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Journal of rare earths 2012年第8期30卷 835-841页

作者： Bahcine BAKIZ Lamia BOURJA Abdeljalil BENLHACHEMI Frédéric GUINNETON Madjid ARAB Jean-Raymond GAVARRI Institute Materials Microelectronics & Nanosciences of Provence UMR CNRS 6242 University SOUTH Toulon-Var Laboratory Materials & Environment Faculty of Sciences University Ibn Zohr

A comparative study of reactivity between air-CH4 or air-CO gas flows and CeO2, La2O3 and Lu2O3 rare earth oxides was per- formed using Fourier transform infrared spectroscopy analyses of CO2 gas resulted from the conversion of CH4 or CO gases. Polyerystalline samples of CeO2, La2O3 and Lu2O3 were first prepared by specific precipitation methods followed by low temperature calcination process. In the case of Lu2O3 oxide, a new specific route was proposed. Crystallite dimensions were determined by X-ray diffraction and transmission electron microscopy analyses. Morphologies were characterized using scanning electron microscopy. Specific surface areas were determined from Bnmauer-Emmett-Teller （BET） technique. Using infrared spectroscopy analyses, the conversion rates of CH4 or CO into CO2 were de- termined from the evolutions of CO2 vibrational band intensities, as a function of time and temperature. It was dearly established that, despite its low specific surface, the Lu2O3 oxide presented the highest capacity of conversion of CH4 or CO into CO2.

关键词： lutetium oxide rare earth oxides elaboration gas solid interactions infrared spectroscopy

In situ synthesis of polycrystalline cubic boron nitride in cBN-Al-Ti system with different Gd_(2)O_(3) additions

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rare Metals 2021年第5期40卷 1267-1274页

作者： Sheng-Lin Zhong Zhi-Kai Li Chao Chen Chuan Chen Peng Wang Yi Wu College of Materials Science and Engineering Guilin University of TechnologyGuilin 541004China

Polycrystalline cubic boron nitride was sintered under high temperature(1400℃)and high pressure(5.5 GPa)using an in situ synthesis *** composition,microstructure,relative density and mechanical properties of the polycrystalline cubic boron nitride(PcBN)with different contents of Gd_(2)O_(3) were studied by means of X-ray diffraction(XRD),scanning electron microscopy(SEM)and energy-dispersive spectroscopy(EDS).The results show that the phases of TiB_(2),TiN,AIN,AlTi_(2)N and GdB_(6) are formed through in situ synthesis of cBN-Al-Ti-Gd_(2)O_(3) *** the Gd_(2)O_(3) content increasing,the relative density increases and mechanical properties of PcBN begin to increase and then *** amount of Gd_(2)O_(3) can advance the formation of TiB_(2) and improve the aspect ratio of TiB_(2).When Gd_(2)O_(3) content is 1.0 wt%,the PcBN exhibits optimal comprehensive mechanical properties,with a microhardness of 33.35 GPa and a flexural strength of 972.37 MPa.

关键词： Polycrystalline cubic boron nitride(PcBN) TiB_(2) Rod crystal rare earth oxides Mechanical properties

Effect of rare earth La_2O_3 on the microstructure and mechanical properties of TiC/W composites

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rare Metals 2008年第6期27卷 632-636页

作者： CHEN Yong WU Yucheng YU Fuwen CHEN Junling School of Materials Science and Engineering Hefei University of Technology Hefei 230009 China Institute of Plasma Physics Chinese Academy ofSeienees Hefei 230031 China

In this study, La2O3 was investigated as an additive to TiC/W composites. The composites were prepared by vacuum hot pressing, and the microstructure and mechanical properties of the composites were investigated. Experimental results show that the grain size of the TiC/W composites is reduced by TiC particles. When 0.5 wt.% La2O3 is added to the composites, the grain size is reduced further. According to TEM analysis, La2O3 can alleviate the aggregation of TiC particles. With La2O3 addition, the relative density of the TiC/W composites can be improved from 95.1% to 96.5%. The hardness and elastic modulus of the TiC/W ＋ 0.5 wt.% La2O3 composite are little improved, but the flexural strength and the fracture toughness increase to 796 MPa and 10.07 MPa·m^1/2 respectively, which are higher than those of the TiC/W composites.

关键词： TiC/W composites rare earth oxides microstructure mechanical properties

Influence of Al_2O_3/CeZrAl composition on the catalytic behavior of Pd/Rh catalyst

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Journal of rare earths 2010年第1期28卷 59-63页

作者：贺小昆孙加林桓源峰胡劲杨冬霞 Material and Metallurgy Engineering College Kunming Science & Technology University Kunming Sino-Platinum Metals Catalyst Co. Ltd.

Al2O3 and Ce-Zr mixed oxides are important components of the automobile three-way *** contents modifying A12O3(GAL) was physically introduced into Ce-Zr-Al mixed oxides(CZA) to form series of GAL/CZA *** Pd/Rh catalyst samples were prepared by different GAL/CZA support loading Pd/Rh,then aged at 950 oC for 6 *** catalytic behavior of different Pd/Rh catalyst samples was *** area,oxygen storage capacity(OSC) and H2 adsorption capacity(TPR) of fresh and aged samples were...

关键词： alumina rare earth oxides Pd/Rh catalyst automobile exhaust purification

稀土氧化物对TiB2陶瓷致密化程度的影响（英文）

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哈尔滨工业大学学报 1993年第5期 133-136页

作者：吴文芳葛启录吴危杭王盛宏焦炜光哈尔滨工业大学应用化学系

1 IntroductionThe merits of TiB;ceramics:high hardness,high melting point,chemical stability athigh temperature,wear-resisting,corrosion-resisting and good heat-conduction lead itto have various latent usages in chemical engineering, electro-engineering and otherhigh *** its applications are seriously limited due to the fact that it is easy togrow into coarse grains during sintering and difficult to obtain high dense TiB;*** is,therefore,necessary to find some effective additives as the second *** work has approached the densification process by adding rare earth oxides Y;O;,La;O;and CeO;.

关键词： TiB2 ceramics rare earth oxides densification

Study on electrochemical preparation of Al-Li-Y alloys from Y_2O_3 in LiCl-KCl-AlCl_3 molten salts

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Journal of rare earths 2011年第4期29卷 378-382页

作者：黎亚明王凤丽张密林韩伟田阳 Key Laboratory of Superlight Materials and Surface Technology Ministry of Education College of Materials Science and Chemical Engineering Harbin Engineering University

The electrochemical preparaton of Al-Li-Y alloys from LiCl-KCl-AlCl3-Y2O3 system was studied. The chlorination of Y2O3 by AlCl3 led to the formation of Y （III） ions in the molten salts. Cyclic voltammogram （CV） showed that the underpotential deposition （UPD） of yttrium on pre-deposited aluminum caused the formation of Al-Y alloy. Al-Li-Y alloys with different yttrium contents were obtained by galvanostatic electrolysis and analysed by SEM-EDS and ICP. The ICP results showed that the lithium and yttrium contents in Al-Li-Y alloys depended on the addition of AlCl3 into the melts.

关键词： Al-Li-Y alloys molten salts electrochemical deposition rare earth oxides

Structural and optical properties of Er_2O_3 films

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Journal of rare earths 2010年第5期28卷 752-755页

作者：朱燕艳方泽波刘永生 Department of Mathematics and Physics Shanghai University of Electric Power Surface Physics Laboratory (National Key Laboratory) Fudan University

Stoichiometric and amorphous Er2O3 films were deposited on Si(001) substrates by radio frequency magnetron technique. Spectroscopic ellipsometry measurement showed that the refractive index of the Er2O3 film in wavelength region of 400–1000 nm was between 1.6–1.7. The reflectivity of the Er2O3 films decreased greatly with respect to that from the uncoated Si substrates. The absorption coefficient of the Er2O3 film indicated that it had an energy gap larger than 4.5 eV. The obtained characteristics indicated...

关键词： optical constants rare earth oxides solar cells

Study on vacuum ultraviolet spectra of amorphous Er_2O_3 films on Si(001) substrates

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Journal of rare earths 2011年第9期29卷 888-890页

作者：朱燕艳方泽波徐闰陈静曹海静李慧玉 Department of Mathematics and Physics Shanghai University of Electric Power Department of Physics Shaoxing University School of Materials Science and Engineering Shanghai University

Amorphous Er2O3 films have been fabricated on p-type Si（001） substrates using radio frequency magnetron sputtering technique. Vacuum ultraviolet spectra were employed to investigate the samples. An optical gap of 6.17 eV for Er2O3 films was obtained from the ab-sorption coefficient spectra. A possible reason was put forward to explain the inconsistent results about the band gap of Er2O3 in literatures. Emission spectra exhibited a strong emission band at 494 nm with the incident ultraviolet light of 249 nm. The observed high density of emission bands of Er2O3 films in the visible wavelength indicated that Er2O3 films could be used in Si solar cells for increasing conversion efficiency.

关键词： optical properties rare earth oxides solar cells

Optical constants of Er_2O_3-Al_2O_3 films studied by spectroscopic ellipsometry

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Journal of rare earths 2011年第10期29卷 958-960页

作者：朱燕艳方泽波徐闰 Department of Mathematics and Physics Shanghai University of Electric Power Department of Physics Shaoxing University School of Materials Science and Engineering Shanghai University

Er2O3-Al2O3 fulm was deposited on the Si（001） substrate by radio frequency magnetron technique at room temperature. The sample was annealed at 450, 600 and 750℃ for 30 rain in 02 ambience, respectively. The optical constants were studied by spectroscopic ellipsometry for both the as-deposited and the annealed samples. The proper values of refractive index indicated that it could be a useful material for solar cells.

关键词： optical properties rare earth oxides solar cells

Effect of cerium on abrasive wear behaviour of hardfacing alloy

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Journal of rare earths 2012年第1期30卷 69-73页

作者：行舒乐余圣甫邓宇戴明辉余露 State Key Laboratory of Material Forming and Mould&Die Designing Huazhong University of Science and TechnologyWuhan 430074China

Hardfacing alloys with different amounts of ceria were prepared by self-shielded flux cored arc *** abrasion tests were carried out using the dry sand-rubber wheel machine according to JB/T 7705-1995 *** hardness of hardfacing deposits was meas-ured by means of HR-150AL Rockwell hardness test and the fracture toughness was measured by the indentation *** characterization and surface analysis were made using optical microscopy,scanning electron microscopy（SEM） and energy spectrum *** results showed that the wear resistance was determined by the size and distribution of the carbides,as well as by the matrix *** main wear mechanisms observed at the surfaces included micro-cutting and micro-ploughing of the *** addition of ceria improved the hardness and fracture toughness of hardfacing deposits,which would increase the resistance to plastic deformation and scratch,thus the wear resistance of hardfacing alloys was improved.

关键词： abrasive wear carbides rare earth oxides