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《中国稀土学报(英文版)》2022,40(6):906-915
Exploring an alternative strategy with high efficiency and low cost to abate formaldehyde (HCHO) in indoor environment, is of increasing significance for people's health. CeO2 catalysts prepared by hydrothermal, precipitation and calcination methods were investigated for HCHO removal at ambient temperature. It is found that indoor fluorescent light visibly boosts the catalytic performance of CeO2 catalysts for HCHO decomposition at ambient temperature. Among the CeO2 catalysts, CeO2 prepared from hydrothermal method (CeO2–H) exhibits a superior catalytic performance and an excellent durability by eight recycle times. Based on the characterization and analysis, the excellent catalytic performance of CeO2–H is mainly contributed by its abundance of surface oxygen vacancies, and photogenerated electrons and hole activated by fluorescent light. This work shows a potential practicability in HCHO pollution elimination by taking full advantage of the existing lighting in indoor environments. 相似文献
13.
SUN Jian LIN Dongliang Shanghai Jiaotong University Shanghai China LIN Dongliang professor Department of Materials Science Shanghai Jiaotong University Shanghai China 《金属学报(英文版)》1993,6(5):332-336
Equilibrium equation of point defects in Ll_2 type intermetallic compounds was established tocalculate the relations of the concentration of antisite defects and vacancies and bulk composi-tion in Ni_3Al.The examination of temperature effects on the point defects cleared up the mis.understanding of the properties of the“constitutional point defects”in Ni_3Al. 相似文献
14.
Carlos R. Vera Carlos L. Pieck Kiyoyuki Shimizu Jos M. Parera 《Applied Catalysis A: General》2002,230(1-2):137-151
An assessment of the influence of the crystal structure, surface hydroxylation state and previous oxidation/reduction pretreatments on the activity of sulfate-zirconia catalysts for isomerization of n-butane was performed using crystalline and amorphous zirconia supports. Different sulfation methods were used for the preparation of bulk and supported SO42−-ZrO2 with monoclinic, tetragonal and tetragonal+monoclinic structures. Activity was important only for the samples that contained tetragonal crystals. The catalysts prepared from pure monoclinic zirconia showed negligible activity. SO42−-ZrO2 catalysts prepared by sulfation of crystalline zirconia displayed sites with lower acidity and cracking activity than those sulfated in the amorphous state. Prereduction of the zirconia samples with H2 was found to greatly increase the catalytic activity, and a maximum rate was found at a reduction temperature of 550–600 °C, coinciding with a TPR peak supposedly associated with the removal of lattice oxygen and the creation of lattice defects. A weaker dependence of catalytic activity on the density or type of surface OH groups on zirconia (before sulfation) was found in this work.
A model of active site generation was constructed in order to stress the dependence on the crystal structure and crystal defects. Current and previous results suggest that tetragonal structure in active SO42−-ZrO2 is a consequence of the stabilization of anionic vacancies in zirconia. Anionic vacancies are in turn supposed to be related to the catalytic activity for n-butane isomerization through the stabilization of electrons from ionized intermediates. 相似文献
15.
Nd2O3掺杂BaTiO3陶瓷的结构和电性能研究 总被引:5,自引:0,他引:5
研究了组份为Ba1-xNdxTiO3(x=0.002-0.04)陶瓷的结构和电性能,实验结果表明:当0.002≤x≤0.004时,轻度Nd2O3掺杂的BaTiO3陶瓷呈半导体;而当0.012≤x≤0.04时呈绝缘性。BaTiO3陶瓷的室温电阻率ρv随Nd^3+含量的变化呈U型特曲线。组份为Ba0.9970Nd0.0030TiO3的材料具有最低的ρv和最佳的PTCR效应,相应于最大的平均晶粒尺寸和最 相似文献
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氧空位对氧化锆相结构稳定性及相变过程的影响 总被引:9,自引:0,他引:9
从晶体学和配位学的角度,结合电化学技术,讨论了氧空位对氧化锆相结构结构稳定性的影响及氧化锆四方相单斜相转变过程中的作用。结果表明:氧空位的存在与变化不仅影响着氧化锆相结构的稳定性,而且影响着氧化锆的低温相变过程。对于含有一定担氧空位的亚稳四方相氧化锆,氧空位浓度的增加与减少都会进一步降低其结构稳定性,使之更加容晚地向单斜相转变 相似文献
18.
WANG Haili JI Huifang SUN Shuxiang DING Peng JIN Zhi WEI Zhichao ZHONG Yinghui LI Yuxiao 《西安电子科技大学学报(自然科学版)》2017,44(4):151
InP-based high electron mobility transistors (HEMT) have shown a great potential for national defense and satellite radar in space radiation environment applications. This paper studies the proton radiation damage mechanism of its critical structure InAlAs/InGaAs/InAlAs quantum well. The proton projection range and vacancy defect information are obtained at different incident proton energies of 50keV, 75keV and 200keV by SRIM software. With the increase of proton energy, the proton injection depth is increasing and eventually protons pass through the material layers. Besides, the proton radiation induced vacancy defects numbers around hetero-junction increase first and decrease subsequently, and As vacancies are the main proton radiation induced defects. In addition, non-ionizing energy loss (NIEL) of In0.52Al0.48As and In0.53Ga0.47As material is computed under different incident proton energies by the analytical model. The change trend of NIEL is identical to the induced vacancy numbers, namely, NIEL first increases and then decreases as the incident proton energy increases. Finally the degrading effect of the radiation-induced As defect is detected in the two-dimensional electron gas in the quantum well, which confirms that the major proton radiation damage mechanism of the quantum well is the induced vacancy defects by NIEL. 相似文献
19.
梁婷 《吉林化工学院学报》2014,31(11):94-97
采用第一性原理赝势平面波方法,通过Materials Studio软件中的Castep模块,建立Al2O3晶胞,稀土元素Y的加入有助于控制Al2O3或Cr2O3的生长速度,减少氧化薄膜和基体间形成空洞,从而提高氧化薄膜的粘附性.稀土元素La的加入与S形成化合物,消除S对基体产生的不良反应,改善了氧化薄膜的粘附性. 相似文献
20.
万芳 《四川烹饪高等专科学校学报》2014,(4):8-12
以读者为中心的接受美学理论已广泛运用在翻译理论的研究和实践上,为翻译理论提供了新的视角和方法。"意义空白"是接受美学的重要思想。"意义空白"一般有两种:一种是语言本身存在的不确定性,是一种无法表达的表达;另一种是作者为了制造再创造的空间而采用的手段。为了实现"意义空白",在翻译中通常采用补充或保留"意义空白"。随着我国国际交流的深入,川菜也开始走出国门,走向世界。但川菜在受到国外友人喜爱的同时,也因为菜名翻译方法的不规范而使川菜的传播受到一定的影响。文章拟从接受美学的角度,探寻"意义空白"理论对川菜菜名日译的指导作用。 相似文献