimental studies, the law of volume constancy, the linear relation of forward slip and tension, the state equation of continuous rolling, the formula of dynamic tension, and the formula of static tension have been obtained. These formulae reflect the functional relations between tensions, thickness, roll velocity, and time in the continuous rolling process. It is implied that the continuous rolling process is a gradually steady, controllable, and measurable dynamic system. An assumption of predicting the thickness of a steel plate using these tension formulae is also put forward.     

A Concordant Shift Model for Flow in Bulk Metallic Glasses

The homogeneous plastic flow in bulk metallic glasses(BMGs) must be elucidated by an appropriate atomistic mechanism. It is proposed that a so-called concordant shifting model, based on rearrangements of five-atom subclusters,can describe the plastic strain behaviour of BMGs in a temperature range from room temperature to the supercooled liquid region. To confirm the effectiveness of the atomic concordant shifting model, a comparative investigation between the vacancy/atom model and the concordant shifting model is carried out based on the estimation of the strain rate deduced from two models. Our findings suggest that the atomic concordant shifting model rather than the vacancy/atom exchange model can well predict the large strain rate in the superplasticity of BMGs.