Leaching behavior of butanedionedioxime as gold ligand

1　ＩＮＴＲＯＤＵＣＴＩＯＮＴｈｅｒｅａｒｅｔｗｏｔｙｐｅｓｏｆｏｒｂｉｔａｌｓｉｎｏｕｔｅｒｅｌｅｃｔｒｏｎｏｒｂｉｔａｌｓｏｆｇｏｌｄａｎｄｉｔｓｌｉｘｉｖｉａｎｔｓ[1,2 ] .ＯｎｅｉｓｃａｌｌｅｄＨＯＥＯ(ｈｉｇｈｅｒｏｃｃｕｐｉｅｄｅｌｅｃｔｒｏｎｉｃｏｒｂｉｔａｌｓ) ,ｓｕｃｈａｓπ ｔｙｐｅＨＯＥＯｏｆｂｏｔｈ 5ｄ2(ｘ2 -ｙ2 ) ａｎｄ 5ｄ2ｚｏｆｇｏｌｄ ,ａｎｄσ ｔｙｐｅＨＯＥＯｏｆσ22 ｐｘｏｆｃｙａｎｉｄｅ;ａｎｄａｎｏｔｈｅｒｃａｌｌｅｄＬＵＥＯ(ｌｏｗｅｒｕｎｏｃｃｕｐｉｅｄｅｌｅｃｔ…     

Phase equilibria and electrical properties of Nd2O3-SrO-TiO2 system

１ＩｎｔｒｏｄｕｃｔｉｏｎＩｎｃｏｎｎｅｃｔｉｏｎｗｉｔｈｏｕｒｒｅｓｅａｒｃｈｏｎｔｅｒｎａｒｙｃｏｍｐｏｕｎｄｕｓｅｄｆｏｒｄｉｅｌｅｃｔｒｉｃｍａｔｅｒｉａｌ,ｔｈｅｓｙｓｔｅｍｏｆＮｄ２Ｏ３ＳｒＯＴｉＯ２ｗａｓｉｎｖｅｓｔｉｇａｔｅｄ．ＯｔｈｅｒｔｈａｎｓｏｍｅｃｏｍｐｏｕｎｄｓｒｅｐｏｒｔｅｄｂｙＳｉｄｏｒｏｖａ［１］,ｔｈｉｓｓｙｓｔｅｍｈａｓｎｏｔｂｅｅｎｒｅｐｏｒｔｅｄｓｙｓｔｅｍａｔｉｃａｌｌｙ．Ｏｕｒｓｐｅｃｉａｌｉｎｔｅｒｅｓｔｆｏｃｕｓｅｄｏｎｔｈｅｐｒｏｂｌｅ…     

Molecular dynamics of structural properties of molten CaO-SiO2 with varying composition

1　ＩＮＴＲＯＤＵＣＴＩＯＮＴｈｅｓｔｕｄｙｏｆｍｏｌｔｅｎｓｔｒｕｃｔｕｒｅｏｆＣａＯ ＳｉＯ2 ,ｗｈｉｃｈａｃｔａｓｔｈｅｂａｓｉｃｆａｃｔｏｒｉｎｆｌｕｅｎｃｉｎｇｔｈｅｐｈｙｓｉｃａｌａｎｄｃｈｅｍｉｃａｌｐｒｏｐｅｒｔｉｅｓｏｆｔｈｅｓｉｌｉｃａｔ     

Simulation of droplet transfer process and current waveform control of CO_2 arc welding

1　ＩＮＴＲＯＤＵＣＴＩＯＮＣＯ2 ｓｈｉｅｌｄｅｄａｒｃｗｅｌｄｉｎｇｉｓｏｎｅｏｆｔｈｅｗｅｌｄｉｎｇｔｅｃｈｎｏｌｏｇｉｅｓｗｉｔｈｈｉｇｈｅｒｅｆｆｉｃｉｅｎｃｙ ,ｌｏｗｅｒｅｎｅｒｇｙｃｏｎｓｕｍｐｔｉｏｎ ,ｌｅｓｓｈｙｄｒｏｇｅｎｃｏｎｔｅｎｔａｎｄｈｉｇｈａｎｔｉ ｏｘ ｉｄａｔｉｏｎａｂｉｌｉｔｙ .Ｔｈｅｓｈｏｒｔ ｃｉｒｃｕｉｔｔｒａｎｓｆｅｒｉｓａｍａｉｎｆｏｒｍｉｎＣＯ2 ａｒｃｗｅｌｄｉｎｇｐｒｏｃｅｓｓ ,ｂｕｔｉｔｈａｓｔｏｏｍｕｃｈｓｐａｔｔｅｒｉｎｇ ,ａｎｄｕｎｓａｔｉｓｆ…     

Influence of size of seed grains and sintering condition on varistor properties of ZnO-Bi_2O_3-TiO_2-Sb_2O_3 ceramics

1　ＩＮＴＲＯＤＵＣＴＩＯＮＳｉｎｃｅＺｎＯｖａｒｉｓｔｏｒｃｅｒａｍｉｃｓｗｅｒｅｆｉｒｓｔｌｙｄｅｖｅｌ ｏｐｅｄｉｎ 196 8,ｓｉｇｎｉｆｉｃａｎｔｐｒｏｇｒｅｓｓｅｓｈａｖｅｂｅｅｎｍａｄｅｉｎｉｎｖｅｓｔｉｇａｔｉｏｎａｎｄａｐｐｌｉｃａｔｉｏｎｏｆｔｈｅｍａｔｅｒｉａｌ.Ａｓａｋｉｎｄｏｆａｄｖａｎｃｅｄｆｕｎｃｔｉｏｎａｌｃｅｒａｍｉｃｓ,ＺｎＯｖａｒｉｓｔｏｒｃｅｒａｍｉｃｓｈａｖｅｂｅｅｎｗｉｄｅｌｙｕｓｅｄｉｎｅｌｅｃｔｒｏｎｉｃｃｉｒｃｕｉｔｓａｎｄｅｌｅｃｔｒｉｃａｌｐｏｗｅｒ…     

Kinetic mechanism of anodic oxidation of tantalum in nitrate melts

1　ＩＮＴＲＯＤＵＣＴＩＯＮＴａｎｔａｌｕｍｃａｎｂｅｏｘｉｄｉｚｅｄａｔｌｏｗｔｅｍｐｅｒａｔｕｒｅｉｎ ｔｏｉｎａｃｔｉｖｅＴａ2 Ｏ5 ｗｉｔｈｃｏｍｐａｃｔｔｅｘｔｕｒｅａｎｄｓｐｅｃｉｆｉｃｒｅｓｉｓｔａｎｃｅｏｆ 1 0 18Ω·ｃｍ[1],ｗｈｉｃｈｅｎｔｉｔｌｅｓｔａｎｔａｌｕｍｇｏｏｄｃｏｒｒｏｓｉｏｎｒｅｓｉｓｔａｎｃｅａｎｄｅｌｅｃｔｒｉｃｒｅｓｉｓｔａｎｃｅ ,ａｎｄａｌｓｏｍａｋｅｓｉｔｉｍｐｏｓｓｉｂｌｅｔｏｇｅｔｔｈｉｃｋＴａ2 Ｏ5 ｆｉｌｍｓａｔｌｏｗｔｅｍｐｅｒａｔｕｒｅ .Ｔｈｅｏ…     

Study on electrochemical surface modification of coal by FTIR and Raman spectra

1　ＩＮＴＲＯＤＵＣＴＩＯＮＨｉｇｈｓｕｌｆｕｒｃｏａｌｏｃｃｕｐｉｅｓａｌａｒｇｅ ｐａｒｔｏｆｔｈｅｗｈｏｌｅｄｅｐｏｓｉｔｏｆｃｏａｌｉｎｔｈｅＳｏｕｔｈ ＷｅｓｔａｎｄｔｈｅＥａｓｔｏｆＣｈｉｎａ .Ｗｉｔｈｏｕｔｗａｓｈｉｎｇａｎｄｄｅｓｕｌｆｕｒｉｚａｔｉｎｇ ,ｔｈｅｃｏｍｍｅｒｃｉａｌｃｏａｌｉｓｏｆｌｏｗｑｕａｌｉｔｙ ,ｌｏｗｃｏｍｂｕｓｔｉｏｎｅｆ ｆｉｃｉｅｎｃｙｗｉｔｈｌａｒｇｅｃｏａｌｗａｓｔｉｎｇ ,ｇａｓａｓｈ ,ＣＯ2 ａｎｄＮＯｘ .Ａｂｏｖｅａｌｌ,ｔｈｅｃｏｍｂｕｓｔｉｏｎ…     

Carbonization kinetics of La_2O_3-Mo cathode materials

1　ＩＮＴＲＯＤＵＣＴＩＯＮＣａｒｂｏｎｉｚａｔｉｏｎｏｆｃａｔｈｏｄｅｉｓａｋｅｙ ｐｒｏｃｅｓｓｉｎＴｈＯ2 Ｗｃａｔｈｏｄｅｍａｎｕｆａｃｔｕｒｅ .ＷｈｅｎＴｈＯ2 Ｗｆｉｌａ ｍｅｎｔｓａｒｅｈｅａｔｅｄｉｎａｈｙｄｒｏｇｅｎａｔｍｏｓｐｈｅｒｅｃｏｎｓｉｓｔｉｎｇｏｆｂｅｎｚｅｎｅ ,ａｃｅｔｙｌｅｎｅ ,ｎａｐｈｔｈａｌｅｎｅｏｒｘｙｌｅｎｅｖａｐｏｒｓ ,ｔｈｅｈｙｄｒｏｃａｒｂｏｎｉｓｄｅｃｏｍｐｏｓｅｄａｔｔｈｅｈｏｔｆｉｌａｍｅｎｔｓｕｒｆａｃｅｔｏｆｏｒｍｄｉｔｕｎｇｓｔｅｎｃａｒｂ…     

Degradation characteristics of Ti/(IrO2+Ta2O5) coating anodes in H2SO4 solution

1　ＩＮＴＲＯＤＵＣＴＩＯＮＴｉｂａｓｅｄＩｒＯ2 ｃｏａｔｉｎｇａｎｏｄｅｓｗｅｒｅｗｉｌｄｌｙｕｓｅｄｉｎｅｌｅｃｔｒｏｃｈｅｍｉｃａｌｉｎｄｕｓｔｒｙｆｏｒｔｈｅｉｒｈｉｇｈｅｌｅｃｔｒｏｃａｔａｌｙｔｉｃａｃｔｉｖｉｔｙａｎｄｓｔａｂｉｌｉｔｙ[1] .Ｉｎａｎｅｘｔｒｅｍｅｃｏｎｄｉｔｉｏｎ ,ｓｕｃｈａｓｈｉｇｈ ｓｐｅｅｄｅｌｅｃｔｒｏｄｅｐｏｓｉｔｉｏｎ ,ｈｏｗｅｖｅｒ ,ｔｈｅｓｔａｂｉｌｉｔｙｏｆＩｒＯ2 ｉｓｎｏｌｏｎｇｅｒｓａｔｉｓｆｉｅｄ .Ｔｈｅｒｅｆｏｒｅ ,ｔｈｅｍｏｄｉｆｉｃａｔ…     

Recent development in researches of electrochemistry of sulphide flotation at Central South University of Technology

1　ＣＯＬＬＥＣＴＯＲＬＥＳＳＦＬＯＴＡＴＩＯＮ1.1　ＮａｔｕｒａｌｆｌｏａｔａｂｉｌｉｔｙＴｈｅｉｎｈｅｒｅｎｔｈｙｄｒｏｐｈｏｂｉｃｉｔｙｏｎｃｅｔｈｏｕｇｈｔｔｏｂｅｔｙｐｉｃａｌｏｆｓｕｌｆｉｄｅｓ[1] ｉｓｎｏｗｔｈｏｕｇｈｔｔｏｂｅｒｅｓｔｒｉｃｔｅｄｔｏｓｕｌｆｉｄｅｓｓｕｃｈａｓｍｏｌｙｂｄｅｎｉｔｅａｎｄｏｔｈｅｒｍｉｎｅｒａｌｓｏｒｃｏｍｐｏｕｎｄｗｉｔｈｓｐｅｃｉａｌｓｔｒｕｃｔｕｒａｌｆｅａｔｕｒｅｓ .Ｍｉｎｅｒａｌｓｓｕｃｈａｓｍｏｌｙｂｄｅｎｉｔｅ ,ｏｒｐｉｍｅｎｔ ,ｒｅ…     

变形程度对7A04合金半固态触变组织的影响

获得具有触变特性的均匀的、近球形的显微组织是半固态触变成形工艺的基础和关键。以挤压态7A04合金SIMA法生成触变组织为例．研究变形程度对其半固态触变组织的影响。结果表明：在加热前的变形程度对显微组织的影响很大，随着变形程度的增加，晶粒尺寸减小，晶粒形状越趋于球形；当变形程度超过0．3时，晶粒尺寸及其球形化速度逐渐减慢并趋于稳定值。此外，经过冷变形后，晶粒内及晶粒间的偏析减小，晶界易被低熔点液相浸润．更易获得均匀的、近球形的触变组织。     

5A90Al-Li合金超塑性变形过程中的显微组织及微观织构演变

通过采用电子背散射衍射技术研究具有扁平状组织的5A90 Al-Li合金板材在变形条件475℃、8×10^-4S^-1时的显微组织演变。结果表明,在进行超塑性变形前,其显微组织表现为扁平状组织,具有大量的小角度晶界,且初始板材具有明显的黄铜织构{110}（112）。在变形过程中发生了晶粒的长大、晶粒形貌的改变、晶粒取向差的增大以及织构的弱化,而且大角度晶界的含量在流动应力到达最大值后开始逐渐增加。同时,对不同阶段的相关变形机制进行了讨论。超塑性变形初始阶段的主要变形机制为位错运动,随着变形的进行而开始发生动态再结晶,晶粒旋转作为晶界滑移的主要协调机制。在超塑性拉伸的最后大应变阶段,晶界滑移是主要的变形机制。     

Effects of isothermal heat treatment on microstructural evolution of semisolid Al-4Cu-Mg alloy

The authors investigated the effects of the isothermal heat-treatment conditions on the microstructural evolution and composition distribution of semisolid Al-4Cu-Mg alloy during isothermal heat treatment. The experimental results show that the microstructural evolution and composition distribution of semisolid Al-4Cu-Mg alloy are controlled by atom diffusion during the isothermal heat treatment process. Grain growth and spheroidization were promoted with the increase of the isothermal temperature and/or the holding time. Moreover, the higher the isothermal temperature, or the longer the holding time, the more segregation constituent elements occurred to the grain boundaries. The low melting structure at grain boundary is greatly affected by Cu. The microstructural evolution in the isothermal heat-treatment process is as follows: recovery, recrystallization, fragmentation, spheroidization, and coarsening. Such fragmentation, spheroidization, and grain growth of coalescence and Ostwald ripening are involved as main mechanisms in the isothermal heat-treatment process.     

Deformation induced phase rearrangement in near eutectic tin–lead alloy

Deformation induced microstructural changes in the near eutectic tin (Sn)–lead (Pb) alloy are investigated. This study is motivated by the thermomechanical reliability of solder materials used in microelectronic packages, with the primary objective of gaining fundamental understandings of pure mechanical effects without the influence of diffusion related phenomena. Bulk specimens, having an initial microstructure of equiaxed Pb-rich particles within the Sn-rich matrix, are subject to relatively fast deformations of tension, compression and bending. Microhardness indentation is employed to characterize the sliding behavior along grain boundaries and interphase boundaries. It is observed that phase rearrangement induced by boundary sliding commences when the overall strain is still relatively small, giving rise to the gradual development of aligned regions free of the Pb-rich phase. These Pb-free zones, or equivalently Sn grain clusters, are aligned in the direction of macroscopic normal stresses. A micromechanical model, supported by further experimental evidences, is proposed to explain the observed microstructural changes. This study also illustrates the possibility of mechanically induced phase coarsening in Sn–Pb solder alloys.     

Al-4Cu-Mg合金半固态重熔时的组织演变

文章研究了Al-4Cu-Mg合金半固态重熔过程中加热温度和保温时间对微观组织形貌和α晶粒尺寸的影响,并对组织演化机制进行了探讨。实验结果表明,当加热温度较低或保温时间较短时,晶粒尺寸小且均匀性差。由于液相分数少,α晶粒之间粘连严重。随着加热温度的升高或保温时间的延长,α晶粒发生了长大和圆整化。对于Al-4Cu-Mg合金来说,合适的半固态重熔参数为:加热温度为540℃~580℃;保温时间小于10min。在半固态重熔过程中,α晶粒的合并长大和Ostwald长大是其微观组织演化的主要机制,两种晶粒长大机制在重熔过程中所起的作用受液相体积分数的影响。     

均匀化处理对含钪Al-Zn-Mg-Zr合金组织的影响

采用金相分析、扫描电镜、能谱分析、DSC等手段研究含钪Al-Zn-Mg-Zr合金均匀化态显微组织的演变。结果表明：在合金铸态组织中存在大量的枝晶偏析,在晶界处存在很多低熔点共晶相,主要元素在枝晶内部区域呈周期性变化;合金中元素Zn、Mg和Cu在晶内及晶界分布不均匀;在均匀化过程中,随着均匀化温度的升高或时间的延长,残留相逐渐溶入基体,元素分布逐渐均匀。合金的过烧温度为476.7°C。当均匀化温度升高到480°C时,合金中开始出现复熔球和三角晶界。综合考虑：合金的最佳均匀化制度为470°C,24 h。     

Microstructural evolution of equal channel angular pressed AZ91D magnesium alloy during semi-solid isothermal heat treatment

The microstructural evolution of AZ91D magnesium alloy processed by equal channel angular pressing during isothermal heat treatment at 570℃ was investigated. The results indicated that the equal channel angular pressing followed by semi-solid isothermal heat treatment was an effective method to prepare semisolid nondendritic slurry of AZ91D magnesium alloy. During this process, its microstructure change underwent four stages, the initial coarsening stage, the structure separation stage, the spheroidization stage and the final coarsening stage. The microstructural spheroidization effect was the best after being heated for 15 min for the alloy pressed for four passes, and the grain size was the smallest. With the further increase of heating time, the grain size and shape factor increased. When the heating time was kept constant, the grain size and shape factor decreased with the increase of pressing passes.     

120°模具室温ECAP制备工业纯钛的热压缩变形行为

在Gleeble-1500热模拟机上对室温120°模具等径弯曲通道变形(ECAP)制备的平均晶粒尺寸为200nm的工业纯钛(CP-Ti)进行等温变速压缩实验,研究超细晶(UFG)工业纯钛在变形温度为298～673K和应变速率为10-3～100s-1条件下的流变行为。利用透射电子显微镜分析超细晶工业纯钛在不同变形条件下的组织演化规律。结果表明:流变应力在变形初期随应变的增加而增大,出现峰值后逐渐趋于平稳;峰值应力随温度的升高而减小,随应变速率的增大而增大;随变形温度的升高和应变速率的降低,应变速率敏感性指数m增加,晶粒粗化,亚晶尺寸增大,再结晶晶粒数量逐渐增加;超细晶工业纯钛热压缩变形的主要软化机制随变形温度的升高和应变速率的降低由动态回复逐步转变为动态再结晶。     

变形温度对形变强化相变完成时临界应变量的影响

利用“形变强化相变”机制研究了低碳钢过冷奥氏体在740℃和780℃,10s-1变形时的变形温度对相变完成时临界应变量εc的影响。结果表明,变形温度对εc和组织演变的影响很大。在740℃和780℃变形时,εc分别为0.96和1.39,变形温度降低明显促进了相变。变形温度对εc的影响在组织演变上主要表现为铁素体形核地点的不同。740℃变形时,铁素体由奥氏体晶界形核过渡到以形变带形核为主,形核速率极高;780℃变形时,铁素体由奥氏体晶界形核过渡到在铁素体/奥氏体相界面前沿高畸变区快速形核。     

Coarsening rate of microstructure in semi-solid aluminium alloys

The rate of microstructural coarsening of recrystallisation and partial melting (RAP) and cooling slope (CS) processed materials in the semi-solid state is compared with rates found in the literature. The rate of coarsening depended on the liquid fraction but RAP route 2014 alloy with 37% liquid coarsened slightly more slowly than the CS route 2014 alloy with a lower liquid fraction of 17%, contrary to expectations. For the CS route, an increase in liquid fraction resulted in faster coarsening. A modified 2014 alloy with Fe, Mn and Zn stripped out of the composition gave a relatively high coarsening rate. The coarsening rate was also relatively high for CS 201 alloy in comparison with either RAP 2014 or CS 2014. Low coarsening rates are thought to be associated with the presence of particles which inhibit the migration of liquid film grain boundaries. This could be the result of pinning or of the liquid film impeding diffusion at the boundary.