共查询到20条相似文献,搜索用时 78 毫秒
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采用醇盐水解法制备了掺杂GdBr3改性的纳米TiO2光催化复合材料,采用x射线衍射、透射电子显微镜、表面及孔隙度分析仪等测试技术分析和研究了改性TiO2粉体的晶相组成、形貌、比表面积及可见光光催化活性.结果表明,改性TiO2粉体在N2环境中经550℃煅烧2h后,粉体分散较好,TiO2仍为锐钛矿相,GdBr3/TiO2(摩尔比)为0.05的改性粉体在波长为420nm,照度为1200μw/cm2的可见光下照射12h后,对甲基橙的降解率可达70%,呈现出较好的可见光光催化活性. 相似文献
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二氧化硫脲为硫源制备硫掺杂二氧化钛及其光催化活性 总被引:2,自引:0,他引:2
以钛酸四丁酯为TiO2的前驱物,二氧化硫脲为掺杂硫的源物质,采用溶胶-凝胶法制备了掺硫改性的TiO2光催化剂。采用XRD对制备的掺硫二氧化钛结构进行了表征,探讨了溶胶-凝胶制备工艺、硫掺杂量及催化剂煅烧温度对该催化剂光催化活性的影响。结果表明,掺硫改性的TiO2经600℃煅烧后光催化活性有了明显提高,且硫的掺杂有一个最佳值,即二氧化硫脲的掺杂质量百分数为4%。经掺硫改性后的TiO2在可见光区具备更强的光催化活性,在波长不低于400nm的可见光作用下,对亚甲基蓝的4 h降解率最高可达89.5%。 相似文献
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太阳能与建筑一体化结合已经成为建筑节能领域的技术热点。针对与建筑一体化的太阳能热水系统和太阳能光伏系统进行了分析,阐述了国内外太阳能技术在建筑中应用的进展,探讨了国内外几个典型的太阳能建筑的技术特点,指出了我国太阳能建筑一体化目前存在的主要问题及其解决思路。 相似文献
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Solar energy has great potential as an alternative energy source, but variations in solar radiation require the use of additional energy sources to maintain a continuous drying process. We developed a process for drying kiwifruit using a solar dryer and an energy accumulation system with paraffin wax as phase change material. The final moisture content, total polyphenols, and antioxidant capacity were evaluated and compared with freeze drying. The analyzed experimental factors were kiwi slice thickness and the use or nonuse of fuzzy logic control systems to regulate the air flow through the devices. Critical moisture content, shrinkage, solar panel, and solar energy accumulator efficiencies were calculated. In addition, five empirical models were fitted to the drying curves. The solar panel showed an efficiency between 56 and 76%. The use of the fuzzy logic control system extended the period of available energy, thus prolonging the use of the solar panel and solar energy accumulator and using only 10% of the stored energy; otherwise, without the control system, 43% of the stored energy was used. The highest drying rates were achieved for kiwifruit slices 4?mm thick, using the solar dryer with the control system. The loss of polyphenols and antioxidant capacity were minimal for kiwifruit slices of thickness 8?mm without the control system. 相似文献
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传统的太阳能电池只能吸收能量大于半导体能隙的光子,能量小于半导体能隙的光子因为无法被吸收而被浪费掉,这一部分的能量损失高达50%。将上转换发光材料应用于太阳能电池中,将增加电池对能量小于半导体能隙的光子的吸收,极大提高太阳能电池的光电转换效率。稀土掺杂的上转换发光材料以其能够吸收红外光转换为可见光的独特性质,受到了国内外研究学者的广泛关注。这篇文章介绍了上转换发光材料的发光机制,以及近些年来稀土上转换发光材料在太阳能电池领域中的应用,包括硅基太阳能电池,染料敏化太阳能电池及钙钛矿太阳能电池。对稀土上转换发光材料在太阳能电池中应用所面临的困难以及潜在的解决方案做了总结与展望,有利于后续研究对稀土上转换发光材料在太阳能电池上的应用方向的探索,为提高太阳能电池的光电转化效率提供新思路,推进太阳能电池的大规模市场化应用。 相似文献