材料期刊网

BEHAVIOUR OF α-NITROSO-β-NAPHTHOL IN HEMATITE FLOTATION

WANG Wenmei Baotou Research Institute of Rare Earth , Ministry of Metallurgy Industry , Baotou , ChinaYU Yongfu CHEN Quanyuan Changsha Institute of Mining and Metallurgy , Ministry of Metallurgy Industry , Changsha , China engineer , Baotou Research Institute of Rare Earth , Ministry of Metallurgical Industry , Baotou 014010 , China

金属学报(英文版)

Based on theoretical calculation of electronegativity of groups of flotation reagent and method of infrared adsorption spectroscopy,the collection and adsorption of α-nitroso-β- naphthol in hematite flotation have been studied.The chemical adsorption seems to be predominant owing to formation of pentacyclic nitrosyl chelate compound by atoms of nitrosyl bond in α-nitroso-β-naphthol together with Fe(Ⅲ)on hematite surface.Mean- while,the nonuniform multilayer physical adsorption is also occurred.

关键词: α-nitroso-β-naphthol , null , null , null , null

Recovery of iron from Baotou rare earth tailings by magnetizing roast

稀有金属（英文版） doi:10.1007/s12598-013-0158-2

关键词:

Metastable phases in rare-earth permanent-magnet materials

Journal of Physics D-Applied Physics

A comprehensive review is given of recent advances in the study of metastable phases in rare-earth permanent magnets. The relations between the structures of the metastable and equilibrium phases and the transformations from the former to the latter are discussed. The formation of the phases is found to depend on the difference between the symmetries of the metastable and equilibrium phases. The magnetic properties of the metastable-phase rare-earth permanent magnets synthesized by various processes, such as mechanical alloying, mechanical milling, rapid quenching, hydrogenation, disproportionation, desorption and recombination, solid-state reaction, solid-gas reaction, self-flux and sputtering, are compared. The main conclusion of this article is that searching for new metastable phases with high magnetic performance will be one of the most active directions in the research on rare-earth permanent magnets.

关键词: fe-c alloys;disproportionation-desorption-recombination;solidified;sm-fe;r = nd;high-coercivity;magnetocrystalline anisotropy;intermetallic compounds;remanence enhancement;crystal-structure;high-performance

EFFECT OF RARE EARTH ON VANADIZATION PROCESS IN BORAX BATH

X.K. Tao , X.Cong , R.S. Peng , J.Liu and Z.Y. Liu Tianjin Institute of Technology , Tianjin 300191 , China

金属学报(英文版)

This paper investigates the effect of rare earth elements on the kinetic process, microstructure and mechanical properties of vanadization in borax bath. The results show that addition of rare earth elements to vanadizing agent has obvious catalytic effect on the rate of vanadization, which has been enchanced by 30%. The wear and corrosion resistance of vanadium carbide layer were prompted by the addition of rare earth to the agent. Through increasing vanadium potential of the agent, activating the surface of workpieces and decreasing the activation energy of diffusion of carbon, rare earth elements accelerate the rate of vanadization process.

关键词: rare earth elements , null , null

SYNTHESIS AND IDENTIFICATION OF CONDUCTING POLYANILINE DOPED WITH RARE EARTH CHLORIDE

C.M. Yang , Q.R. Zhang and Z. Fang(Department of Chemistry , Central South University of TecHnology , Changsha 410083 , China)

金属学报(英文版)

Polyaniline doped with rare earth chloride was synthcsized in organic solvent and identified by clemental analysis and ithered spectroscopy. The experimental results show that there exist both doping and complexation at the same time in the resulting product. When pH<4, prototnic acid doping is predominating, whereas rare earth ion complexation is predominating when pH>1. Moreover, polyanitine doped wih rare earth chloride exhibits better thermal stability than that doped with hydrochloric acid.

关键词: dope , null , null , null

Action of New Rare Earth Additions in Cemented Carbide

Chenguang LIN General Research Institute for Non-ferrous Metals , Beijing , 100088 , China

材料科学技术（英文）

The existence form and distribution of new rare earth additions in WC-Co,WC-TiC-Co.Cemented carbide and its actions of purification,modificaiton,solid solution strengthening and restraining phase transformation have been investigated.The results have been used to elucidate property im- provement of the alloys.

关键词: cemented carbide , null , null

Enhanced electron correlation in rare-earth doped Ca(3)Co(4)O(9)

Applied Physics Letters

Thermoelectric and thermodynamic properties of a series of Ca-site rare-earth R(3+) doped Ca(3)Co(4)O(9) were investigated. For a fixed doping level, with the reduction in R(3+) radius, thermopower is found to gradually increase despite the carrier concentration remains unchanged. The scaling behavior between thermopower and electron specific heat coefficient reveals that the additional increase in thermopower originates from enhanced electron correlation which may be attributed to doping-induced chemical pressure. (C) 2010 American Institute of Physics. [doi:10.1063/1.3479923]

关键词: calcium compounds;carrier density;doping profiles;electron;correlations;rare earth metals;specific heat;thermoelectric power;misfit-layered cobaltite;thermoelectric properties;system;substitution;transition;transport;ceramics

Highly transparent cathodes comprised of rare earth and Au stacked layers for top-emission organic light emitting diodes

Journal of Applied Physics

We report the transparent cathodes comprised of a low work function rare earth element (RE) and a Au capping layer for top-emission organic light emitting diodes (TOLEDs). The Sm/Au, Yb/Au, Gd/Au, and Dy/Au cathodes possess a transmittance up to similar to 60% when the RE/Au thickness is 5/10 nm. The light extraction efficiencies for the TOLEDs with a silicon anode and a RE/Au cathode are computed to be 9%-13%, markedly higher than that for a similar device but with an Al/Au cathode. The surface plasmon polaritons at the Yb(or Sm)/Au cathode are found to be much weaker than those at the Al/Au cathode. (c) 2006 American Institute of Physics.

关键词: interfacial chemistry;silicon anode;thin-films;devices;efficiency;microcavities;extraction;electrode;alq(3)

Densification and Sintering Kinetics of Rare Earth (α′+ β′)-Sialon Composites

Hao WANG , T.S.YEN , Hanrui ZHUANG and Weiying SUN (State Key Lab. on High Performance Ceramics and Superfine Microstructure , Shanghai Institute of Ceramics , Chinese Academy of Sciences , Shanghai , 200050 , China)

材料科学技术（英文）

The sintering processes of Re-(α' + β')-sialon composites (Re=Sm, Dy, Yb) have been investigated by using a specially designed high temperature dilatometer. The initial densification of various samples starts at about 1200℃, and the maximum shrinkage rate of these sialon composites occurs at about 1500℃. The light rare earth sialon has a noticeably tower densification temperature and a higher final shrinkage. The sirtering kinetics of Re-(α' +β')-sialonare much more complex. The Kingery's liquid phase sintering model appears to be applicable,but the mechanism of mass transport in stage two appears to be changeable. The controlling factor shiffs from solution-precipitation to diffusion when densification process proceeds from the earlier part to the later part of this stage.

关键词:

Effect of rare earth metals on solidification behaviour in nickel based superalloy

Materials Science and Technology

The effect of rare earth metals (REMs) on the microstructure and segregation during solidification in a highly alloyed Ni based superalloy was investigated. Rare earth metals considerably decrease the amounts of coarse columnar grains and increase the amounts of equiaxed grains. They are segregated to the interdendritic regions mainly as the precipitate of Ni5Ce. Both the dimension and distribution of gamma' particles and MC carbide are modified by REM. Eutectic (gamma+gamma'), Laves phase, delta phase and sigma phase are precipitated in the interdendritic regions because of the serious segregation of niobium and titanium aggravated by REM. The differential thermal analysis indicates that the precipitation temperature of phases and the solidification sequence of the superalloy can be changed due to the additions of REM.

关键词: Rare earth metals;Segregation;Solidification;Nickel based superalloy;microstructure;segregation;steel;alloy