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Synthesis of yttrium oxide Nanocrystal via Solvothermal Process

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Journal of Rare Earths 2006年第z2期24卷 47-50页

作者：郭煌洪樟连张世张朋越樊先平 Department of Materials Science and Engineering Zhejiang University

Y2O3 nanomaterials have been widely used in transparent ceramics and luminescent devices. Recently there are many studies focusing on controlling the size and morphology of Y2O3 in order to obtain better materials performance. In present study, yttrium oxyhydroxide precursor was synthesized via a facile solvothermal process through the dissolution-re-crystallization mechanism of Y2O3 raw powders in the ethylenediamine solvent, then nanosized yttrium oxide crystal was prepared from the precursor through post heat treatment process. The effects of solvothermal treatment temperature, holding time, solvent kinds and post heat treatment parameters on crystalline structure, grain shape and size of nanocrystal were investigated by XRD, TEM and TGA-DTA measurements. TEM images reveal that the morphology of product after post heat treatment at 460℃for 12 h is rice-like nanocrystal. XRD shows that this product is pure cubic Y2O3 cphase. Present study reveals that high purity Y2O3 with rice-like morphology can be easily prepared with average size around 30 nm under suitable post heat treatment parameters. In addition, the effects of solvents such as water and ethanol etc. on the crystal structure and morphology were also investigated. It is suggested that dissolution-recrystallization process may be the main mechanism for the formation of nano-sized YOOH precursors under solvothermal reaction condition, and the ethylenediamine solvent is likely to play an important role in controlling the transformation process of yttria precursors to the Y2O3 nanocrystal.

关键词： yttrium oxyhydroxide yttrium oxide nanocrystal solvothermal process rare earths

Investigation of thermal radiation effect on optical dome of sapphire coated yttrium oxide

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Science Bulletin 2016年第10期61卷 801-810页

作者： Yuanchun Liu Zhiwei Hua Yurong He Jiaqi Zhu Jiecai Han School of Energy Science and Engineering Harbin Institute ofTechnology Harbin 150001 China College of Aerospace Science and Engineering NationalUniversity of Defense Technology Changsha 410000 China School of Astronautics Harbin Institute of TechnologyHarbin 150001 China

Compared to traditional optical domes, domes of sapphire coated with films can effectively reduce emissivity and increase transmittance. The purpose of this work is to investigate the thermal radiation effect on sapphire optical dome coated with yttrium oxide by a radio frequency mag- netron sputtering method. The emissivity of sapphire coated with Y203 films is studied by both numerical and experi- mental methods. The results indicate that the emissivity of sapphire substrate is reduced effectively with increasing the thickness of the Y203 film. In addition, a finite element model is developed to simulate the radiation intensity of the optical dome. The thermal responses indicate that the max- imum temperature is reduced apparently compared with the uncoated sapphire as Y203 film thicknesses increase. The average irradiance distribution at different film thicknesses with time shows that the self-thermal radiation disturbance of sapphire optical dome delays 0.93 s when the thickness of Y203 film is 200μm, which can guarantee the dome works properly and effectively even in a harsh environment.

关键词： yttrium oxide Sapphire substrate Apparent emissivity Thermal radiation effect

Study on phosphating treatment of aluminum alloy:role of yttrium oxide

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Journal of Rare Earths 2009年第3期27卷 469-473页

作者：张圣麟 College of Chemistry and Environmental Science Henan Normal University

Zinc phosphate coatings formed on 6061-Al alloy, after dipping in phosphating solutions containing different amounts of Y2O3（yttrium oxide）, were studied by scanning electron microscopy （SEM）, X-ray diffraction （XRD） and electrochemical measurements. Significant variations in the morphology and corrosion resistance afforded by zinc phosphate coating were especially observed as Y2O3 in phosphating solution varied from 0 to 40 mg/L. The addition of Y2O3 changed the initial potential of the interface between aluminum alloy substrate and phosphating solution and increased the number of nucleation sites. The phosphate coating thereby was less porous structure and covered the surface of aluminum alloy completely within short phosphating time. Phosphate coating was mainly composed of Zn3（PO4）2·4H2O （hopeite） and AlPO4（aluminum phosphate）. Y2O3, as an additive of phosphatization, accelerated precipitation and refined the gain size of phosphate coating. The corrosion resistance of zinc phosphate coating in 3% NaCl solution was improved as shown by polarization measurement. In the present research, the optimal amount of Y2O3 was 10-20 mg/L, and the optimal phosphating time was 600 s.

关键词： yttrium oxide zinc phosphate coating aluminum alloy nucleation agent accelerator rare earths

Synthesis and Characterization of Large Surface Area yttrium oxide by Precipitation Method

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Journal of Rare Earths 2004年第6期22卷 771-774页

作者：崔大立龙志奇张顺利崔梅生黄小卫 Grirem Advanced Materials Corporation Limited General Research Institute for Non-Ferrous Metals Beijing 100088 China

The method for preparing yttrium oxide with large specific surface area was introduced. By means of BET, SEM, TG and DTA analysis, the effects of precipitant, stirring velocity, non-RE impurity in solution, calcination temperature, on the surface area were studied respectively. The Y_2O_3 sample with specific surface area of more than 60 m^2·g^(-1) and L.O.I less than 1% was prepared in the suitable precipitation condition and calcinations temperature when the ammonia used as precipitant. The SEM shows that the Y_2O_3 prepared with large surface area is the aggregation of about 50 nm particles.

关键词： surface area yttrium oxide morphology precipitation method rare earths

Thermal, Mechanical and Electrical Properties of the PEO-based Solid Polymer Electrolytes Filled by yttrium oxide Nanoparticles

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Journal of Wuhan University of Technology(Materials Science) 2012年第3期27卷 495-500页

作者：梁桂杰 Research Center for Materials Science & Engineering Xiangfan University College of Materials Science & Engineering Xi'an Jiaotong University

The novel composite lithium solid polymer electrolytes （SPEs） composed of polyethylene oxide （PEO） matrix and yttrium oxide （Y2O3） nanofillers were prepared by a solution casting method. The crystal morphology of the SPEs was characterized by polarized optical microscope （POM） and wide-angle X-ray diffraction （WAXD）. The induced nucleation and steric hindrance effects of Y2O3 nanofillers result in the increased amount as well as decreased size of PEO spherulites which are closely related to the crystallinity of the SPEs. As the Y2O3 contents increase from 0 wt% to 15 wt%, the crystallinity of the SPEs decreases proportionally. The thermal, mechanical and electrical properties of the SPEs were investigated by thermal gravimetric analysis （TGA）, dynamic mechanical analysis （DMA） and AC impedance method, respectively. The physical properties including thermal, mechanical and electrical performances, depending remarkably on the polymer-filler interactions between PEO and Y2O3 nanoparticles, are improved by different degrees with the increase of Y2O3 contents. The （PEO）21LiI/10 wt%Y2O3 composite SPE exhibits the optimal room-temperature ionic conductivity of 5.95×10-5 Scm-1, which satisfies the requirements of the conventional electrochromic devices.

关键词： solid polymer electrolytes yttrium oxide thermostability mechanical property ionic conductivity

Synthesis and Characterization of Large Surface Area yttrium oxide by Precipitation Method

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Synthesis and Characterization of Large Surface Area Yttrium...

Interaction mechanism between BaZrO_(3)/Y_(2)O_(3) refractory and Ti_(2)Ni alloy melts

2004国际稀土研究与应用研讨会（包头）

作者：崔大立龙志奇张顺利崔梅生黄小卫 Grirem Advanced Materials Corporation Limited General Research Institute for Non-Ferrous Metals Beijing 100088 China Grirem Advanced Materials Corporation Limited General Research Institute for Non-Ferrous Metals Beijing 100088 China Grirem Advanced Materials Corporation Limited General Research Institute for Non-Ferrous Metals Beijing 100088 China Grirem Advanced Materials Corporation Limited General Research Institute for Non-Ferrous Metals Beijing 100088 China Grirem Advanced Materials Corporation Limited General Research Institute for Non-Ferrous Metals Beijing 100088 China

关键词： surface area yttrium oxide morphology precipitation method rare earths

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Journal of Iron and Steel Research International 2024年第6期31卷 1376-1388页

作者： Xiao Hou Guang-yao Chen Jian Liu Ming-rui Lv Fei-hai Yu Qi-sheng Feng Rong-bin Li Xiong-gang Lu Chong-he Li State Key Laboratory of Advanced Special Steel and Shanghai Key Laboratory of Advanced Ferromeallurgy and School of Materials Science and Engineering Shanghai UniversityShanghai 200072China Shanghai Special Casting Engineering Technology Research Center Shanghai 201605China Zhejiang Institute of Advanced Materials Shanghai UniversityJiashan 314100ZhejiangChina School of Materials Science and Engineering Shanghai DianJi UniversityShanghai 201306China

The titanium alloys with highly chemical activity require stable crucible refractories that can withstand the erosion of alloy *** phase composition and microstructure are crucial factors that affect the stability of the refractory *** effect of Y_(2)O_(3) on the composition and microstructure of BaZrO_(3) crucible was systematically investigated,and the improved mechanism of the stability of BaZrO_(3)/Y_(2)O_(3) crucible was clarified in comparison with the BaZrO_(3) *** results showed that the erosion layer thickness of the BaZrO_(3)/Y_(2)O_(3) crucible was only 63μm,which was far less than that in the BaZrO_(3) crucible(485μm),and the erosion layer in the BaZrO_(3)/Y_(2)O_(3) crucible also exhibited a higher density than that in the BaZrO_(3) *** the sintering,Y_(2)O_(3) could improve the densification of the BaZrO_(3) crucible due to the solid solution effect between Y_(2)O_(3) and ZrO_(2),which also caused the evaporation of BaO,resulting in the generation of a Y_(2)O_(3)(ZrO_(2))film on the surface of the ***,the Y_(2)O_(3)(ZrO_(2))had higher thermodynamic stability than Y_(2)O_(3),confirming that the BaZrO_(3)/Y_(2)O_(3) crucible with high density exhibited a superior erosion resistance to titanium *** dual-phase structure provides a strategy to design a long-life and stable refractory for melting titanium alloys.

关键词： Barium zirconate yttrium oxide Dual-phase refractory Titanium alloy Interaction

Microstructure and electrical properties of Y_2O_3-doped ZnO-based varistor ceramics prepared by high-energy ball milling

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Journal of University of Science and Technology Beijing 2007年第3期14卷 266-270页

作者： Hongyu Liu Xueming Ma Dongmei Jiang Wangzhou Shi College of Science Wuhan University of Science and Technology Wuhan 430081 China Department of Physics East China Normal University Shanghai 200062 China

Y2O3-doped ZnO-based varistor ceramics were prepared using high-energy ball milling （HEBM） and low-temperature sin- tering technique, with voltage-gradient of 1934-2197 V/mm, non-linear coefficients of 20.8-21.8, leakage currents of 0.59-1.04 μA, and densities of 5.46-5.57 g/cm3. With increasing Y2O3 content, the voltage-gradient increases because of the decrease of ZnO grain size; the non-linear coefficient and the leakage current improve but the density decreases because of more porosity; the donor con- centration and density of interface states decrease, whereas the barrier height and width increase because of the acceptor effect of Y2O3 in varistor ceramics.

关键词： inorganic materials electrical properties high-energy ball milling varistor microstructure low-temperature sintering zinc oxide yttrium oxide

Preparation and optical properties of Y_2O_3/SiO_2 powder

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Rare Metals 2011年第1期30卷 33-38页

作者： SHEN Xiaoyi ZHAI Yuchun School of Materials and Metallurgy Northeastern UniversityShenyang 110819China

Y（NO3）3 and NH3·H2O were used as a raw materials,and nano-Y2O3 powder was successfully synthesized by a precipitation *** TEOS as a raw material,SiO2 powder was successfully prepared by a alkoxide-hydrolysis method,and a Y2O3/SiO2 composite powder was obtained by *** Y2O3,SiO2,and Y2O3/SiO2 powders were characterized using X-ray diffraction（XRD）,scanning electron microscopy（SEM）,and Fourier transform infrared spectrophotometer（FT-IR）;the Y2O3 and Y2O3/SiO2 powders were further examined by photoluminescence（PL） *** results indicated that the Y2O3 powder had a body-centered cubic structure with an average size of 35 nm,while the SiO2 powder was amorphous,with an average size of 145 nm and a narrow size *** PL spectra of the Y2O3 and Y2O3/SiO2 powders showed that their wavelength of emission spectra were 585 nm,while their wavelength of excitation spectra were in the range of 240-260 *** optical properties of the Y2O3/SiO2 powder were identical to the Y2O3 powder.

关键词： powders composite materials yttrium oxide silicon oxide optical properties