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排序方式: 共有604条查询结果,搜索用时 9 毫秒
591.
多孔TiO2薄膜的表面微结构对甲基橙光催化脱色的影响 总被引:32,自引:0,他引:32
从含聚乙二醇的钛醇盐溶胶前驱体出发,通过浸渍提拉法在玻璃表面制备了锐钛矿型多孔TiO2薄膜.随着前驱物中聚乙二醇加入量及分子量的增加,聚乙二醇热分解后在薄膜中产生气孔的数量增多,孔径增大,TiO2薄膜表面的羟基含量也增加.TiO2薄膜中引入适当大小的微孔可明显提高薄膜的光催化活性;当孔径接近400nm时,光的散射增强,透光率下降,薄膜的光催化活性降低. 相似文献
592.
Nguyen Vu Ngoc Mai Duong Thi Lim Nguyen Quang Bac Nguyen Thi Ha Chi Doan Trung Dung Ngo Nghia Pham Dao Ngoc Nhiem 《中国化学会会志》2020,67(2):242-245
In this study, nanoparticles of Fe2O3/Mn2O3 mixture were obtained using the sol–gel method. The synthesis uses the combination of polyvinyl alcohol (PVA) and tartaric acid (TA). Synthesized catalysts prove superior compared to those afforded from previous reports. To be specific, desired catalysts can be received at lower calcination temperature. Furthermore, their structures display higher uniformity in term of particle sizes. Finally, they show better performance for the photocatalytic degradation of model-persistent organic compounds. 相似文献
593.
不锈钢基底上TiO2薄膜型光催化剂的制备和化学结构 总被引:23,自引:0,他引:23
采用钛酸正丁酯作为前驱体,通过溶胶-凝胶法在不锈钢基片上制备了TiO2纳米薄膜。利用俄歇电子能谱(AES)和紫外反射光谱等研究手段,对TIO2薄膜的化学结构及基底材料界面相互作用进行了系统研究。结果发现,在不锈钢基底上形成的TiO2薄膜与基底材料发生了明显的界面扩散反应。在TiO2薄膜的形成过程中,不锈钢中Fe元素向TiO2薄膜层扩散,并与从大气氛中扩散到界面的氧发生化学反应,形成铁氧化物界面过渡层。界面氧化过程,导致了Fe向样品表面的偏析和扩散。在高温热处理过程中,Fe可以扩散到TiO2薄膜的表面。薄膜催化剂的紫外反射光谱表明,界面扩散反应导致了Fe扩散进入TiO2薄膜的晶格,从而改变了薄膜催化剂的光吸收性能。 相似文献
594.
Sol‐gel bonded packing materials in continuous‐bed columns have been prepared for capillary electrochromatography (CEC). Three packing materials were investigated: small‐pore Spherisorb ODS1 (3 μm, 80 Å) with octadecyl as stationary phase, small‐pore mixed‐mode Spherisorb ODS/SCX (3 μm, 80 Å) with octadecyl and propyl sulfonic acid as stationary phases, and large‐pore Nucleosil ODS (7 μm, 1 400 Å) with octadecyl as stationary phase. The characteristics of these columns were compared in terms of electroosmotic flow, efficiency, inertness, and retention factors. In contrast to columns containing sol‐gel bonded ODS, columns containing sol‐gel bonded mixed‐mode ODS/SCX generated nearly pH independent electroosmotic flow (EOF) over pH 2–9. Columns containing sol‐gel bonded large‐pore ODS produced nearly three times lower reduced plate height than those containing small‐pore ODS. Efficiencies of 220,000 plates per meter and 175,000 plates per meter were obtained from columns containing sol‐gel bonded 7 μm, 1 400 Å ODS and columns containing sol‐gel bonded 3 μm, 80 Å ODS, respectively, which are among the highest reported efficiencies for continuous‐bed columns. In CEC, over one million plates per meter and pH independent EOF are expected from continuous‐bed columns containing sol‐gel bonded 1.5 μm particles with large pores and mixed‐mode stationary phases. 相似文献
595.
Yoshinori Akamatsu Kensuke Makita Hiroshi Inaba Hiroyuki Nakazumi Tsutomu Minami 《Journal of Sol-Gel Science and Technology》2000,19(1-3):387-391
We have prepared the recyclable colored glass plates of blue, green, or red by coating organic colorant dispersed silica sols. Phthalocyanine-type or diketopyrrolopyrrole-type compounds were used as colorants for colored coating and the sol coated glass plates were heat-treated at 300–400°C. The coating was done by using a dipping-withdrawing equipment designed originally for coating large sized glass plates with 2 m in length and 1 m in width. The colored coating films were uniform and transparent with low haze values less than 1.0% and with thickness of 120–540 nm. The visible light transmittance of the colored glass plates was controlled in the relatively wide range of 50–90% by changing the film thickness or the colorant concentration in the coating sols. The practical durabilities of the blue colored glass plate against abrasion, scratch, chemicals and UV-light were acceptable to the specification required for interior glass products. 相似文献
596.
研究了在不同耐尔蓝A浓度,银溶胶,激发波长和pH值以及碘离子存在下,耐尔蓝A在银溶胶上的表面增强拉曼光谱特征。 相似文献
597.
Au@SiO2核壳结构-表面增强拉曼光谱原位检测食品中的酸性橙Ⅱ 总被引:1,自引:0,他引:1
以具有核壳结构的Au@SiO2纳米颗粒为基底,建立了一种以表面增强拉曼(SERS)原位、快速检测食品中非法添加剂酸性橙Ⅱ的新方法.研究了活性硅加入量对所形成的Au@SiO2纳米颗粒的SERS活性的影响,制备了具有最佳SERS活性的Au@SiO2,并以此为SERS基底建立了酸性橙Ⅱ的分析方法,可实现0.17 mg/L酸性橙Ⅱ的SERS检测.将合成的Au@SiO2滴加到瓜子表面后,可以实现对瓜子表面酸性橙Ⅱ浓度为0.01 mg/g时的SERS检测,能够满足食品中酸性橙Ⅱ的测定要求,有望用于瓜子及其它可能被非法添加该物质的食品的现场、快速检测. 相似文献
598.
599.
Lowell R. Matthews Xiao-Jun Wang E. T. Knobbe 《Journal of Sol-Gel Science and Technology》1994,2(1-3):627-634
The narrow, intense emission bands of europium (III) make its compounds of interest for various optical source applications. Previous studies have indicated that complexes like tris(4,4,4-trifluoro-1-(2-thieny1)-1,3-butanedionato-O,O)europium(III), Eu(ttfa)3, have superior fluorescence properties in select media with respect to comparable inorganic salts like EuCl3. It has been shown that such complexes are readily incorporated into solid-state matrices via the sol-gel process. The present research examines the luminescence behavior of Eu(ttfa)3 and EuCl3 doped into a sol-gel-derived epoxy-diol ORMOSIL host, and extends our earlier work involving doped silica and acrylate ORMOSIL gel materials. The present study focuses on the effects of dopant-matrix interactions and seeks to compare the emission behavior of Eu(ttfa)3 and EuCl3 in silica and epoxy-diol ORMOSIL gel host materials. 相似文献
600.
本文较系统研究了碘离子与对甲基苯磺酸甲酷在CH30H, C2HSOH, n-C,H,OH,CH,COCH,和DMF等溶剂及CH,COCH,-H20混合溶剂中的反应动力学特性.实验测定了反应活化能,指前因子、活化嫡和活化焙.在CH,COCH3-HZO混合溶剂中,E,c\S*和八付钟值随Hz0的摩尔分数增加而降低.实验还测得与溶剂笼子有关的配位数n值,并对溶剂化机理作了探讨. 相似文献