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Rare earth(Y, La and Nd) doped TiO2 thin films were prepared on glass slides by sol-gel method. The photocatalytic decomposition of methylene blue in aqueous solution was used as a probe reaction to evaluate their photocatalytic activities. The effects of hydroxyl groups on hydrophilic and photocatalytic activities were investigated by means of techniques such as X-ray diffraction(XRD), atomic force microscopy(AFM), Fourier transform infrared(FTIR), optical contact angle, UV-Visible spectroscopy and VIS spectroscopy. The results showed that an appropriate doping of rare earth could cause the TiO2 lattice distortion, inhibited phase transition from anatase to rutile, accelerated surface hydroxylation and produced more hydroxyl groups, which resulted in a denser surface and smaller grains(40–60 nm), and a significant improvement in the hydrophilicity and photoreactivity of TiO2 thin films. The optimal content of rare earth was between 0.1 wt.% and 0.3 wt.%. Moreover, the modification mechanism of rare earth doping was also discussed. 相似文献
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本文在完成单元圆极化微带天线设计和馈电网络等相关问题的基础上,设计了一个16单元的2.45GHz圆极化微带天线阵,用电磁仿真软件Ansoft HFSS完成天线仿真设计,优化了天线的性能,最后加工成实物天线。通过微波暗室对实物天线参数测试,实测结果与仿真结果基本一致。天线安装在有源RFID系统中,读卡范围得到有效控制,效果达到满意。此天线产品成本低、加工简单、易于生产组装,已经批量生产,并获得了国家实用新型专利。 相似文献
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采用水热法合成了石墨烯-TiO2纳米管复合材料,通过扫描电镜(SEM)、透射电镜(TEM)、X射线衍射(XRD)、傅里叶变换红外光谱(FT-IR)、紫外-可见漫反射(DRS)表征复合催化剂的微观形貌、结构和光学特性。以H2PtCl6为前驱体,对复合材料进行Pt负载,C2H5OH/H2O溶液为反应液,在紫外光和太阳光下考察其产氢活性,实验结果表明,石墨烯的负载量为5%(质量分数)时催化剂的产氢活性最高,紫外光下和太阳光下反应5h,产氢量分别达到1069.299、3712.789μmol,远高于同等条件下P25的产氢活性。 相似文献
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Pure and La-doped TiO2 thin films were prepared on glass by sol-gel method using tetrabutyl titanate as Ti precursors. Their chemical composition, structure and properties were characterized by X-ray d... 相似文献
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以羧甲基壳聚糖、N,N-二甲基十六烷基叔胺以及丙烯酸为原料合成了一种新型的pH响应性两亲性纳米材料,利用FT-IR对其结构进行了表征。该纳米材料在水溶液中能够自发形成具有壳-核结构的纳米胶束,临界胶束浓度为95mg/L,不同pH条件下粒径分布有较大差异,表面Zeta电位均为正。以维生素D3为模型分子,测得其对VD3的包封率达到57.3%,同时考察了该纳米胶束包裹VD3在不同pH条件下的释放行为,结果显示在人工模拟胃液(SGF)中累积释放量最低(42.1%),人工模拟肠液(SIF)中最高(69.2%)。该纳米胶束的pH响应性行为表明其适宜作为VD3以及其他食品活性成分的潜在纳米生物活性载体。 相似文献