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51.
Copper iron composite oxides (CuO/Fe2O3) and copper cobalt composite oxides (CuO/Co3O4) for the catalytic reduction of NO with CO at low temperature were prepared by co-precipitation. The catalytic activity and thermal stability of the catalysts were evaluated by a microreactor-GC system. The 100% conversion temperatures of NO are 80 oC for CuO/Fe2O3 and 90 oC for CuO/Co3O4. The catalysts possess high catalytic activity and favorable thermal stability for NO reduction with CO in a wide temperature range and long time range. A systematic study of the molar ratios of the reactants, the volume of NaOH, aging time, and calcination temperature/time was carried out to investigate the influence preparation conditions on the catalytic activity of the catalysts. 相似文献
52.
Wenjuan Yang Yating Zhu Junjun Li Zheng Chen Farhat Nosheen Qitao Zhang Zhicheng Zhang 《中国化学快报》2021,32(1):286-290
The conversion of chemical feedstock materials into high value-added products accompanied with dehydrogenation is of great value in the chemical industry.However,the catalytic dehydrogenation reaction is inhibited by a limited number of expensive noble metal catalysts and lacks understanding of dehydrogenation mechanism.Here,we report the use of heterogeneous non-noble metal iron nanoparticles(NPs) incorporated mesoporous nitrogen-doped carbon to investigate the dehydrogenation mechanism based on experiment observation and density functional theory(DFT) method.Fe NPs catalyst displays excellent performance in the dehydrogenation of 1,2,3,4-tetrahydroquinoline(THQ)with 100% selectivity and 100% conversion for 10-12 h at room temperature.The calculated adsorption energy implies that THQ prefers to adsorb on Fe NPs as compared with absence of Fe NPs.What is more,the energy barrier of transition state is relatively low,illustrating the dehydrogenation is feasible.This work provides an atomic scale mechanism guidance for the catalytic dehydrogenation reaction and points out the direction for the design of new catalysts. 相似文献
53.
Fe(Ш)-doped graphitic carbon nitride (Fe(Ш)-CN) photocatalysts with various Fe(Ш) ions content were prepared via ultrasonic method. Detailed physical characterization indicated that Fe(Ш) ions had been successfully doped into the frame of g-C3N4. The photocatalytic activities were investigated, and methyl orange (MO) and tetracycline hydrochloride (TC) were used as the targeted pollutants. The as-prepared Fe(Ш)-CN materials exhibited higher photocatalytic activities than those of the pure g-C3N4. Specifically, the degradation rate of 2Fe(Ш)-CN under visible light was 2.06 times higher for MO and 2.65 times higher for TC than that of g-C3N4. The increased photocatalytic activities of Fe(Ш)-CN were mainly attributed to the enhanced light absorption ability and the rapid separation of photogenerated carriers. Moreover, the importance of active species during the reaction process was also explored, and the results indicated that •O2− is the main active species. 相似文献
54.
Elizabeth Rojas-García Diana Carolina García-Martínez Ricardo Lpez-Medina Fernando Rubio-Marcos Aldo A. Castaeda-Ramírez Ana M. Maubert-Franco 《Molecules (Basel, Switzerland)》2022,27(20)
Composite materials based on titania nanoparticles (TiO2 NPs) and three metal-organic frameworks (MOFs) called MIL-53 (Fe) ((Fe (III) (OH) (1,4-BDC)), MILs (Materials Institute Lavoisier)), MIL-100 (Fe) (Fe3O(H2O)2OH(BTC)2), and Fe-BTC (iron-benzenetricarboxylate) with different percentages of TiO2 NPs (0.5, 1, and 2.5% wt.) were synthesized using the solvothermal method and used as photocatalytic materials in the degradation of two dyes (Orange II and Reactive Black 5 (RB5)). The pristine and composite materials were characterized with X-ray diffraction, Raman, UV–Vis and Fourier transform infrared spectroscopy and scanning electron microscopy techniques. The 2.5TiO2/MIL-100 composite material showed the best results for the degradation of both dyes (Reactive Black 5 and Orange II dye, 99% and 99.5% degradation in 105 and 150 min, respectively). The incorporation of TiO2 NPs into MOFs can decrease the recombination of the change carrier in the MOF, increasing the photocatalytic activity of a pristine MOF. Results therefore indicated that the synthesized MOF nanocomposites have good potential for wastewater treatment. 相似文献
55.
Rui Li Xin Gou Xinyan Li Hainuo Wang Haibo Ruan Yuting Xiong Xianlun Tang Yuanyuan Li Ping-an Yang 《Molecules (Basel, Switzerland)》2022,27(15)
Flexible strain sensors, when considering high sensitivity and a large strain range, have become a key requirement for current robotic applications. However, it is still a thorny issue to take both factors into consideration at the same time. Here, we report a sandwich-structured strain sensor based on Fe nanowires (Fe NWs) that has a high GF (37–53) while taking into account a large strain range (15–57.5%), low hysteresis (2.45%), stability, and low cost with an areal density of Fe NWs of 4.4 mg/cm2. Additionally, the relationship between the contact point of the conductive network, the output resistance, and the areal density of the sensing unit is analyzed. Microscopically, the contact points of the conductive network directly affect the sensor output resistance distribution, thereby affecting the gauge factor (GF) of the sensor. Macroscopically, the areal density and the output resistivity of the strain sensor have the opposite percolation theory, which affects its linearity performance. At the same time, there is a positive correlation between the areal density and the contact point: when the stretching amount is constant, it theoretically shows that the areal density affects the GF. When the areal density reaches this percolation threshold range, the sensing performance is the best. This will lay the foundation for rapid applications in wearable robots. 相似文献
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卓琳 《广东微量元素科学》2008,15(3):51-54
采用火焰原子吸收光谱法和表面增敏的方法测定了红花中Cu、Fe、Zn的含量。实验表明,使用表面活性剂十二烷基硫酸钠(SDS),可使Zn的吸光度增感34.91%,使Cu增感37.39%,Fe增感232.10%。该法的检测限分别为Zn1.85×10-3μg/mL;Fe1.50×10-2μg/mL;Cu3.50×10-2μg/mL,加标回收率在99.37%~104.23%之间。该法灵敏度高,结果准确,可用于红花等中草药中Cu、Fe、Zn的同时测定。 相似文献
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含蒽酰亚胺基团的化合物N-(2-(6-氨基吡啶))-9-蒽酰亚胺(L1)对Fe3+表现出灵敏的荧光增强响应.L1的衍生物N,N-’(2,6-吡啶基)-二(9-蒽酰亚胺)(L2)对Hg2+在紫外-可见吸收光谱和荧光光谱上显示了良好的识别性.即使在其它金属阳离子存在下,L1和L2分别对于Fe3+和Hg2+仍然表现出较好的选择性. 相似文献