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Sm0.9Sr0.1AlO3-δ钙钛矿氧化物的固相反应合成和电学性能

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物理学报 2008年第7期57卷 4417-4423页

作者：向军王晓晖江苏科技大学数理学院

用固相反应法制备了Sm0.9Sr0.1AlO3-δ钙钛矿氧化物陶瓷.通过XRD,SEM和交流复阻抗谱以及氧浓差电池方法研究了样品的物相结构、微观形貌、电学性能及输运机理.结果表明,在1650℃烧结时,可以制备出单相的具有四方钙钛矿结构的氧化物Sm0.9... 详细信息

用固相反应法制备了Sm0.9Sr0.1AlO3-δ钙钛矿氧化物陶瓷.通过XRD,SEM和交流复阻抗谱以及氧浓差电池方法研究了样品的物相结构、微观形貌、电学性能及输运机理.结果表明,在1650℃烧结时,可以制备出单相的具有四方钙钛矿结构的氧化物Sm0.9Sr0.1AlO3-δ;1650℃烧结16h时的Sm0.9Sr0.1AlO3-δ样品具有最高的相对密度和电导率,其值分别为96.7%和1.3×10-2./cm(900℃),比未掺杂的SmAlO3的电导率大4个数量级左右,高温区电导活化能(T>670℃)小于低温区电导活化能(T<670℃);Sm0.9Sr0.1AlO3-δ在空气气氛中是一个氧离子和电子空穴的混合导体,氧离子迁移数在0.7左右,并随温度升高逐渐增加,氧离子电导活化能(0.95eV)大于空穴电导活化能(0.84eV),900℃时氧离子电导率为9.65×10-3S/cm.

关键词： SmAlO3 氧离子导电性混合导体活化能

Slope Debris Flows in the Wenchuan Earthquake Area

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Journal of Mountain science 2010年第3期7卷 226-233页

作者： LI Yanfu WANG Zhaoyin SHI Wenjing WANG Xuzhao state Key laboratory of Hydroscienee and {2. Tsinghua University Beijing 100084 China Beijing Institute of Geology for Mineral Resources Beijing 100012 China

Avalanches and landslides,induced by the Wenchuan Earthquake on May 12.2.08,resulted in a lot of disaggregated,solid material on slopes that could be readily mobilized as source material for debris *** triggered numerous slope debris flows with great damage to highways and rivers over the subsequent two *** debris flows(as opposed to channelized debris flows) are defined as phenomena in which high-concentration mixtures of debris and water flow down slopes for short distances to highways and river *** on field investigations and measurements of 19 slope debris flows,their main characteristics and potential mitigation strategies were *** rainfall intensity is the main triggering *** rainfall intensities for simultaneous occurrence of single,several and numerous slope debris flow events were 2. mm/day,30mm/day,and 90 mm/day,*** investigations also revealed that slope debris flows consist of high concentrations of cobbles,boulders and *** are two-phase debris *** liquid phase plays the role of lubrication instead of transporting *** particles collide with each other and consume a lot of *** velocities of slope debris flows are very low,and their transport distances are only several tens of *** debris flows may be controlled by construction of drainage systems and by reforestation.

关键词： Slope debris flow rainfall intensity Wenchuan Earthquake landslide avalanche

Photoresponsive organogel and organized nanostructures of cholesterol imide derivatives with azobenzene substituent groups

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Progress in Natural science:materials Intern{2. 2012年第1期22卷 64-70页

作者： Tifeng Jiao a,b,c,Yujin Wang a,Fengqing Gao a,Jingxin Zhou a,Faming Gao a a Hebei Key laboratory of Applied Chemistry,College of Environmental and Chemical engineering,Yanshan University,Qinhuangdao 066004,{2. b College of Chemistry & materials engineering,Wenzhou University,Wenzhou 32.02.,{2. c state Key laboratory of solid Lubrication,Lanzhou Institute of Chemical Physics,Chinese Academy of sciences,Lanzhou 730000,{2. Hebei Key laboratory of Applied Chemistry College of Environmental and Chemical Engineering Yanshan University Qinhuangdao 066004 China College of Chemistry & materials engineering Wenzhou University Wenzhou 325027 China state Key laboratory of {2. Lubrication Lanzhou Institute of Chemical Physics Chinese Academy of Sciences Lanzhou 730000 China

Two new cholesterol imide derivatives with azobenzene substituent groups have been *** compounds possess headgroups of hydrogen or methyl units,*** gelation test revealed that a subtle change in the headgroup of azobenzene segment produced a dramatic change in the gelation behavior of both *** compound with headgroups of hydrogen units only gelated N,N-Dimethylformamide(DMF),while the other compound with headgroups of methyl units cannot gelate any solvent tested *** DMF gel and solution of the gelator,the reversible photoisomerization transitions by irradiation with ultraviolet(UV) and visible light are investigated by UV-vis absorption spectra,Fourier transform infrared spectrometer,scanning electron microscope,atomic force microscope,and X-ray diffraction *** UV irradiation of the gel,trans-cis photoisomerization of the azobenzene groups occurs,the change in molecular polarity leads to the breaking of van der Waals interactions,resulting in the gel-sol *** gel can be recovered by the reverse cis-trans photoisomerization after exposure to visible *** and spectral studies reveal that the gelator molecules selfassemble into one-dimensional fibers,which further crossed-linked to form regular *** results afford useful information for the development of new versatile low molecular mass gelators and soft matter.

关键词： Organogel Cholesterol Azobenzene Photoisomerization Soft material

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垃圾焚烧飞灰胶凝活性初探

同济大学学报（自然科学版） 2003年第12期31卷 1444-1448页

作者：袁玲施惠生岳鹏同济大学混凝土材料研究国家重点实验室

飞灰是生活垃圾焚烧后烟气除尘器收下的物质 ,其主要成分属CaO—SiO2.—Al2.O3 —Fe2.O3 体系 ,与目前常用的高炉矿渣、粉煤灰等辅助性胶凝材料非常接近 .通过实验 ,研究了飞灰的物理性质以及其掺入水泥后对硬化水泥浆体力学性能和水化... 详细信息

飞灰是生活垃圾焚烧后烟气除尘器收下的物质 ,其主要成分属CaO—SiO2.—Al2.O3 —Fe2.O3 体系 ,与目前常用的高炉矿渣、粉煤灰等辅助性胶凝材料非常接近 .通过实验 ,研究了飞灰的物理性质以及其掺入水泥后对硬化水泥浆体力学性能和水化机理等的影响 ,初步探讨了飞灰作为辅助性胶凝材料利用的可行性 .研究表明 ,飞灰的水化反应活性较低 ,飞灰的掺入在一定程度上延缓了水泥的水化过程 ,但其水化可以形成适量钙矾石。

关键词：城市垃圾焚烧城市垃圾焚烧飞灰辅助性胶凝材料胶凝活性

Study on step friction characteristic of young people and children

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Study on step friction characteristic of young people and ch...

固相反应两步法制备纳米CeO_2.其机制研究

china 6th International Symposium on Tribology

作者： Jia LIxiao~(1 2. Zhang Yongzhen~1 Niu Yongping~1 Du Sanming~(1 3) 1 Key laboratory of material Tribology HenanUniversity of {2. and Technology 471003 2.department of Mechanical &Electrical engineering Luoyang Institute of {2. and Technology 47102. 3 state Key laboratory of solid Lubrication Lanzhou Institute of Chemical Physics 730000

＜正＞*** Accidents caused by slips and falls are serious safety problems in many countries[1,2.. Generally,slip possibility was decided by step characteristic while *** frictional characteristics of the shoe and the ...

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中国稀土学报 2004年第5期22卷 641-646页

作者：庄稼迟燕华吴修贤杨定明朱达川涂铭旌西南科技大学材料科学与工程学院化学系四川绵阳621002 四川大学材料科学与工程学院金属材料系四川成都610065

采用H2.2.4·2.2.和Ce(NO3)3·6H2.进行了低热固相反应。第一步合成前驱物Ce2.C2.4)3·10H2.,第二步加入模板剂NaCl,于800℃进行热分解反应。对分解产物进行了XRD测定和SEM,TEM分析。结果表明,得到了表面形貌为短节状、粒度分布均匀、... 详细信息

采用H2.2.4·2.2.和Ce(NO3)3·6H2.进行了低热固相反应。第一步合成前驱物Ce2.C2.4)3·10H2.,第二步加入模板剂NaCl,于800℃进行热分解反应。对分解产物进行了XRD测定和SEM,TEM分析。结果表明,得到了表面形貌为短节状、粒度分布均匀、无明显团聚现象、平均粒径在90nm左右的纳米粉体,同时对制备反应进行了热力学和动力学的初步研究。

关键词：固相反应纳米氧化铈前驱物模板剂反应机制稀土

化学共沉淀法制备的(Y_(1-x-y),Gd_y)_2._3∶xEu^(3+)红色荧光粉及其发光性能

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发光学报 2012年第3期33卷 247-252页

作者：蒲勇朱达川马明星韩涛赵聪四川大学材料科学与工程学院四川成都610065 重庆文理学院材料交叉学科研究中心重庆市高校微纳米材料工程与技术重点实验室重庆402168

用化学共沉淀法一次煅烧工艺合成了(Y1-x-y,Gdy)2.3∶xEu3+(x=0.06～0.10,y=0,0.2.～0.2.)系列红色荧光粉。用XRD、SEM和荧光分光光度计,对试样的晶体结构、表面形貌及发光性能进行表征。研究了Eu3+、Gd3+的掺杂浓度、表面活性剂的加入... 详细信息

用化学共沉淀法一次煅烧工艺合成了(Y1-x-y,Gdy)2.3∶xEu3+(x=0.06～0.10,y=0,0.2.～0.2.)系列红色荧光粉。用XRD、SEM和荧光分光光度计,对试样的晶体结构、表面形貌及发光性能进行表征。研究了Eu3+、Gd3+的掺杂浓度、表面活性剂的加入、煅烧温度对样品性能的影响。结果表明:样品为立方晶系;Gd3+的加入会使基体晶格发生畸变,晶胞参数增加,起到改善样品色纯度和发光效率的作用;最佳煅烧温度为900℃,比传统的高温固相法低500℃左右;所合成荧光粉的粒度主要分布在300～400 nm,结构比较松散;当x=0.08,y=0.2.时,最大发射峰(λem=613 nm)强度最大。所合成的Y1-x-y,Gdy)2.3∶xEu3+荧光粉是一种性能较好的PDP用红色荧光粉。

关键词： (Y1-x-y,Gdy)2.3∶xEu3+ 3D-PDP 化学共沉淀法红色荧光粉

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机械力固相化学反应合成纳米氧化铈

中国稀土学报 2003年第Z1期21卷 75-77页

作者：庄稼朱达川迟燕华杨定明涂铭旌四川大学材料科学与工程学院金属材料系四川成都610065 西南科技大学材料科学与工程学院化学系四川绵阳621002

采用氯化铈和草酸在低热条件下进行机械力固相化学反应,制备出前驱体草酸铈Ce2.C2.4)3·10H2.,通过热重和差热分析后,在400℃下分解该前驱体2.;分解产物经XRD,SEM和TEM分析测试,确认获得了粒度在80nm以下、表面形貌为球形、结构为立方... 详细信息

采用氯化铈和草酸在低热条件下进行机械力固相化学反应,制备出前驱体草酸铈Ce2.C2.4)3·10H2.,通过热重和差热分析后,在400℃下分解该前驱体2.;分解产物经XRD,SEM和TEM分析测试,确认获得了粒度在80nm以下、表面形貌为球形、结构为立方晶系的黄色CeO2.研究结果表明,用该法制备的CeO2.米粉体,具有简单、易行、效果好的特点。

关键词：机械力固相化学反应氧化铈纳米粉体

The electrical property of MnCo2.4 and its application for SUS 430 metallic interconnect

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science Bulletin 2010年第33期55卷 3835-3841页

作者： HUA Bin1,KONG YongHong1,LU FengShuang2.ZHANG JianFu2.PU Jian1 & LI Jian1 1 College of materials science and {2.,state Key laboratory of material Processing and Die & Mould Technology,Huazhong Univer-sity of science and Technology,Wuhan 430074,china 2.china Iron & Steel Research Institute Group,Beijing 100081,china

The conductivity of MnCo2.4 spinel,the best route to form the MnCo2.4 protective coating applied by the sol-gel process,and its effect on the intermediate temperature oxidation behavior of SUS 430 alloy,a typical material for the interconnect of solid oxide fuel cell(SOFC),was *** phase structure and surface morphology of the coating and surface oxides were characterized by XRD,SEM and EDS;the "4-probe" method was employed to determine the conductivity of MnCo2.4 spinel and the area specific resistance(ASR)of the surface *** conductivity of MnCo2.4 spinel is excellent,which is 2.orders of magnitude better than that of MnCr2.4 ***-term thermally cyclic oxidation at 750°C in SOFC cathode atmosphere and ASR measurement have shown that calcined in reducing atmosphere followed by pre-oxidation in the air is the best technique for forming the MnCo2.4 protective coating,which enhances the oxidation resistance,and improves the electrical conductivity and adherence of coated SUS 430 alloy *** a result,the MnCo2.4 spinel is the most potential candidate for SOFC metallic interconnect protective coating application.

关键词： solid oxide fuel cell MnCo2.4 oxidation kinetics area specific resistance