三氧化二铝-聚苯乙烯复合微球的制备

 以Al₂O₃-PS复合材料为原料,采用乳液微封装法制备出掺杂Al₂O₃的PS空心微球。三相溶液分别是两个水相：蒸馏水（W₁相）、5wt%PVA水溶液（W₂相）和3wt%Al₂O₃-PS溶液（O相,苯和三氯甲烷混合物作溶剂）。所得微球表面粗糙度低于50nm。     

掺杂4-苯基卟啉的聚苯乙烯／二氧化硅复合纳米微球的制备

采用溶胶-凝胶法,首先利用苯乙烯与3-甲基丙烯酰氧基丙基三甲氧基硅烷(KH-570)化学反应合成共聚前驱物,利用TEOS在一定的条件下水解与缩合,一步合成了有机-无机复合纳米微球。用扫描电镜、红外光谱对共聚物及复合纳米粒子进行了表征。将非水溶性发光材料四苯基卟啉掺杂其中,制备出荧光复合纳米粒子。该粒子表现出了良好的发光性能,染料泄漏与猝灭几乎为零,可以作为一种新型的高效率的生物标记材料。     

制备大直径无气泡聚苯乙烯空心微球

高品质聚苯乙烯（PS）空心微球是惯性约束聚变（ICF）实验用多层塑料微球靶的重要芯轴,常由乳液技术制备。针对由乳液技术制备的PS微球壳壁内容易形成气泡而且大直径微球制备困难的问题,实验研究了对壳壁内存在的气泡以及消除方法和制备大直径PS微球的制备技术。     

干凝胶炉法制备聚苯乙烯空心微球

研究了一步乳化法制备初始粒子的过程中相比及搅拌强度对初始粒子直径的影响 ,初步探讨了干凝胶炉内成球过程中 ,炉温、炉内气氛、压力等对聚苯乙烯 (PS)空心微球产率及同心度的影响。以分子量为 2 2万的聚苯乙烯制得了直径在 70～ 550μm的初始粒子 ,经乙醇浸泡后 ,制得了含 2 %质量分数发泡剂的干凝胶粒子 ,并在 Polymer-70 0干凝胶炉上制备出了外直径为 4 0 0～ 90 0 μm、壁厚为 2～1 0 μm、同心度≥ 95%的     

干凝胶炉法制备聚苯乙烯空心微球

研究了一步乳化法制备初始粒子的过程中相比及搅拌强度对初始粒子直径的影响,初步探讨了干凝胶炉内成球过程中,炉温、炉内气氛、压力等对聚苯乙烯(PS)空心微球产率及同心度的影响。以分子量为22万的聚苯乙烯制得了直径在70～550μm的初始粒子,经乙醇浸泡后,制得了含2%质量分数发泡剂的干凝胶粒子,并在Polymer-700干凝胶炉上制备出了外直径为400～900μm、壁厚为2～10μm、同心度≥95%的PS空心微球。     

制备大直径无气泡聚苯乙烯空心微球

 高品质聚苯乙烯（PS）空心微球是惯性约束聚变（ICF）实验用多层塑料微球靶的重要芯轴,常由乳液技术制备。针对由乳液技术制备的PS微球壳壁内容易形成气泡而且大直径微球制备困难的问题,实验研究了对壳壁内存在的气泡以及消除方法和制备大直径PS微球的制备技术。     

微封装法制备聚苯乙烯空心微球的改进

 主要介绍了密度匹配微封装技术，利用此项技术制备的聚苯乙烯空心微球 球形度好于99%，同心度好于98%。另外还对球壳内壁气泡问题及大直径球壳的制备进 行了讨论。     

微封装法制备聚苯乙烯空心微球的改进

主要介绍了密度匹配微封装技术,利用此项技术制备的聚苯乙烯空心微球 球形度好于99%,同心度好于98%。另外还对球壳内壁气泡问题及大直径球壳的制备进 行了讨论。     

制备高质量聚苯乙烯微球胶粒晶体的蒸发自组装法

建立了一种组装亚微米级聚苯乙烯微球的方法，称作蒸发自组装法.该方法是在一定温度下 ，聚苯乙烯微球随着分散介质的蒸发在悬浮液的气-液相界面处进行高效组装的过程.扫描电 子显微镜显示组装体为规则排列的密堆积面心立方结构.研究发现，气-液界面处生成的组装 体强烈地阻碍着分散介质的蒸发，单位时间内消耗的颗粒总数量随组装面积的增大而增加. 通过调整悬浮液的蒸发温度和组装面积，可以有效地控制悬浮液相浓度的变化，从而实现在 相浓度基本不变的情况下组装出高质量的聚苯乙烯胶粒晶体. 关键词： 蒸发自组装法 胶粒晶体 聚苯乙烯微球 三维有序大孔材料     

空心聚苯乙烯微球电沉积金工艺

采用自行设计的微球电沉积装置,建立了空心聚苯乙烯(PS)微球的电化学沉积金工艺。实验条件为：电源输出电压0.7~0.8 V,电流密度2.0 mA·cm-2,镀液温度45 ℃,阴极转速250 r·min-1,镀液流速7 mL·min-1·cm-2。在此工艺条件下制得的空心金微球对称性和厚度均匀性良好,表面粗糙度低于500 nm,微球表面沉积金速率约为6 μm·h-1。     

Thermoluminescence study of aluminum oxide doped with therbium and thulium

In this work, α-Al₂O₃ doped either with Tb³⁺ or Tm³⁺ was prepared by combustion synthesis techniques for thermoluminescent (TL) ionizing radiation dosimetry applications. In this method, the reactants (aluminum nitrate, urea and therbium or thulium nitrate) are ignited in a muffle furnace at temperatures as low as 500 °C. This synthesis route is an alternative technique to the conventional fabrication methods of materials based on α-Al₂O₃ (Czochralsky, Vernuil), where high melting temperatures and reducing atmospheres are required. After combustion, the samples were annealed at temperatures ranging from 1000 to 1400 °C for 4 h in order to obtain the pure α-phase structure and were then irradiated with a Co-60 gamma radiation source. The annealed samples present a well defined TL glow peak with a maximum at approximately 200 °C and linear TL response in the dose range 0.5–5 Gy. It was observed that a 0.1 mol% concentration of Tb³⁺ or Tm³⁺ and annealing at 1400 °C optimize the TL sensitivity. The highest sensitivity was found for Tm³⁺ doped samples which were approximately 25 times more sensitive than Tb³⁺ doped samples. These results strongly suggest that combustion synthesis is a suitable technique to prepare doped aluminum oxide material and that Tm³⁺ doped aluminum oxide is a potential material for TL radiation dosimetry.     

Temperature sensing performance of dysprosium doped aluminum oxide powders

Dy³⁺-doped Al₂O₃ powders were prepared by combustion synthesis. Down-converted luminescence lines peaked at 451 and 471, 572, 660, 708 and 752 nm were obtained under 355 nm pulsed laser irradiation for as-prepared Dy³⁺ doping concentrations of 0.5, 1.0 and 2.0 wt.%. The fact that the relative intensities of the 451 and 471 nm luminescence bands changed with the samples temperature allowed the use of these emission lines for temperature sensing. We found that the maximum sensitivity of the temperature sensor based on the luminescence intensity ratio of those transitions changed with Dy³⁺ doping concentration indicating different coupling strengths between the crystal field and the rare-earth.     

铈掺杂氧化铝薄膜的蓝紫色发光特性

应用中频反应磁控溅射技术制备了Al₂O₃:Ce³⁺的非晶薄膜.X射线光电子谱(XPS)检测显示薄膜中有Ce³⁺生成.这些薄膜的光致发光峰是在374nm附近,它来自于Ce³⁺离子的5d¹激发态向基态4f¹的两个劈裂能级的跃迁.发光强度强烈地依赖于薄膜的掺杂浓度,但发光峰位置不随掺杂浓度而变化.Ce³⁺含量和薄膜的化学成分是通过X射线散 关键词： 光致发光 2O₃')" href="#">Al₂O₃ 薄膜 稀土元素     

微乳液聚合制备纳米银/聚苯乙烯复合材料

采用柠檬酸钠为稳定剂、聚乙烯吡咯烷酮为分散剂,以水合肼还原银氨络离子制备出稳定的单分散胶态纳米银。以制得的纳米银溶胶,通过正相微乳液聚合,制备纳米银/聚苯乙烯复合材料。利用紫外-可见光(UV-Vis)吸收光谱研究了纳米银的光吸收特性,采用X射线衍射(XRD)和透射电镜(TEM)对产物的晶体结构、形貌及尺寸进行了分析。结果表明:所制得的银纳米颗粒属立方晶系,平均粒径约10 nm,且无团聚及氧化现象;聚合过程中,纳米银的晶体结构、形貌及尺寸未发生明显变化。凝胶渗透色谱(GPC)分析表明聚苯乙烯基体重均分子量达4.03106,分子量分布指数为1.21;热重-示差扫描量热(TG-DSC)分析表明所制备的复合材料具有优异的热稳定性。     

Silica doped tin oxide composite anodes for lithium-ion batteries

Silica doped tin oxide composites prepared by a sol gel method have been studied as negative electrode materials for lithium-ion batteries. The composite powders fired at 500 °C were analysed by means of XRD and SEM and showed that the composite consists of a blend of crystalline and amorphous structure with different particle size distribution. The electrochemical properties of this anode material were examined by charge-discharge measurements and cyclic voltammetry. The silica doped tin oxide composite anode, which was cycled between 0.1 to 2.0 V, showed a reversible capacity of 270 mAh/g. Paper presented at the International Conference on Functional Materials and Devices 2005, Kuala Lumpur, Malaysia, June 6 – 8, 2005.     

Plasmonic tuning of aluminum doped zinc oxide nanostructures by atomic layer deposition

Currently there is a strong interest in plasmonic materials operating in the near‐infrared (NIR), however, conventional metals such as gold and silver possess high optical losses in this region. In this work we demonstrate localized surface plasmon resonances (LSPRs) with low loss in the NIR region by utilizing atomic layer deposition to deposit thin films of aluminium doped zinc oxide onto silicon nanopillars created via nanopshere lithography. The deposited films have excellent conformality and the LSPRs can be tuned from the mid‐infrared to the NIR by controlling the doping concentration, deposition temperature and nanostructure morphology. (© 2014 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim)     

Preparation,characterization and application of Nano CdS doped with alum composite electrolyte

A new composite electrolyte has been developed for electrochemical application and studied in details. The system contains Alum doped with nanosize cadmium sulphide (CdS) particles in the desire ratio. The structural studies were carried out by using X-ray diffraction (XRD) as well as infrared spectroscopy (IR) which affirms the composite nature of the system. The electrical properties, including ion transport studies and complex impedance spectra confirm the ionic nature of sample as well as enhancement in ionic conductivity by CdS doping. The temperature dependence measurement confirms the Arrhenius nature of sample, which is commonly observed in the ionic composite system. The dielectric constant varies with temperature, and this data is used to calculate the number of charge carrier (n/n_o) contributing to conductivity and fits well with emf variation. A cell was fabricated by sandwiching the composite between graphite and stainless steel electrodes, which shows an emf of 7 mV.     

聚芳亚胺酮空心微球的制备

利用微流体技术和双重乳液技术对大直径聚芳亚胺亚胺酮空心微球的制备条件进行了讨论。完成了微球壁厚和直径的控制研究,并讨论了密度不匹配对微球质量的影响。获得了直径0.6～2.0 mm,壁厚5.0～20.0 μm的聚合物微球材料,并对微球制备过程中相分离对聚合物微球形貌的影响进行了分析,结果表明：在聚合物微球外表面易于进行spinodal分相,而在内表面易于进行binodal分相,因此微球内外表面具有不同的形貌结构。同批次制备微球中,平均直径±5%范围内的微球数占88%,球形度大于99%。     

The relationship of etching behavior and crystal orientation of aluminum doped zinc oxide films

Aluminum doped zinc oxide (AZO) transparent conducting films were dynamically deposited on corning glass substrates in an in-line sputtering system operated at mid-frequency sputtering mode with excitation frequency of 40 kHz. This study addressed the surface structure as well as the electrical and optical properties after wet-chemical etching. With the increase of substrate temperature, the dominant orientation of the as-deposited films changes from (0 0 2) to (1 0 3). After wet-chemical etching, due to the quick etching rate of the (0 0 2) plane relative to the (1 0 3) plane, the surface morphology of the films deposited at different temperatures show a transition from craterlike to granular surface morphology. The experimental results demonstrate that the crystal orientation of the as-deposited films plays an important role for the etching behavior of the films.