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本研究使用低温溶胶凝胶自燃法制备了不同载体负载的CuMn2O4/MO2(M=Mn、Ti、Ce)催化剂,并对其同时去除甲苯和NOx的性能进行了评价。结果表明,CeO2载体的加入可显著缓解CuMn2O4上甲苯氧化与NH3-SCR的相互抑制,因此,CuMn2O4/CeO2催化剂表现出最优异的甲苯与NOx同时去除效率。通过BET、XRD、NH3-TPD、O2-TPD及结合XPS与in-situ DRIFTs对催化剂的物化性质及CuMn2O4同时去除甲苯与NOx的反应机理进行了分析。结果表明,CeO2的引入提高了催化剂中Mn4+/Mnn+的占比,促使CuMn 相似文献
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利用升温重结晶过程制备硫酸钙晶须,考察了溶液pH值、升温区间、振荡速率等操作条件对晶须生成及形貌的影响,并初步探索了十六烷基三甲基溴化铵(CTAB)、十二烷基硫酸钠(SDS)、聚乙二醇(PEG6000)和乙二胺(EDA)四种表面活性剂对晶须形貌的影响.结果表明:在升温重结晶反应体系中,各操作条件均可对晶须产物的形貌和尺寸产生影响,但pH和升温区间的影响最大;SDS会显著抑制晶核形成,质量浓度为7 g/L时生成的产物形貌为均一棒状,结晶度较高.硫酸钙晶须主要以层状形貌结构生长,少部分晶须呈现类似多晶和外延生长的形貌. 相似文献
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The dipole resonances of gold nanocages were investigated theoretically using finite difference time domain method.The results show that field enhancement is obtained at the walls of the gold nanocages.It is believed that the effect can cause a strong optical nonlinear property.To test the hypothesis,nonlinear absorption was investigated using a broadband 5 ns Z scan.It was found that at low intensities the sample shows saturable absorption(SA),while at higher intensities a switch from SA to reverse SA occurs.Moreover,the nonlinear absorption of the sample is sensitively wavelength-dependent,and,in the resonant region,saturation intensity is the largest. 相似文献
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The determination of the thickness and the optical dispersion property of gold film using spectroscopy of a surface plasmon in the frequency domain 下载免费PDF全文
We propose to use wavelength modulation approach,i.e.,the spectroscopy of a surface plasmon in the frequency domain,to characterize the optical dispersion property of gold film.Using this method,we determine the dispersion relationship of gold film in a wavelength range from 537.12 nm to 905.52 nm,and our results accord well with the reported results by other authors.This method is particularly suited for studying the optical dispersion properties of thin metal films,because a series of dielectric constants over a wide spectral range can be determined simultaneously via only a single scan of the incident angle,thereby avoiding the repeated measurements required when using the angular modulation approach. 相似文献
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Determination of thickness and optical dispersion property of gold film using spectroscopy of surface plasmon in frequency domain 下载免费PDF全文
We propose to use wavelength modulation approach, i.e., the spectroscopy of surface plasmon in frequency domain to characterize the optical dispersion property of gold film. Using this method, we determine the dispersion relationship of gold film in a wavelength range from 537.12 nm to 905.52 nm, and our results accord well with the reported results by other authors. This method is particularly suited for studying the optical dispersion properties of thin metal films, because a series of dielectric constants over a wide spectral range can be determined simultaneously via only a single scan of the incident angle, thereby avoiding the repeated measurements required when using angular modulation approach. 相似文献
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负载型钙钛矿催化氧化NO及抗SO_2性能研究 总被引:1,自引:0,他引:1
采用柠檬酸络合浸渍法制备了负载型钙钛矿氧化物La1-xCexCoO3/CeO2(x=0~0.3)催化剂,考察了不同Ce掺杂量对其催化氧化NO和抗硫性能的影响,并运用X射线衍射(XRD)、傅里叶红外光谱(FT-IR)、氮气物理吸附、程序升温还原(H2-TPR)、氧气程序升温脱附(O2-TPD)等手段对催化剂进行了表征。结果表明,催化剂的活性与其比表面积大小和氧化还原性质密切相关;其中,负载型钙钛矿La0.8Ce0.2CoO3/CeO2催化剂在300℃时催化氧化NO的转化率达78%。在添加CeO2作载体后,不仅改善了非负载性钙钛矿的低温活性,而且抗硫性能也显著提高。 相似文献
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浸渍法制备了催化剂V2O5-Sb2O3-TiO2,考察了V2O5、Sb2O3负载量、pH值和焙烧温度对催化剂V2O5- Sb2O3-TiO2低温氨选择性催化还原(SCR)NO活性的影响;同时,考察了催化剂V2O5-Sb2O3-TiO2抗H2O和SO2毒化性能。结果表明,V2O5和Sb2O3负载量分别为5%和2%、焙烧温度为400℃、pH值为4时,催化剂SCR活性最好,反应温度220℃时,可达97%。Sb2O3的加入不仅能增强V2O5/TiO2的催化活性,而且能明显提高催化剂的抗H2O和SO2毒化性能。SO2、NO吸附暂态反应和TG-DTG测试表明,Sb2O3的促进机制主要是促进了催化剂在SO2存在条件下对NO的吸附,同时,减弱了硫酸铵盐与催化剂之间的相互作用,硫酸铵盐更容易分解。 相似文献