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Laser cladding in-situ carbide particle reinforced Fe-based composite coatings with rare earth oxide addition 被引量:21
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作者 吴朝锋 马明星 +3 位作者 刘文今 钟敏霖 张红军 张伟明 《Journal of Rare Earths》 SCIE EI CAS CSCD 2009年第6期997-1002,共6页
Particulate reinforced metal matrix composite(PR-MMC) has excellent properties such as good wear resistance,corrosion resistance and high temperature properties.Laser cladding is usually used to form PR-MMC on metal s... Particulate reinforced metal matrix composite(PR-MMC) has excellent properties such as good wear resistance,corrosion resistance and high temperature properties.Laser cladding is usually used to form PR-MMC on metal surface with various volume fractions of ceramic particles.Recent literatures showed that laser melting of powder mixture containing carbon and carbide-forming elements,was favorable for the formation of in-situ synthesized carbide particles.In this paper,rare earth oxide(RE2O3) was added into t... 展开更多
关键词 laser cladding particle reinforced rare earth oxide nucleation rare earth carbide
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Rare Earth Effects on Adhesion of Cr_2O_3 Oxide Scale Formed on Surface of Co-40Cr Alloy 被引量:13
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作者 靳惠明 张林楠 +1 位作者 李美栓 李铁藩 《Journal of Rare Earths》 SCIE EI CAS CSCD 2001年第1期34-39,共6页
Isothermal and cyclic oxidation behaviors of Co 40Cr alloy at 1000 ℃ in air were studied. Scanning electron microscopy (SEM) was used to examine the oxide scale formed on the surface of the alloy. By comparing the o... Isothermal and cyclic oxidation behaviors of Co 40Cr alloy at 1000 ℃ in air were studied. Scanning electron microscopy (SEM) was used to examine the oxide scale formed on the surface of the alloy. By comparing the oxidation behaviors of Co 40Cr alloy and its 3×10 16 and 3×10 17 Y +/cm 2 implanted specimens, it was found that the resistant to oxidation property of Co 40Cr was greatly improved due to the implantation of yttrium. Acoustic emission was used to study the distribution of defects at the interface between the scale and alloy. Raman spectrum was also used to study the stress status in chromic scale formed on the surface of Co 40Cr with and without yttrium. The main reason for the improvement of resistant to oxidation property of Y doped Co 40Cr probably is that yttrium can segregate to Cr 2O 3 grain boundaries and change the scale′s growing mechanism and mechanical property. Most importantly, Y implantation decreases the size and number of interfacial defects and the residual stress in the scale, and remarkably enhances the adhesion of chromia scale with Co 40Cr substrate. 展开更多
关键词 rare earths ADHESION oxidATION acoustic emission Raman spectrum
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Preparation of Rare Earth Hydroxide and Oxide Nanoparticles by Precipitation Method 被引量:8
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作者 Xiangting DONG Guangyan HONG 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2005年第4期555-558,共4页
A series of rare earth hydroxide and oxide nanoparticles have been prepared by precipitation method with alcohol as the dispersive and protective reagent. Transmission electron microscope (TEM) images indicate that ... A series of rare earth hydroxide and oxide nanoparticles have been prepared by precipitation method with alcohol as the dispersive and protective reagent. Transmission electron microscope (TEM) images indicate that the particles are spherical in shape and smaller than 100 nm in size. The crystallite sizes of cubic Ln2O3 have lanthanide shrinking effect, while average crystal lattice distortion rates possess lanthanide swelling effect. The diffraction peak intensity of heavy rare earth oxide nanometer powders is remarkably stronger than that of light rare earth oxide nanometer powders. The variation of diffraction intensity with atomic number presents an inverted W type, forming a double peak structure. Fourier transform infrared (FTIR) spectrums reveal that Ln2O3 nanopowders have higher surface activity than that of ordinary Ln2O3 powders. The UV-vis spectra show that Ln-O bond of these particles is slightly blue-shifted, and its absorption intensity decreases. 展开更多
关键词 rare earth rare earth hydroxide rare earth oxide NANOPARTICLE Precipitation method
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Effect of mixed rare earth oxides and CaCO_3 modification on the microstructure of an in-situ Mg_2Si/Al-Si composite 被引量:9
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作者 Liu, Zheng Lin, Jixing Jing, Qingxiu 《Rare Metals》 SCIE EI CAS CSCD 2009年第2期169-174,共6页
The effects of mixed rare earth oxides and CaCO3 on the microstructure of an in-situ Mg2Si/Al-Si hypereutectic alloy composite were investigated by optical microscope,scanning electron microscope,and energy dispersive... The effects of mixed rare earth oxides and CaCO3 on the microstructure of an in-situ Mg2Si/Al-Si hypereutectic alloy composite were investigated by optical microscope,scanning electron microscope,and energy dispersive spectrum analysis. The results showed that the morphol-ogy of the primary Mg2Si phase particles changed from irregular or crosses to polygonal shape,their sizes decreased from 75 μm to about 25 μm,and the compound of both the oxide and CaCO3 was better than either the single mixed rare earth o... 展开更多
关键词 hypereutectic alloys Al-Si alloys COMPOSITE rare earth oxides MODIFICATION
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Thermodynamics of Modifying Effect of Rare Earth Oxide on Inclusions in Hardfacing Metal of Medium-High Carbon Steel 被引量:7
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作者 赵研辉 李艳丽 +1 位作者 姚枚 杨庆祥 《Journal of Rare Earths》 SCIE EI CAS CSCD 2002年第4期291-294,共4页
The modifying effect of rare earth (RE) oxide on inclusions in hardfacing metals of medium-high carbon steel was investigated by means of thermodynamics. The thermodynamic analysis for inclusion formation shows that ... The modifying effect of rare earth (RE) oxide on inclusions in hardfacing metals of medium-high carbon steel was investigated by means of thermodynamics. The thermodynamic analysis for inclusion formation shows that RE oxide can be reduced to RE element by carbon, then the RE element can react with oxygen and sulfur to form the RE oxide, RE sulfide and RE oxide-sulfide in hardfacing molten pool. The deoxidization and the desulphurization can be carried out and the liquid metal can be purified. In addition, RE oxide can also react with sulfur to form RE oxide-sulfide directly. Therefore, the harmful effect of sulfur can be decreased. 展开更多
关键词 rare earths oxide INCLUSION hardfacing metal THERMODYNAMICS
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Phase Behavior and Crystal Structure of Perovskite-Type Rare Earth Complex Oxides 被引量:8
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作者 Migaku Kobayashi Ryoko Katsuraya +3 位作者 Tsubasa Nara Yusuke Tomita Hiromi Nakano Naoki Kamegashira 《Journal of Rare Earths》 SCIE EI CAS CSCD 2006年第6期668-672,共5页
Several compounds of rare earth complex oxides containing manganese and titanium were synthesized in Ar, and their crystal structures were analyzed by powder X-ray diffraction data and Rietveld method. Structures of A... Several compounds of rare earth complex oxides containing manganese and titanium were synthesized in Ar, and their crystal structures were analyzed by powder X-ray diffraction data and Rietveld method. Structures of A0.67Ln0.33 Mn0.33Ti0.6703(A = Ca or Sr and Ln = rare earth) were found to have orthorhombic symmetry with the space group Pnrna, and their interatomic distances and bond angles were obtained. This space group was also derived from electron microscopic study. Electrical conductivity of Cao.67Ln0.33Mn0.33Ti0.6703 for several rare earth elements showed a semiconducting property with the activation energy of 0.4 eV. Some of these compounds of the strontium system show the antiferromagnetic properties below 10 K. 展开更多
关键词 perovskite crystal structure X-ray diffraction alkaline earth rare earth manganese titanium oxide
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Preparation and Characterization of Microporous Nano-Tungsten Trioxide and Its Photocatalytic Activity after Doping Rare Earth 被引量:7
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作者 邹丽霞 钟秦 刘庆成 《Journal of Rare Earths》 SCIE EI CAS CSCD 2006年第1期60-66,共7页
Aqueous sols and gels of tungstic acid were prepared from Na2WO4 with protonated cation-exchange resin. Nano-tungsten oxide of a microporous lamella was synthesized by means of washing of WO3· 2H2O with distilled... Aqueous sols and gels of tungstic acid were prepared from Na2WO4 with protonated cation-exchange resin. Nano-tungsten oxide of a microporous lamella was synthesized by means of washing of WO3· 2H2O with distilled water under ultrasonic wave agitation and centrifuging repeatedly, and the specific surface area tended to increase gradually with washing and centrifuging. The sample of centrifuged 7 h has more than 2 times highs specific surface area and more high photocatalytic activity . The mechanisms are also discussed. 展开更多
关键词 tungstic acid gels washing and centrifuging MICROPOROUS specific surface area PHOTOCATALYTIC rare earth oxides
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Mechanism of Cracking Resistance of Hardfacing Specimens of Steel 5CrNiMo Improved by Rare Earth Oxide 被引量:6
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作者 杨庆祥 任学军 +3 位作者 刘利刚 李达 董海峰 廖波 《Journal of Rare Earths》 SCIE EI CAS CSCD 2006年第4期471-478,共8页
The cracking morphology of the hardfacing specimens taken from steel 5CrNiMo was observed. Meanwhile, the residual stress fields were measured and simulated. Based on experiment mentioned above, the improved structure... The cracking morphology of the hardfacing specimens taken from steel 5CrNiMo was observed. Meanwhile, the residual stress fields were measured and simulated. Based on experiment mentioned above, the improved structure and modified inclusion in hardfacing metal with rare earth (RE) oxide were analyzed. The results show that, the hardfacing crack is initiated from the coarse dendritic crystal grain boundary, inclusions and coarse austenite grain boundary in the HAZ and propagated by the residual stress existing in the center of the hardfacing metal and HAZ. The primary columnar grain structure can be refined by adding RE oxide in the coating of the electrode. The inclusion in the hardfacing metal can be modified as well. Meanwhile, if the martensite transformation temperature is decreased, the largest value of the residual tensile stress in the dangerous region can be reduced. 展开更多
关键词 green remanufacture hot forged die medium-high carbon steel hardfacing materials rare earth oxide
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Hydrogen production from coke oven gas over LiNi/γ-Al_2O_3 catalyst modified by rare earth metal oxide in a membrane reactor 被引量:6
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作者 Zhibin Yang Yunyan Zhang Weizhong Ding Yuwen Zhang Peijun Shen Yuding Zhou Yong Liu Shaoqing Huang Xionggang Lu 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2009年第4期407-414,共8页
The performance of LiNi/γ-Al2O3 catalysts modified by rare earth metal oxide (La2O3 or CeO2) packed on BCFNO membrane reactor was discussed for the partial oxidation of methane (POM) in coke oven gas (COG) at 8... The performance of LiNi/γ-Al2O3 catalysts modified by rare earth metal oxide (La2O3 or CeO2) packed on BCFNO membrane reactor was discussed for the partial oxidation of methane (POM) in coke oven gas (COG) at 875 ℃. The NiO/γ-Al2O3 catalysts with different amounts of La2O3 and CeO2 were prepared with the same preparation method and under the same condition in order to compare the reaction performance (oxygen permeation, CH4 conversion, H2 and CO selectivity) on the membrane reactor. The results show that the oxygen permeation flux increased significantly with LiNiREOx/γ-Al2O3 (RE = La or Ce) catalysts by adding the element of rare earth especially the Ce during the POM in COG. Such as, the Li15wt%CeO29wt%NiO/γ-Al2O3 catalyst with an oxygen permeation flux of 24.71 ml·cm^-2·min^-1 and a high CH4 conversion was obtained in 875 ℃. The resulted high oxygen permeation flux may be due to the added Ce that inhibited the strong interaction between Ni and Al2O3 to form the NiAl2O4 phase. In addition, the introduction of Ce leads up to an important property of storing and releasing oxygen. 展开更多
关键词 rare earth metal oxide oxygen permeation membrane reactor
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TUNGSTEN ELECTRODES CONTAINING THREE TYPES OF RARE EARTH OXIDES 被引量:5
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作者 Nie, Zuoren Zhou, Meiling +3 位作者 Chen, Ying Fan, Xiaowu Zhang, Jiuxing Zuo, Tieyong 《中国有色金属学会会刊:英文版》 EI CSCD 1999年第1期38-41,共4页
INTRODUCTIONWithincreasingdemandstothepropertyofweldingelectrodeandbeterknowledgeofThWelectrodematerial’sra... INTRODUCTIONWithincreasingdemandstothepropertyofweldingelectrodeandbeterknowledgeofThWelectrodematerial’sradioactivity,somes... 展开更多
关键词 rare earth oxideS TUNGSTEN electrode welding RIM Y 2O 3+La 2O 3+CeO 2
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Effects of flaky rare earth oxide additives on the high temperature performance of nickel electrodes 被引量:3
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作者 方庆 成艳 +4 位作者 简旭宇 朱磊 蔚海军 王忠 蒋利军 《Journal of Rare Earths》 SCIE EI CAS CSCD 2010年第1期72-78,共7页
Effects of flaky rare earth oxide additives including Er2O3,Tm2O3,and Yb2O3,Lu2O3 on high temperature and high rate discharge performance of nickel electrodes were investigated.The discharge efficiency at 0.2C reached... Effects of flaky rare earth oxide additives including Er2O3,Tm2O3,and Yb2O3,Lu2O3 on high temperature and high rate discharge performance of nickel electrodes were investigated.The discharge efficiency at 0.2C reached 96% at 60 oC for electrodes with 1 at.% flaky rare earth oxides.The high rate discharge performance for electrodes with flaky rare earth oxides were improved significantly,for example,discharge efficiency at 5C improved from 50% to 70%.The results showed that the end charging potential of the ... 展开更多
关键词 flaky rare earth oxides high temperature performance cyclic voltammograms nickel electrodes nickel-metal hydride batteries rare earths
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Study on rare earth/alkaline earth oxide-doped CeO_2 solid electrolyte 被引量:3
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作者 YAN Kai ZHEN Qiang Song Xiwen 《Rare Metals》 SCIE EI CAS CSCD 2007年第4期311-316,共6页
Five types of rare earth/alkaline earth oxide-doped CeO2 superfine-powders were synthesized by a low-temperature combustion technique. The relevant solid electrolyte materials were also sintered by pressureless sinter... Five types of rare earth/alkaline earth oxide-doped CeO2 superfine-powders were synthesized by a low-temperature combustion technique. The relevant solid electrolyte materials were also sintered by pressureless sintering at different temperatures. The results of X-ray diffraction and transmission electron microscopy showed that the grain size of the powders was approximately 20-30 nm, and rare earth/alkaline earth oxides were completely dissolved into ceria-based solid solution with fluorite structure. The electrical conductivities of the SmzO3-CeO2 system were measured by the ac impedance technique in air at temperatures ranging from 513-900℃. The results indicated that the ionic conductivities of Srno.2oCe0.8Ol.875 solid electrolyte increase with increasing sintering temperature, and the relationship between the conductivities and measuring temperature obeys the An'henius equation. Then the SmzO3-CeO2 material was further doped with other rare earth/alkaline earth oxide, and the conductivities improve with the effective index. 展开更多
关键词 doped ceria rare earth/alkaline earth oxide solid electrolyte CONDUCTIVITY effective index
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Effect of Roasting Conditions of Rich Cerium Rare Earth Carbonate on Crystallite Morphology and Polishing Ability of Ceria-Based Rare Earth Oxide 被引量:2
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作者 吴文远 李学舜 +2 位作者 陈杰 杨国胜 涂赣峰 《Journal of Rare Earths》 SCIE EI CAS CSCD 2007年第S1期125-128,共4页
The granule shape and crystal structure of the the ceria-based rare earth oxide which were roasted at 600~1050 ℃ for 2~6 h and then cooled in furnace, cooled out of furnace or cooled in water were studied by means ... The granule shape and crystal structure of the the ceria-based rare earth oxide which were roasted at 600~1050 ℃ for 2~6 h and then cooled in furnace, cooled out of furnace or cooled in water were studied by means of XRD and SEM. The results revealed that the rich cerium rare earth carbonate could be changed into the rare earth oxide which was a kind of sandwich made of globose granule whose diameter was between 0.5~3.0 μm after being roasted in 900 ℃ for 2 h. This kind of crystal lattice in rare earth oxide belonged to face-centered cubic lattice and its space between crystal surface {111} and {200} (viz. L111 and L200) would enlarge as the roasting temperature increasing. With increasing roasting temperature, L111 would rise straightly upward, and L200 would rise straightly upward when roasting time was 2~4 h but changed little when roasting time was 4~6 h. The glass-polishing experiments found that the polishing ability of the ceria-based rare earth oxide was the best as L111 was 43~53 nm and the L200 was 43~56 nm. 展开更多
关键词 polishing powder ceria-based rare earth oxide crystal lattice polishing ability rare earths
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Gasoline Sensor Based on Rare Earth-Doped Indium Oxide with Low Power Consumption 被引量:2
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作者 Xu Jiaqiang Wang Xiaohua +1 位作者 Wang Huanxin Shen Jianian 《Journal of Rare Earths》 SCIE EI CAS CSCD 2006年第3期319-319,共1页
Nanocrystalline indium oxide powders were prepared by microemulsion and then Y2O3 and Nd2O3 doped In2O3 were synthesized separately by impregnation and chemical co-deposition. The structure and morphology were charact... Nanocrystalline indium oxide powders were prepared by microemulsion and then Y2O3 and Nd2O3 doped In2O3 were synthesized separately by impregnation and chemical co-deposition. The structure and morphology were characterized by XRD and TEM, respectively. Gas sensing properties were tested at static state. The results show that homogeneous indium oxide nanopowder with main grain size of 20 nm can be obtained from microemulsion after sintered at 600 ℃ for 1 h. Pure indium oxide gas sensor has higher sensitivity to gasoline than that to ethanol, HCHO, C6H6, NH3, C4H10, but the selectivity is not as well as sensitivity. 展开更多
关键词 nanosized In2O3 micromulsion gas sensor yttrium oxide neodymium oxide rare earths
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Simultaneous Determination of Trace Rare Earth Elements and Other Elements in High Purity Terbium Oxide (Tb_4O_7) by ICP-AES After HPLC Separation Using P507 Resin 被引量:2
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作者 Wanjau Ruth Jiang Zu-cheng +3 位作者 Hu Bin Qin Yong-chao Wu Ying-liang Zhu Xia-shi 《Wuhan University Journal of Natural Sciences》 CAS 2002年第2期212-216,共5页
This article describes a new method for the simultaneous determination of trace rare earth elements (REEs) and non rare earth elements (NREEs) in high purity terbium oxide by ICP-AES after HPLC separation using P507 r... This article describes a new method for the simultaneous determination of trace rare earth elements (REEs) and non rare earth elements (NREEs) in high purity terbium oxide by ICP-AES after HPLC separation using P507 resin. The chromatographic separation of the analytes from the matrix using dilute nitric acid as mobile phase was studied. The experimental results showed that a favorable separation of trace metals (Cu and Gd) from the matrix (Tb) can easily be achieved by elution with dilute nitric acid within 25 min. The proposed method was applied to the determination of trace metals (Ca, Cu, Mg, Mn, Ni, Si, La, Ce, Pr, Nd, Sm, Eu and Gd) in high purity terbium oxide. The detection limits (DLs) for the analytes ranged from 0.4-4.0 μg\5g -1, and the recoveries are from 78%-105%. 展开更多
关键词 high purity terbium oxide trace impurities rare earth elements non rare earth elements P507 resin HPLC ICP-AES
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Morphology, chemical compositions and size distribution of rare earth oxides in pure iron 被引量:4
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作者 ShengiunZhang BoSong +2 位作者 XihuaLiu QingLin BiyanWang 《Journal of University of Science and Technology Beijing》 CSCD 2003年第2期30-33,共4页
The pure iron was melted and deoxidized by metallic Al and rare earth elements La, Ce and Y respectively at 1600℃ in a vertical resistance furnace. The morphology, chemical composition and size distribution of the in... The pure iron was melted and deoxidized by metallic Al and rare earth elements La, Ce and Y respectively at 1600℃ in a vertical resistance furnace. The morphology, chemical composition and size distribution of the inclusions in deoxidized liquid iron have been investigated by using of SEM and image-analysis techniques. The investigated results show that the deoxidation products in molten iron are complex inclusions of rare earth oxide or A12O3 combined with FeO finely distributed. The proper holding time and rapid cooling rate can make inclusions finer. La, Y and Al are more effective than Ce for obtaining finely distributed inclusions. 展开更多
关键词 rare earth element oxideS liquid iron size distribution
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Effects of Rare Earth Oxides on Viscosity,Thermal Expansion,and Structure of Alkali-Free Boro-Aluminosilicate Glass 被引量:2
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作者 侯延升 YUAN Jian +3 位作者 康俊峰 CUI Jingjing CHENG Jinshu CUI Jing 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2017年第1期58-62,共5页
Effects of rare earth oxides(Y2O3,La2O3,and Er2O3) on the viscosity,thermal expansion,and structure of alkali-free boro-aluminosilicate glasses were investigated by the rotating crucible viscometer,dilatometry and F... Effects of rare earth oxides(Y2O3,La2O3,and Er2O3) on the viscosity,thermal expansion,and structure of alkali-free boro-aluminosilicate glasses were investigated by the rotating crucible viscometer,dilatometry and FT-IR absorption spectra.The results showed that the melting temperature of alkali-free boroaluminosilicate glasses decreased from 1 697.55 to 1 662.59,1 674.37 and 1 640.87 ℃ with the introduction of 1 mol%La2O3,Y2O3 and Er2O3,respectively.However,the glass transition temperature Tg,dilatometric softening temperature T_d and coefficient of thermal expansion of alkali-free boro-aluminosilicate glasses increased when adding the rare-earth oxides.At high temperatures,incorporating rare earth oxides into glass resulted in the peak at about 1 085 cm^-1 towards lower wavenumber and the absorption band in the region of 850-1 260 cm^-1 broader,which indicated that rare earths acted as network modifiers and increased the numbers of non-bridging oxygen in the glass melts.However,the rare earths had an opposite effect and accumulated the glass structure at low temperatures near Tg. 展开更多
关键词 VISCOSITY STRUCTURE boro-aluminosilicate rare earth oxides
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Effects of various rare earth oxides on morphology and size of oxide dispersion strengthening(ODS)-W and ODS-Mo alloy powders 被引量:3
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作者 He ZHANG Zhi-bo LI +3 位作者 Xiao-chun DENG Ben CHEN Guo-hua ZHANG Kuo-Chih CHOU 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2022年第8期2665-2680,共16页
Ultrafine oxide dispersion strengthening(ODS)-Mo and ODS-W alloy powders containing different types of oxide nanoparticles were successfully synthesized by spraying method(solid−liquid mixing method)combined with the ... Ultrafine oxide dispersion strengthening(ODS)-Mo and ODS-W alloy powders containing different types of oxide nanoparticles were successfully synthesized by spraying method(solid−liquid mixing method)combined with the reductions with carbon black and hydrogen in sequence.It is concluded that the solution concentration and type of rare earth oxide have no effect on the grain size of ODS-Mo alloy powder,but have obvious effect on that of ODS-W alloy powder.The higher the concentration of rare earth solution is,the smaller the average grain size of ODS-W alloy powder is.Furthermore,compared with doping with CeO_(2),the grain sizes of reduction products of La_(2)O_(3) and Y_(2)O_(3) doped WO_(3) are relatively larger.Compared with the undoped case,there is almost no change for grain size of ODS-Mo alloy powder,while the grain size of ODS-W alloy powder becomes much larger.This is probably due to the appearance of the composite oxide(such as La_(2)WO_(6))formed by the reaction between tungsten oxide and rare earth oxides,which promotes the heterogeneous nucleation and growth of tungsten grains during the reduction process of ODS-W,while there is no complex oxide composed of molybdenum and rare earth oxides in the reduction process of ODS-Mo. 展开更多
关键词 grain size rare earth oxide oxide dispersion strengthened alloy W MO
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Roles of rare earth oxide additives in millimeter-wave sintering of AlN 被引量:2
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作者 Yukio Makino Takashi Yoshioka +2 位作者 Hiromi Nakano Toshiyuki Ueno Shoji Miyake 《Journal of Rare Earths》 SCIE EI CAS CSCD 2008年第2期141-145,共5页
Roles of rare earth oxide (RE2O3) additives in millimeter-wave(MM) sintering of AIN were investigated from the standpoints of phase diagram, heating characteristics of rare earth oxides, and morphology of intergra... Roles of rare earth oxide (RE2O3) additives in millimeter-wave(MM) sintering of AIN were investigated from the standpoints of phase diagram, heating characteristics of rare earth oxides, and morphology of intergranular oxide phase. In the millimeter-wave sintering of AIN, densification temperature decreased with the decrease of the ionic radius of rare earth ion and was closely related with the eutectic temperature in the RE2Oa-Al2O3 binary system. The lowest densification temperature in the millimeter-wave sintering of AIN with Yb2O3 additive was attributed to the largest heating rate of Yb2O3-Al2O3 binary oxide under millimeter-wave radiation. Furthermore, the lowest densification temperature could be attained while selecting the Yb2O3 content so as to form the intergranular phase with the eutectic composition in the Yb2O3-Al2O3 binary system. The result showed good agreement with the above mentioned during the sintering of Si3N4 with Yb2O3-Al2O3 additive. From TEM observation, it was verified that film-like intergranular oxide phase formed under millimeter-wave radiation was favorable for attaining high thermal conductivity in the Yb2O3 added AINs. 展开更多
关键词 MILLIMETER-WAVE rare earth oxide AIN Si3N4 rapid densification selective heating heating rate thermal conductivity morphology
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Determination of Trace Impurities of Rare Earth Elements in High Purity Yttrium Oxide by ICPMS 被引量:2
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作者 刘晶磊 童迎东 章新泉 《Journal of Rare Earths》 SCIE EI CAS CSCD 1995年第1期52-57,共6页
Determination of trace rare earth elements(REEs)in 99. 999% purity yttrium oxide using the inductively coupled plasma mass spectrometric technique (ICPMS) has been developed. Instrumental parameters and factors affeci... Determination of trace rare earth elements(REEs)in 99. 999% purity yttrium oxide using the inductively coupled plasma mass spectrometric technique (ICPMS) has been developed. Instrumental parameters and factors affecitng analytical results have been studied and then optimized.Samples are analyzed directly following an acid digestion without separation or preconcentration and with limit of detection of 0. 003~0. 02 ng/ml, precision of ±5. 4%(cofficient of variation)and recovery of 90~115%. Correction for isobaric interferences from oxide ions and hydroxide ions is made mathematically. Special internal standard procedures are used to compensate drift in metal:metal oxide ratios and sensitivity. The analytical results of several samples are accurate as compared with inductively coupled plasma atomic emission spectrometry (ICPAES) and spark source mass spectrometry (SSMS). 展开更多
关键词 ICPMS High purity yttrium oxide Determination of trace rare earth element
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