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Conductivity of K_(10)H_3[Dy(SiW_4Mo_7O_(39))_2] Treated by Chemistry-Heated Diffusion of Sm and Gd Permeation 被引量:2
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作者 李中华 韦永德 +1 位作者 周百斌 王进福 《Journal of Rare Earths》 SCIE EI CAS CSCD 2003年第6期697-698,共2页
Chemistry-heated diffused permeation was used to treat POMs. ICP, IR, TG-DTA, XPS were used to characterize K_(10)H_3[Dy(SiW_4Mo_7O_(39))_2] and the sample. The result show that Sm and Gd can be permeated into the bod... Chemistry-heated diffused permeation was used to treat POMs. ICP, IR, TG-DTA, XPS were used to characterize K_(10)H_3[Dy(SiW_4Mo_7O_(39))_2] and the sample. The result show that Sm and Gd can be permeated into the body of this sample, chemical bonds forming between Sm and other components and the conductivity of K_(10)H_3[Dy(SiW_4Mo_7O_(39))_2] improves by 0 9356×10~4 times. 展开更多
关键词 inorganic chemistry POMS rare earths co-permeation CONDUCTIVITY rare earths
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Conductivity of K_ (11)[Sm(AlW_ (11)O_ 39H_2)_2]·21H_2O Treated by Chemistry-Heated Diffusion of Mixed Rare Earth Ce and La Permeation
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作者 李玲 韦永德 +2 位作者 周百斌 徐学勤 苏占华 《Journal of Rare Earths》 SCIE EI CAS CSCD 2005年第S1期113-116,共4页
The title compound was prepared and treated by high temperature gaseous mix rare earth permeation. ICP, IR, TG-DTA, XPS, XRD were used to characterize the title compound and the treated sample. The results confirm tha... The title compound was prepared and treated by high temperature gaseous mix rare earth permeation. ICP, IR, TG-DTA, XPS, XRD were used to characterize the title compound and the treated sample. The results confirm that Ce and La can be permeated into the body of the title compound. Four-probe method was used to measure the conductivities. A novel result that the conductivity of the permeated compound (δ=9.2×10 -3 S·cm -1)improved by 7.1×106 times than that of the title compound(δ=1.29×10 -9 S·cm -1) is received. 展开更多
关键词 POMS PERMEATION CONDUCTIVITY four-probe rare earths
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Conductivity of (NH4)3[CrMo6O24H6]·7H2O Treated by Nd Chemistry-Heated Diffused Permeation
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作者 Xin LI Zhonghua LI +3 位作者 Yuzhi GAO Maomao ZHAO Yuanru GUO Baibin ZHOU 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2005年第5期776-778,共3页
Rare earth co-permeation of (NH4)3[CrMo6O24H6]·7H2O was reported and the conductivity of (NH4)3[CrMo6O24H6] was improved by 6.734×10^9 times. X-ray fluorescence spectrometry (XRF), thermogravimetry-dif... Rare earth co-permeation of (NH4)3[CrMo6O24H6]·7H2O was reported and the conductivity of (NH4)3[CrMo6O24H6] was improved by 6.734×10^9 times. X-ray fluorescence spectrometry (XRF), thermogravimetry-differential thermal analysis (TG-DTA), X-ray diffraction (XRD) have been used to character (NH4)3[CrMo6O24H6]·7H2O and permeated sample. Experimental results showed that Nd could be permeated into the body of this sample and the XRD patterns showed great difference between (NH4)3[CrMo6O24H6]·7H2O and permeated sample. The structure of (NH4)3[CrMo6O24H6]·7H2O was destroyed and new compound MoN perhaps formed. 展开更多
关键词 Rare earths (NH4)3[CrMo6O24H6]·7H2O Chemistry-heated diffused permeation CONDUCTIVITY
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Simulation and optimization for synthetic technology of 2-chloro-4,6-dinitroresorcinol based on back-propagation neural network
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作者 史瑞欣 Huang Yudong 《High Technology Letters》 EI CAS 2007年第3期283-286,共4页
Back-propagation neural network was applied to predict and optimize the synthetic technology of 2-chloro-4,6-dinitroresorcinol. A model was established based on back-propagation neural network using the experimental d... Back-propagation neural network was applied to predict and optimize the synthetic technology of 2-chloro-4,6-dinitroresorcinol. A model was established based on back-propagation neural network using the experimental data of homogeneous design as the training sample set and the technological parameters were optimized by it. The optimal technological parameters are as follows: the reaction time is 4h, the reaction temperature is 80℃, the molar ratio of NaOH to 4,6-dinitro-1,2,3-trichlorobenzene is 5.5:1, the molar ratio of methanol to 4,6-dinitro-1,2,3- trichlorobenzene is 11:1, and the molar ratio of water to 4,6-dinitro-1,2,3-trichlorobenzene is 70:1. Under the optimal conditions, three groups of experiments were performed and the average yield of 2-chloro-4,6-dinitroresorcinol is 96.64%, the absolute error of it with the predicted value is -1.07%. 展开更多
关键词 2-chlom-4 6-dinitroresorcinol synthetic technology OPTIMIZATION back-propagation neural network model constructing
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Preparation of micro-arc oxidation coatings on magnesium alloy and its thermal shock resistance property 被引量:7
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作者 JIANG Zhaohua ZENG Xiaobin YAO Zhongping 《Rare Metals》 SCIE EI CAS CSCD 2006年第3期270-273,共4页
In the NaAlO2-Na2SiO3 compound system, the ceramic coatings were prepared on magnesium alloy by micro-arc oxidation. The morphology, phase composition, and thermal shock resistance of the ceramic coatings were studied... In the NaAlO2-Na2SiO3 compound system, the ceramic coatings were prepared on magnesium alloy by micro-arc oxidation. The morphology, phase composition, and thermal shock resistance of the ceramic coatings were studied by scanning electron microscope, X-ray diffraction and thermal shock tests, respectively. The results showed that the ceramic coating contains MgO, MgAl2O4, as well as a little amount of MgESiO4. The thickness of the ceramic coatings increases with the current density increasing, when the current density is 12 A·dm^-2, the thermal shock resistance of the produced ceramic coating is the best. The hardness of the ceramic coating is up to 10 GPa or so. 展开更多
关键词 micro-arc oxidation ceramic coatings thermal shock resistance magnesium alloy
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Effect of Black Plate on Corrosion Resistance of T5 Tinplate 被引量:5
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作者 HUANG Xing-qiao LI Ning JIANG Li-min LI De-yu 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2006年第2期59-64,共6页
The effect of black plate on corrosion resistance of T5 tinplate was studied by glow discharge spectrograph, X-ray diffractometer (XRD), stress tester, roughness tester and metallographic microscope. The result show... The effect of black plate on corrosion resistance of T5 tinplate was studied by glow discharge spectrograph, X-ray diffractometer (XRD), stress tester, roughness tester and metallographic microscope. The result shows that black plate influences corrosion resistance of T5 tinplate intensely. It also indicates that the increase of content of manganese, phosphorus, silicon and aluminum in black plate would reduce the corrosion resistance of T5 tinplate and the increase of degree of crystal orientation on (200) crystal face, |X-Y| value (internal stress difference within two orientation), roughness and exposure degree of iron grain after the same acid wash of black plate would enhance the corrosion resistance of T5 tinplate and the grain number of black plate has small effect on corrosion resistance of T5 tinplate. 展开更多
关键词 T5 tinplate black plate COMPONENT crystal orientation internal stress corrosion resistance
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Solubilization of Rock Phosphate in Liquid Culture by Fungal Isolates from Rhizosphere Soil 被引量:6
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作者 WANG Guang-Hua ZHOU De-Rui +2 位作者 YANG Qian JIN Jian LIU Xiao-Bing 《Pedosphere》 SCIE CAS CSCD 2005年第4期532-538,共7页
Rock phosphate (RP) is a low efficiency P fertilizer that is directly applied to the soil and can be solubilized by phosphate-solubilizing microorganisms (PSMs) in fermentation or soil conditions. This study inves... Rock phosphate (RP) is a low efficiency P fertilizer that is directly applied to the soil and can be solubilized by phosphate-solubilizing microorganisms (PSMs) in fermentation or soil conditions. This study investigated dynamic solubilization of 2 concentrations of rock phosphate in a liquid culture with different dosages of glucose by two fungal isolates,Aspergillus niger P39 and Penicillium oxalicum P66, from soybean and wheat rhizosphere soil. Although during the 20 day culture period A. niger P39 had a stronger ability to acidify the culture media than P. ozalicum P66, soluble P concentrations at glucose dosages of 30 and 50 g L^-1 with RP of 15 g L^-1 in the culture solution were much higher by P. oxalicum P66. The greater effectiveness of P. oxalicum P66 compared to A. niger P39 in the solubilization of RP was strongly associated with the production of organic acids. This study suggested that for RP solubilization the type rather than the concentration of PSM-produced organic acids was more important. 展开更多
关键词 Aspergillus niger organic acids Penicillium oxalicum phosphate solubilization rock phosphate
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Photocatalytic degradation of Rhodamine B under visible light with Nd-doped titanium dioxide films 被引量:6
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作者 WU Xiaohong SU Peibo LIU Huiling QI Lili 《Journal of Rare Earths》 SCIE EI CAS CSCD 2009年第5期739-743,共5页
Microporous titanium dioxide films were prepared by the sol-gel methods on glass substrates, using tetrabutyl titanate as source material. In order to absorb the visible light and increase the photocatalytic activitie... Microporous titanium dioxide films were prepared by the sol-gel methods on glass substrates, using tetrabutyl titanate as source material. In order to absorb the visible light and increase the photocatalytic activities, different concentrations of neodymium ions (Nd/Ti molar ratio was 0.5%, 0.7%, 0.9%, and 1.1% respectively) were added into the sol. X-ray diffraction (XRD), X-ray photoelectron spectros-copy (XPS), and atom force microscopy (AFM) were applied to characterize the modified films. A kind of typical textile industry pollutant (Rhodamine B) was used to evaluate the photocatalytic activities of the films under visible light. The results showed that the activities of the films were improved by doping Nd ions into the sol. 展开更多
关键词 titanium dioxide visible light doping ion PHOTOCATALYSIS Rhodamine B rare earths
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Preparation and Corrosion Resistance of Rare Earth Conversion Coatings on AZ91 Magnesium Alloy 被引量:7
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作者 许越 陈湘 +1 位作者 吕祖舜 李英杰 《Journal of Rare Earths》 SCIE EI CAS CSCD 2005年第5期555-558,共4页
The feasibility of forming pollution-free and environmentally benign Ce-based rare earth conversion coatings (short for RECCs) on AZ91 magnesium alloy to enhance corrosion resistance was studied. The effect of optim... The feasibility of forming pollution-free and environmentally benign Ce-based rare earth conversion coatings (short for RECCs) on AZ91 magnesium alloy to enhance corrosion resistance was studied. The effect of optimum processing parameters on corrosion resistance of RECCs, such as density of treating solution, temperature and time of coating formation were discussed. Protective performance of conversion coatings on magnesium alloy was evaluated by moisture/heating test, anodic polarization, etc. The results show that Ce-based RECCs under moisture/heating condition can remain intact, with high coverage and no obvious corrosion phenomenon. Corrosion potential increases and passive phenomenon occurs while current density decreases, therefore Ce-based RECCs can improve corrosion resistance of AZ91 magnesium alloy. The morphology of Ce-based RECCs prepared under optimum process through SEM observation is found to be a few particles coherent to the base coating, and the coating has no cracks and exhibits apparent corrosion resistance during corrosion courses of AZ91 magnesium alloy. 展开更多
关键词 metal materials magnesium alloy rare earth conversion coatings corrosion resistance rare earths
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Effects of Different Synthetic Parameters on Structure and Performance of LiMn_2O_4 by Adipic Acid-Assisted Sol-Gel Method 被引量:4
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作者 伊廷锋 王殿龙 +1 位作者 高昆 胡信国 《Journal of Rare Earths》 SCIE EI CAS CSCD 2005年第S1期209-213,共5页
The spinel lithium manganese oxide cathode materials were prepared by adipic acid-assisted sol-gel method at 350~900 ℃ in air. The effects of water content of solution, molar ratio between metal ion and adipic acid,... The spinel lithium manganese oxide cathode materials were prepared by adipic acid-assisted sol-gel method at 350~900 ℃ in air. The effects of water content of solution, molar ratio between metal ion and adipic acid, cooling rate, synthesis temperature and particle sizes on structure and electrochemical performance of LiMn_2O_4 are investigated by X-ray diffraction (XRD), and cyclic voltammetry (CV). The result shows that the structure and electrochemical performance of LiMn_2O_4 are greatly affected by synthesis condition, and the optimal synthesis condition is determined. Charge-discharge test reveals that the particle size and cooling rate have significant effects on the electrochemical performance of LiMn_2O_4 cathode materials. 展开更多
关键词 lithium ion battery SOL-GEL LiMn_2O_4 STRUCTURE electrochemical performance
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Composition and structure of coatings on Ti-6Al-4V alloy by micro-plasma oxidation in NaAlO2 solution 被引量:3
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作者 YAO Zhong-ping JIANG Zhao-hua SUN Xue-tong WU Zheng-dong ZHANG Xue-lin 《中国有色金属学会会刊:英文版》 CSCD 2004年第z1期162-165,共4页
Compound ceramic coatings on Ti-6Al-4V alloy were prepared for different time by pulsed bi-polar micro-plasma oxidation (MPO) in NaAlO2 solution. The phase composition was studied by XRD. And the electrochemical imped... Compound ceramic coatings on Ti-6Al-4V alloy were prepared for different time by pulsed bi-polar micro-plasma oxidation (MPO) in NaAlO2 solution. The phase composition was studied by XRD. And the electrochemical impedance spectra (EIS) of the coatings were measured to study the structure of the coatings, combined with the surface morphology. Using the proper EIS interpreting software, the "equivalent circuit" of the coatings was established, and meanwhile fitting values of equivalent element were obtained. The results show that the coating is composed of Al2 TiO5, α-Al2O3 and rutile TiO2, of which Al2 TiO5 is the main crystalline. Increasing the MPO time, the contents of Al2TiO5, rutile TiO2 and α-Al2O3 in the surface of the coating increase. And the EIS analysis and the surface morphology of the coatings illustrates the double-layer structure of the coatings, and the outer layer is loosen and the inner layer is compact. With the increase of the oxidizing time, the surface coarse degree of the coatings and the porosity of the outer layer of the coating are increased while the compactness of the inner layer of the coating is improved. 展开更多
关键词 MICRO-PLASMA OXIDATION ceramic COATINGS electrochemical impedance SPECTRA TI-6AL-4V alloy
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Surface Characteristics of Rare Earth Treated Carbon Fibers and Interfacial Properties of Composites 被引量:3
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作者 徐志伟 黄玉东 +2 位作者 宋元军 张春华 刘丽 《Journal of Rare Earths》 SCIE EI CAS CSCD 2007年第4期462-468,共7页
Effect of rare earth treatment on surface physicochemical properties of carbon fibers and interfacial properties of carbon fiber/epoxy composites was investigated, and the interfacial adhesion mechanism of treated car... Effect of rare earth treatment on surface physicochemical properties of carbon fibers and interfacial properties of carbon fiber/epoxy composites was investigated, and the interfacial adhesion mechanism of treated carbon fiber/epoxy composite was analyzed. It was found that rare earth treatment led to an increase of fiber surface roughness, improvement of oxygeaa-containing groups, and introduction of rare earth element on the carbon fiber surface. As a result, coordination linkages between fibers and rare earth, and between rare earth and resin matrix were formed separately, thereby the interlaminar shear strength (ILSS) of composites increased, which indicated the improvement of the interfacial adhesion between fibers and matrix resin resulting from the increase of carboxyl and carbonyl. 展开更多
关键词 carbon fiber/epoxy composite interfacial properties X-ray photoelectron spectroscopy rare earths
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Study on Properties of LSGM Electrolyte Made by Tape Casting Method and Applications in SOFC 被引量:3
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作者 张乃庆 孙克宁 +1 位作者 周德瑞 贾德昌 《Journal of Rare Earths》 SCIE EI CAS CSCD 2006年第z2期90-92,共3页
Solid oxide fuel cell is attracting more attention in recent years for its lower pollution emission and high energy convert efficiency. La0.9Sr0.1Ga0.8Mg0.2O3-δis a new kind of electrolyte for intermediate temperatur... Solid oxide fuel cell is attracting more attention in recent years for its lower pollution emission and high energy convert efficiency. La0.9Sr0.1Ga0.8Mg0.2O3-δis a new kind of electrolyte for intermediate temperature SOFC. In this paper, La0.9Sr0.1Ga0.8Mg0.2O3-δ(LSGM) was prepared by solid state reaction method and formed by tape casting process to make a planar electrolyte. The appropriate amount of the dispersive was obtained by viscosity test. The densities of sintered samples increase with the increasing sintering temperature. It was found that the relative density of electrolyte can approach the value of 95 % by the isostatic pressing treatment of the green tape. The average thermal expansion coefficient of the LSGM is 11 .4×10-6 /℃at temperature range (200 ~ 1200℃). Measurements of the current-voltage and power-current characteristics of the Hi-Air cell show that the open-circuit voltage is 1.067 V at 800℃, peak current density is 0.56 A·cm -2 and the maximum power output is 0.147 W·cm -2. 展开更多
关键词 solid oxide fuel cells LSGM electrolyte tape casting isotatic pressing rare earths
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Salt spray corrosion test of micro-plasma oxidation ceramic coatings on Ti alloy 被引量:3
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作者 HAO Guodong YAO Zhongping JIANG Zhaohua 《Rare Metals》 SCIE EI CAS CSCD 2007年第6期560-564,共5页
Ceramic coatings were prepared on Ti-6Al-4V alloy in NaAlO2 solution by micro-plasma oxidation (MPO). The salt spray tests of the coated samples and the substrates were carded out in a salt spray test machine. The p... Ceramic coatings were prepared on Ti-6Al-4V alloy in NaAlO2 solution by micro-plasma oxidation (MPO). The salt spray tests of the coated samples and the substrates were carded out in a salt spray test machine. The phase composition and surface morphology of the coatings were investigated by XRD and SEAM. Severe corrosion occurred on the substrate surface, while there were no obvious corrosion phenomena on the coated samples. The coatings were composed of Al2TiO5 and a little α-Al2O3 and mille TiO2, and the salt spray test did not change the composition of the coatings. The weight loss rate of the coatings decreased with increasing MPO time because of the increase in density and thickness of the coatings. The surface morphology of the coatings was influenced by salt spray corrosion test. Among the coated samples, the coating prepared for 2 h has the best corrosion resistance under salt spray test. 展开更多
关键词 micro-plasma oxidation ceramic coating salt spray corrosion test Ti alloy
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Fabrication and performance of La(0.8)Sr(0.2)MnO3/YSZ graded composite cathodes for SOFC 被引量:3
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作者 SUN Kening PIAO Jinhua +3 位作者 ZHANG Naiqing CHEN Xinbing XU Shen ZHOU Derui 《Rare Metals》 SCIE EI CAS CSCD 2008年第3期278-281,共4页
The performance of multi-layer (1 -x)La0.8Sr0.2MnO3/xYSZ graded composite cathodes was studied as electrode materials for intermediate solid oxide fuel cells (SOFC). The thermal expansion coefficient, electrical c... The performance of multi-layer (1 -x)La0.8Sr0.2MnO3/xYSZ graded composite cathodes was studied as electrode materials for intermediate solid oxide fuel cells (SOFC). The thermal expansion coefficient, electrical conductivity, and electrochemical performance of multi-layer composite cathodes were investigated. The thermal expansion coefficient and electrical conductivity decreased with the increase in YSZ content. The (1 -x)Lao.sSr0.EMnO3/xYSZ composite cathode greatly increased the length of the active triple phase boundary line (TPBL) among electrode, electrolyte, and gas phase, leading to a decrease in polarization resistance and an increase in polarization current density. The polarization current density of the triple-layer graded composite cathode (0.77 A/cm2) was the highest and that of the monolayer cathode (0.13 A/cm2) was the lowest. The polarization resistance (Rp) of the triple-layer graded composite cathode was only 0.182 Ω·cm2 and that of the monolayer composite cathode was 0.323 Ω·cm2. The power density of the triple-layer graded composite cathode was the highest and that of the monolayer composite cathode was the lowest. The triple-layer graded composite cathode had superior performance. 展开更多
关键词 MANGANITE composite cathode impedance spectrum triple phase boundary
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Powder electrochemical properties with different particle sizes of spinel LiAl_(0.05)Mn_(1.95)O_4 synthesized by sol-gel method 被引量:3
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作者 YI Tingfeng WANG Dianlong +1 位作者 GAO Kun HU Xinguo 《Rare Metals》 SCIE EI CAS CSCD 2007年第4期330-334,共5页
An Al-doped spinel lithium manganese oxide was prepared by the adipic acid-assisted sol-gel method at 800℃, and the cathode materials (Liml0.05Mnl.9504) with different particle sizes were obtained through ball mill... An Al-doped spinel lithium manganese oxide was prepared by the adipic acid-assisted sol-gel method at 800℃, and the cathode materials (Liml0.05Mnl.9504) with different particle sizes were obtained through ball milling. The effects of particle size on the electrochemical performance of LiAl0.05Mnl.9504 samples were investigated by differential thermal analysis and thermogravimetry, X-ray diffraction, galvanostatic charge-discharge test, cyclic voltammetry, and electrochemical impedance spectroscopy. The results indicate that all samples with different particle sizes show the same pure spinel phase and good crystal structure; LiAlo.osMnl.9504 with Dso = 17.3 μm shows better capacity retention; LiAlo.osMnl.gsO4 cathode materials with small particle size have a bigger resistance of charge transfer than the large one, and the particle size has significant effects on the electrochemical performance of Al-doped spinel LiMn2O4 cathode materials. 展开更多
关键词 lithium ion battery LiAl0.05Mn1.95O4 electrochemical properties particle size
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Sealing Glass of Barium-Calcium-Aluminosilicate System for Solid Oxide Fuel Cells 被引量:2
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作者 朴金花 孙克宁 +2 位作者 张乃庆 陈新冰 周德瑞 《Journal of Rare Earths》 SCIE EI CAS CSCD 2007年第4期434-438,共5页
Glass-ceramic materials were developed as a sealant in the solid oxide fuel cell (SOFC) in the temperature range of 800 -850 ℃. The glass materials were based on the glass and glass-ceramic in the BaO-CaO-Al2O3-SiO... Glass-ceramic materials were developed as a sealant in the solid oxide fuel cell (SOFC) in the temperature range of 800 -850 ℃. The glass materials were based on the glass and glass-ceramic in the BaO-CaO-Al2O3-SiO2-La2O3-B2O3 system. The thermal expansion coefficient (TEC) decreased with lower Ba^2+ content and higher Ca^2+ content, but the glass transition temperature and crystallization temperature increased greatly with an increase in Ca^2+ content and a decrease in Ba^2+ content, when the other components in the sealant were invariable. The TEC of the sealant with Ba^2+ content of 25.4% was 10.8 × 10^-6 K^- 1(temperature range from 25 to 850℃), and its softening temperature was 950 ℃. The TEC of the sealant accorded well with that of La0.9Sr0.1Ga0.5Mg0.2o3- 6(LSGM) with a mismatch of only 3%. The sealant had superior stability and compatibility with the LSGM electrolyte during the process of operation in SOFC. The weight loss of the sealant with Ba^2+ content of 25.4% was approfimately zero after heat-treated at 800℃ for 500 h in H2 and O2 atmosphere, respectively. 展开更多
关键词 solid oxide fuel cell GLASS-CERAMIC SEALANT compatibility rare earths
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Corrosion behavior of as-cast Mg_(68)Zn_(28)Y_4 alloy with I-phase 被引量:3
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作者 史菲 于元春 +2 位作者 郭学锋 张忠明 李瑛颖 《中国有色金属学会会刊:英文版》 CSCD 2009年第5期1093-1097,共5页
Mg68Zn28Y4 alloys with stable icosahedral quasicrystals(Zn60Mg30Y10)were prepared by cast method.By simulating the environment of ocean,the alloy was eroded in 3.5%(mass fraction)NaCl for 2,4 and 30 h.The microstructu... Mg68Zn28Y4 alloys with stable icosahedral quasicrystals(Zn60Mg30Y10)were prepared by cast method.By simulating the environment of ocean,the alloy was eroded in 3.5%(mass fraction)NaCl for 2,4 and 30 h.The microstructures of the samples and eroded alloys were analyzed by OM and SEM.The compositions and the quasiperiodic structures were identified respectively by EDS and TEM.And the corrosion potential and corrosion current density before and after immersion were measured by potentiodynamic polarization measurements in 3.5%NaCl.The results show that I-phases grow in the mode of conglomeration, piling and transfixion.The Mg7Zn3 matrix andα(Mg)solid solution are eroded badly,while W-phase is eroded partially.At the same time,the I-phases exhibit excellent corrosion resistance property.The resistance to corrosion of Mg68Zn28Y4 alloy is improved by increasing exposed I-phases.With adding element Y to Mg68Zn32 alloy,the corrosion current is decreased by one order of magnitude. And after the immersion of as-cast Mg68Zn28Y4 alloy for 30 h,the corrosion current density is reduced by two orders of magnitude compared with that of uneroded Mg68Zn32 alloy. 展开更多
关键词 合金相 腐蚀行为 腐蚀电流密度 二十面体准晶 扫描电镜分析 腐蚀电位 准周期结构 耐腐蚀性能
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Effect of erbium substitution on thermoelectric properties of complex oxide Ca_3Co_2O_6 at high temperatures 被引量:2
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作者 陆冬青 陈刚 +2 位作者 裴健 杨曦 线恒泽 《Journal of Rare Earths》 SCIE EI CAS CSCD 2008年第2期168-172,共5页
Polycrystalline particles of Ca3-xErxCo2O6 (x=0.0, 0.15, 0.3, 0.45 and 0.6) were synthesized using sol-gel method combined with Low Temperature Sintering procedure (LTS) to evaluate the effect of Er substitution o... Polycrystalline particles of Ca3-xErxCo2O6 (x=0.0, 0.15, 0.3, 0.45 and 0.6) were synthesized using sol-gel method combined with Low Temperature Sintering procedure (LTS) to evaluate the effect of Er substitution on the thermoelectric properties of Ca3Co2O6. The crystal structure and microstructure were investigated using X-ray diffraction, infrared spectroscopy and scanning electron microscope. The electrical conductivity and Seebeck coefficient of the complex oxides were measured from 300 to 1073 K. The results showed that all the sampies were p-type semiconductors. The electrical conductivity increased with the increase in temperature. Er substitutions at Ca site affected carrier concentrations and carder mobility, resulting an increase in Seebeck coefficient and decrease in electrical conductivity. The power factor of Ca2.85Er0.15Co2O6 reached 10.66 μw/mK^2 at 1073 K. 展开更多
关键词 Ca3Co2O6 thermoelectric properties rare earth substitution cobalt oxide rare earths
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Effects of La_(0.8)Sr_ (0.2)Mn(Fe)O_(3-δ) Protective Coatings on SOFC Metallic Interconnects 被引量:2
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作者 付长璟 孙克宁 周德瑞 《Journal of Rare Earths》 SCIE EI CAS CSCD 2006年第3期320-326,共7页
SUS430 (16% - 17% (mass fraction) Cr) can be used as interconnects for solid oxide fuel cells (SOFCs) that operate at lower temperatures ( 〈 800 ℃ ). However, oxidation of steel can occur readily at elevated... SUS430 (16% - 17% (mass fraction) Cr) can be used as interconnects for solid oxide fuel cells (SOFCs) that operate at lower temperatures ( 〈 800 ℃ ). However, oxidation of steel can occur readily at elevated temperatures leading to the formation of Cr2O3 and spinel (Fe3O4) and thus greatly degrades the performance of the fuel cell. The aim of this work was to reduce oxide growth, in particular, the Cr2O3 phase, through the application of La0.8Sr0.2MnO3-δ (LSM2O) and La0.8Sr0.2FeO3-δ(LSF20) coatings by atmospheric plasma spraying technology (APS). Oxide growth was characterized by using X-ray diffraction (XRD), scanning electron microscopy (SEM) with an energy dispersive X-ray (EDX) analyzer. During oxidation of fifty 20 h cycles at 800 ℃ in air, the samples with coatings remained very stable, whereas significant spallation and weight loss were observed for the uncoated steel. LSF20 presents apparently advantages in reducing oxidation growth, interface resistance and inhibition of diffusion of chromium. After exposure in air at 800 ℃ for 1000 h, the interfacial resistance of LSF20-coated alloy is lowered by more than 23 times to that of LSM20-coated layer. 展开更多
关键词 plasma spraying solid oxide fuel cells metallic interconnects COATINGS rare earths
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