材料期刊网

PHASE DIAGRAMS OF KF-LiCI-BaCl_2 AND LiF-LiCI-BaCl_2 SYSTEMS

YAN Licheng YANG Jinxiu ZHU Lei , XU Jingyan Shanghai University of Science andTechnology , Shanghai , ChinaFAN Jinxia Suzhou Teachers′ School , Suzhou , China YAN Licheng , Associate Professor , Dept.of Chemistry , Shanghai University of Science and Technology , Shanghai 201800 , China

金属学报(英文版)

The phase diagrams of molten salt systems KF-LiCI-BaCl_2 and LiCI-LiF-BaCl_2 have been determined by visual polythermal method.The relationship between the change of cation radius of monovalent fluoride and the areas of primary crystal region in the phase diagrams is discussed.

关键词: phase diagram , null , null , null , null

COMPUTERIZED SIMULATION OF MOLTEN SALT SOLUTION OF Li,KF,Cl SYSTEM BY MOLECULAR DYNAMIC METHOD

SHAO Jun Shanghai University of Science and Technology , Shanghai , ChinaXU Hua CHEN Nianyi Shanghai Institute of Metallurgy , Academia Sinica , Shanghai , China SHAO Jun Associate Professor , Dept.of Chemistry , Shanghai University of Science and Technology , Shanghai 201800 , China

金属学报(英文版)

The structure and properties of molten salt solution o J Li,KF,Cl system have been investigedby computerized simulation of molecular dynamic method.The partial RDF,the partial molarenergy of mixing and the diffusion coeffients of Li~+,K~+,F~- and Cl~- have been calculated.The results are in agreement with the experimental values.The regularities of the distributionof ions and mieroscopic holes are discussed based on the results of computerized simulation.

关键词: alkali halide , null , null , null

ANODIC PROCESSES FOR ELECTROWINNING OF Sb FROM JAMESONITE CONCENTRATE

ZHAO Ruirong JIANG Hanying QIN Yihong ZENG Zhenou YANG Jiyue Central South University of Technology , Changsha , China ZHAO Ruirong , Associate Professor , Dept.of Chemistry , Central South University of Technology , Changsha 410083 , China

金属学报(英文版)

The anode reaction and current density of the electrowinning of Sb from jamesonite concen- trate have been investigate.High anodic current density seems to be the major reason for high energy consumption,air pollution by alkaline mists in workshop as well as poor quality of deposition.A series of steps,such as absorption,phase formation,ageing of passivated films etc.,were found to be involved during the anodic passivating process of Fe in NaOH solution. A new anodic material Fe/Ni/Co_3O_4 was developed so as to save the d.c.electric energy over 160 kWh/t of Sb.

关键词: Sb , null , null , null

A NEW MOLYBDENUM OXIDE PHASE

FANG Zheng ZHANG Pingmin CHEN Xinmin Central-South University of Technology , Changsha , China FANG Zheng , Associate Professor , Dept.of Chemistry , Central South University of Technology , Changsha 410083 , China

金属学报(英文版)

A new molybdenum oxide phase which exists in bomb combustion products of Mo was found. It has been determined that this phase is a transformed MoO_3 of triclinic system.One set of its lattice parameters was also determined from the X-ray diffraction data as α=0.4049± 0.0001 nm,b=0.5079±0.0003 nm,c=1.4339±0.0009 nm,α=115.16±0.08°,β=90.69± 0.14°,γ=105.58±0.05° and unit cell volume=0.2544 nm~3.

关键词: Mo oxide , null , null

BEHAVIORS OF Sb,Sn AND As IN LEACHING AND ELECTROWINNING FROM JAMESONITE CONCENTRATE

ZHAO Ruirong JIANG Hanying ZENG Zhen'ou QIN Yihong XU Shun Central South University of Technology , Changsha , China ZHAO Ruirong Associate Professor , Dept.of Chemistry , Central South University of Technology , Changsha 410083 , China

金属学报(英文版)

The separating efficiency of Sb from As and Sn in jamesonite concentrate could be improved by changing the composition of leaching solution and other conditions.The related kinetic parameters of electrode reaction were evaluated under discussion on the form of complex ion AsS_3~(3-)in extract and the reduction at amalgam electrode.It was also discussed about the ef- fect of eoncentration of Na_2S and SbS_3~(3-)in solution on the current efficiency of SnS_4~(4-) reduction.

关键词: Sb , null , null , null , null

INTERACTION BETWEEN Cu AND LIQUID Sn—Also on Physical Meaning of Wetting Curve

ZHANG Qiyun HAN Wanshu LIU Junkang Peking University , Beijing , China ZHANG Qiyun Professor , Dept.of Chemistry , Peking University , Beijing 100871 , China

金属学报(英文版)

The interaction between Cu and liquid Sn was studied by microstructure observation.The curve of the dipping time with related to dissolving and diffusion of Cu in liquid Sn is given. The Cu dissolves rapidly in liquid Sn at the beginning,then an intermetallic compound Cu_6Sn_5 forms,and the dissolving follows to slow down.At temperature up to 350℃,the hard feather-like Cu_6Sn_5 is sharply growing up and speads through the dipped Sn laver.The way to inhibit the growth of the intermetallic compound Cu_6Sn_5 was also approached.Thus,on the above mentioned basis,the physical meaning of the wetting curve traced by the meniscograph wettability tester has been derived as film detaching,Cu dissolying and Cu_6Sn_5 growing.

关键词: Cu , null , null , null , null

用DEPT135测定Resol的组成及微细结构参数

杨金瑞 , 余尚先 , 顾江楠

高分子材料科学与工程

通过对resol(羟甲基酚化合物和低分子量羟甲基酚树脂)DEPT135图谱的分析讨论,得到一系列计算resol微细结构参数的经验公式.根据DEPT135图谱可判断是否发生缩聚反应,根据经验公式可计算酚单体各个活性点参与反应百分率或酚羟基导入率、不同类型缩聚所占百分率及低分子量羟甲基酚树脂的平均核体数.

关键词: 羟甲基酚化合物 , 羟甲基酚树脂 , DEPT135 , 结构参数

Metal-Free Heterogeneous Catalysis for Sustainable Chemistry

Chemsuschem

The current established catalytic processes used in chemical industries use metals, in many cases precious metals, or metal oxides as catalysts. These are often energy-consuming and not highly selective, wasting resources and producing greenhouse gases. Metal-free heterogeneous catalysis using carbon or carbon nitride is an interesting alternative to some current industrialized chemical processes. Carbon and carbon nitride combine environmental acceptability with inexhaustible resources and allow a favorable management of energy with good thermal conductivity Owing to lower reaction temperatures and increased selectivity, these catalysts could be candidates for green chemistry with low emission and an efficient use of the chemical feedstock This Review highlights some recent promising activities and developments in heterogeneous catalysis using only carbon and carbon nitride as catalysts The state-of-the-art and future challenges of metal-free heterogeneous catalysis are also discussed.

关键词: carbon;catalyst;heterogeneous catalysis;selectivity;sustainable;chemistry;graphitic carbon nitride;modified activated carbon;nanofiber/graphite-felt composite;ordered mesoporous carbons;oxygen;reduction reaction;nitrogen-doped graphite;fuel cell cathode;onion-like carbon;oxidative dehydrogenation;hydrogen-production

SERS and Quantum Chemistry Studies of Adsorption of Thiourea and Ethylthiourea on Silver Electrode

Acta Physico-Chimica Sinica

Adsorption of thiourea (TU) and ethylthiourea( ETU) on roughened silver electrode was investigated using in situ surf. enhanced Raman spectroscopy(SERS) Using quantum chemistry and HSAB theories, the influences of electrode potential and the different substituent groups on SERS were disc i. TU is chemisorbed perpendicularly by Ag-S bond on silver at E = -0.3 V and adsorption of TU turns into a parallel orientation at E = -0.9 V. ETU is always chemisorbed at an angle from Ag. The adsorption of ETU is through and C=C and C=O groups at E = -0.3 V, and mainly through C=C at E = -0.9V.

关键词: Surface enhanced Raman spectroscopy;Adsorption;Quantum chemistry;Thiourea;Inhibitor

LOCAL CHEMISTRY AND THE COHESIVE STRENGTH OF GRAIN BOUNDARIES IN Ni_3Al

Shanthi Subramanian , David Muller , John Silcox and Stephen L.Sass (Department of Materials Science and Engineering and Department of Applied and Engineering Physics , Cornell University , Ithaca. NY 14853)

金属学报(英文版)

Local chemistry plays an important role in determining the cohesive strength of grain boundaries in Ni3Al. Doping with B increases the room temperature ductility and changes the fracture mode from intergranular to transgranular, while doping with Zr increases the ductility but leaves the fracture mode predominantly intergranular.Electron Energy Loss Spectroscopy (EELS) and Energy Dispersive X-ray Spectroscopy (EDS) were used to probe the changes in local bonding (and hence the cohesive strength) produced by changes in local chemistry at large angle boundaries in Ni3Al.In addition , small angle tilt boundaries were studied to correlate structure with Nienrichment at the interface. B segregation to Ni-rich grain boundaries was shown to make the bonding similar to that of the bulk, thereby increasing their fracture resistance. Ni-enrichment does not occur in the presence of Zr segregation to grain boundaries. Ni-enrichment to antiphase boundaries (APB) in small angle tilt boundaries lowers the APB energy by reducing the number of high energy Al-Al interactions across the interface. Ni-enrichment to large angle boundaries is expected to produce a similar effect on energy.

关键词: : grain boundary chemistry , null , null , null