CuO—SnO2纳米晶粉料的Sol—Gel制备及表征

不用金属醇盐而以无起始物质，采用Ｓｏｌ－Ｇｅｋ法得到了平均晶粒尺寸为２１－２２ｎｍＣｕＯ掺杂的ＳｎＯ２粉料；运用Ｘ射线衍射（ＸＲＤ），差热－失重分析（ＤＴＡ－ＴＧ），透射电镜（ＴＥＭ）及ＢＥＴ比表面（ＳＡ）测定等分析手段对粉料进行了表征，实验表明，ＣｕＯ的掺杂抑制了ＳｎＯ２晶粒的生长，以无机盐为原料，采用Ｓｏｌ－Ｇｅｌ法制取ＳｎＯ２（ＣｕＯ）纳米级晶料是切实可行的，将有利于产业化。     

纳米TiO2粉晶的晶粒长大动力学及相转位动力学

用溶液胶－凝胶法制备了ＴｉＯ２纳米粉晶。对干凝胶做了ＤＴＡ、ＴＧ等热分析。利用ＸＲＤ微结构数据对粉晶长大行为及其相转位进行了分析了研究。结果表明,当热处理温度低于５００℃时,粉末粒径增长缓慢,而热处理温度高于５００℃时,粉末生长上变理论计算了晶粒长大激活能及相转位活化能,研究表明,高温区粒子生长激活能比低温区（５００℃以上）高出几倍,与粗晶粒相比,ＴｉＯ２的锐钛矿向金红石相转变的活化能要低得多。     

NiMn2O4纳米粉体的制备

用溶胶－凝胶法（ｓｏｌ－ｇｅｌ）合成ＮｉＭｎ２Ｏ４纳米级粉体，利用差热分析（ＤＴＡ），热失重（ＴＧ），Ｘ射线衍射（ＸＲＤ），透射电子显微镜（ＴＥＭ）等广阔博征合成过程及纳米粉体的结构，研究结果表明，ＮｉＭｎ２Ｏ４纳米粉体相合成温度比传统固相反应方法合成温度低大约３００℃，粉体的形状呈多面体形。     

CuO－SnO_2纳米晶粉料的Sol－Gel制备及表征

不用金属醇盐而以无机盐为起始物质，采用Ｓｏｌ－Ｇｅｋ法得到了平均晶粒尺寸为２１～２２ｎｍ，ＣｕＯ掺杂的ＳｎＯ_２粉料；运用Ｘ射线衍射（ＸＲＤ）、差热—失重分析（ＤＴＡ－ＴＧ）、透射电镜（ＴＥＭ）及ＢＥＴ比表面（ＳＡ）测定等分析手段对粉料进行了表征．实验表明，ＣｕＯ的掺杂抑制了ＳｎＯ_２晶粒的生长；以无机盐为原料，采用Ｓｏｌ－Ｇｅｌ法制取ＳｎＯ_２（ＣｕＯ）纳米级晶料是切实可行的，将有利于产业化．     

流态化CVD制备TiO_2－Al_2O_3复合粒子

本文探讨了流态化ＣＶＤ反应器中Ｔｉ（ＯＣ４Ｈ９）４水解制备ＴｉＯ２－Ａｌ２Ｏ３复合粒子新工艺，借助于ＳＥＭ、ＴＥＭ、ＢＥＴ、ＸＲＦ和ＥＰＭＡ等现代测试手段研究了复合粒子结构和包覆过程特征．结果表明，在流态化ＣＶＤ反应器中Ａｌ２Ｏ３超细颗粒以团聚体形式存在，ＴｉＯ２包覆量随Ｔｉ（ＯＣ４Ｈ９）４进料浓度升高而增加，但反应温度影响不大；在包覆过程中，同时存在成核和成膜，成核包覆使复合粒子比表面积增加，成膜包覆使复合粒子比表面积减小．     

流态化CVD制备TiO2—Al2O3复合粒子

本文探讨了流态化ＣＶＤ反应器中Ｔｉ（ＯＣ４Ｈ９）４水解制备ＴｉＯ２－Ａｌ２Ｏ３复合粒子新工艺，借助于ＳＥＭ、ＴＥＭ、ＢＥＴ、ＸＲＦ和ＥＰＭＡ等现代测试手段研究了复合粒子结构和包覆过程特征。结果表明，在流态化ＣＶＤ反应器中Ａｌ２Ｏ３超细颗粒以团聚体形式存在，ＴｉＯ２包覆量随Ｔｉ（ＯＣ４Ｈ９）４进料浓度升高而增加，但反应温度影响不大；在包覆过程中，同时存在成核和成膜，成核包覆使复合粒子比表面积增加，成     

新型BaO-TiO2-SiO2耐碱涂层在波特兰水泥中的稳定性

本文以扫描电镜、Ｘ射线荧光分析仪、二次中性粒子质谱仪和Ｘ射线衍射仪研究了以溶胶－凝胶法制备的ＢａＯ－ＴｉＯ２－ＳｉＯ２系涂层在波特兰水泥中的稳定性。结果表明，涂层以在较长时间内防止８０℃的饱和Ｃａ（ＯＨ）２溶液和波特兰水泥浸出液对基玻璃的侵蚀。以涂层的Ｅ－玻璃纤维增强水泥体，可有效地提高ＧＲＣ材料的耐久性。     

脉冲准分子激光CuO—SnO2薄膜沉积及其结构分析

采用脉冲准分子激光沉积（ＰＬＤ）技术，分别在Ｓｉ（１１１）单晶及玻璃基片上外延沉积了具有高α轴（２００）取向的ＣｕＯ掺杂的ＳｎＯ２薄膜，Ｘ射线衍射（ＸＲＤ）及透射电镜（ＴＥＭ扫描附件）分析表明：在Ｓｉ（１１１）片上沉４００－５００℃退火温度处理的薄膜，只有（２００）峰存在；当退火温度升高一６００－７００℃时，ＳｎＯ２的其余诸峰相应出现。薄膜呈多晶态，取向度降低，晶粒尺寸变大，晶粒分界明显，在玻璃基     

共沸蒸馏法制备超细氧化铝粉体及其表征

用改进的溶胶－凝胶法（ｓｏｌ－ｇｅｌ）制备了单分散纳米级Ａｌ_２Ｏ_３粉体,研究了不同干燥方法对产品粒子性能的影响．结果表明,共沸蒸馏法能够有效地对氢氧化铝凝胶脱水,防止了硬团聚体的形成．在１１５０℃的温度下煅烧,可制得尺寸分布均匀、呈球形的α－Ａｌ_２Ｏ_３超细粉体,其平均粒径为６８ｎｍ．以透射电镜（ＴＥＭ）、Ｘ射线衍射（ＸＲＤ）、热重（ＴＧ）、差热（ＤＴＡ）、比表面测定（ＢＥＴ）等手段对所得的超细Ａｌ_２Ｏ_３粉体进行了表征．     

Y2O3纳米晶的制备和表征

采用硬脂酸凝胶法制备了Ｙ２Ｏ３纳米晶，用傅立叶交换红外光谱（ＦＴＩＲ），热重－差热（ＴＧ－ＤＴＡ）对制备过程进行了表征。用Ｘ射线末衍射（ＸＲＤ），透射电子显策镜（ＴＥＭ）及ＢＥＴ比表面吸附对Ｙ２Ｏ３纳米晶的粒径和形貌进行一表征。在６００℃以上热处理得到立方晶系Ｙ２Ｏ３纳米晶，其粒径随热自理的上升而增大，形貌由球形变为立方形。粒径分布窄，无硬团聚现象产生，用傅立叶变换红外光谱（ＦＴＩＲ）对其谱学特性     

Effect of Ta nanobarrier in magnetron sputtering of Nd-doped SrBi2Ta2O9 thin films

SrBi2Ta2O9 (SBT) is a bismuth layered perovskite with attractive ferroelectric properties for random access memory applications. Our previous studies showed that Nd-doped SBT (SNBT) thin films exhibited an improved remnant polarization and reduced coercivity. This paper concentrates on the effect of Ta nanobarrier in between the SNBT and the Pt layers. Without the nanobarrier, severe bismuth diffusion is revealed by the secondary ion mass spectroscopy. However, with a nano layer (up to 2 nm) of Ta metal, the interfacial diffusion is effectively suppressed even at 800 degrees C. Details of the composition profiling, film crystallinity and remnant polarization are discussed in view of the nanobarrier thickness.     

Electrical properties of Li2O-La2O3-SiO2 electrode glasses after Ta2O5 doping and Ta implantation

Electrical conductivities, , of the Li₂O-La₂O₃-SiO₂ glasses were investigated as functions of Ta₂O₅ doping and Ta ion-implantation. A linear relationship between logarithm and the inverse of the sample temperature, T, was found in 2 to 4 mol% Ta₂O5 doped Li₂O-La₂O₃-SiO₂ glasses. The conductivity increases as Ta₂O₅ content increases at sample temperatures above 100°C. Fluences of 50 keV Ta ions per cm² from 5 × 10¹⁶ to 2 × 10¹⁷ were implanted into 0% and 2% Ta₂O₅ containing Li₂O-La₂O₃-SiO₂ glass samples. The activation energy of the conductivity was deduced from the relation between log and 1/T. It was found in implanted samples that the conductivity increased, but the activation energy and T _k–100 decreased, where T _k–100 is the sample temperature when the conductivity reaches 100 × 10^–1 S/cm. However, the Ta₂O₅ containing implanted samples show higher conductivities, lower activation energies and lower T _k–100. X-ray photoelectron spectroscopy (XPS) was used to study the structural modification introduced by implantation. Bridging oxygen (BO) and non-bridging oxygen (NBO), were observed in all samples. The changes in relative concentrations of BO and NBO before and after implantation clearly indicate the structure modification which results in the increase of the conductivity. It was clearly demonstrated in this study that both doping Ta₂O₅ and implanting Ta ions enhance the conductivity of Li₂O-La₂O₃-SiO₂ electrode glasses.     

Photoemission Spectroscopy of Ta2NiSe5

We report temperature-dependent angle-resolved photoemission spectroscopy measurement of Ta₂NiSe₅ which shows a semiconductor-semiconductor structural phase transition at around 330?K. Characteristically, flat band at the top of the valence band is observed, which is ascribed to the excitonic insulator effect. The top valence band shifts to higher binding energy and its bandwidth increases as the temperature decreases. As the system exceeds the transition temperature, the flat feature of the valence band weakens though the exciton fluctuations remain finite.     

Ta2N-TiW-Au复合导体研究

Ｔａ２Ｎ／ＴｉＷ／Ａｕ是目前国际上普遍采用的耐高温电阻／导带复合结构,对电阻温度系数（ＴＣＲ）的分析右确定溅射系统的工作点。总泄漏计算和驻贸气体分析（ＲＧＡ）可有效评价溅射气氛,提高ＴｉＷ／Ａｕ的可靠性,通过腐蚀液的比较,确定了合适的各膜层的腐蚀液。     

Surface morphology and dielectric properties of alkoxy-derived Sr2Ta2O7 and Sr2Ta, Nb2O7 thin films

Sr₂Ta₂O₇ and Sr₂(Ta, Nb)₂O₇ thin films were prepared from molecular structure-controled alkoxide solutions. The Sr₂Ta₂O₇ thin films initiated to crystallize at around 650 °C and showed random orientation. The surface topography developed was dependent on the solutions. In the thin films prepared from the ethanolic solution, grains formed at low temperatures. However, many small pores still remained and no grains were observed in the thin films prepared from the methoxyethanolic solution. In contrast, the 800 °C-annealed Sr₂(Ta, Nb)₂O₇ thin films showed the (0 k 0) orientation as in Sr₂Nb₂O₇ thin films. The dielectric constants and loss factors of the 750 °C-annealed Sr₂Ta₂O₇ and Sr₂(Ta_0.7Nb_0.3)₂O₇ thin films were around 90 and less than 0.05 at 100 kHz, respectively.     

Scintillation in anodic Ta2O5 films

The scintillation of anodic tantalum oxide was investigated by counting the number of breakdown events during anodization at a constant current density. A theory is developed which qualitatively explains the variation in the number of breakdown pulses with time and voltage for different current densities and different electrolyte resistivities. The theory also allows definition of a limiting anodization voltage which increases with the logarithm of the current density. Several experiments are presented which are in agreement with the theory.     

Formation of monodispersed Ta2O5 powders

The Ta₂O₅ powders synthesized by the hydrolysis of tantalum pentaethoxide, Ta(OC₂H₅)₅ in alcoholic solution were monodispersed fine oxide particles, which were a uniform, spherical shape, non-agglomerate, and had a narrow size distribution. They grew to 1.2m after ageing for 1 h after hydrolysis. Powder X-ray diffraction and differential thermal analysisthermogravimetric analysis showed the particles were amorphous and hydrated. These particles lost the water at 290° C and gave well-crystalline Ta₂O at 740° C. Throughout these thermal processes, the particle morphology was kept almost the same.     

Ta掺杂锐钛矿相TiO2的理论分析

采用基于密度泛函理论的第一性原理平面波超软赝势法,对Ta掺杂锐钛矿相TiO2的电子结构和光学吸收性质进行计算。结果表明,TiO2中掺杂Ta后,杂质能级与导带底混合,禁带宽度明显减小;杂质能级的引入和禁带宽度的减小使得Ta掺杂锐钛矿相TiO2光吸收在可见光范围内出现明显吸收增强。