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期刊论文 9

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氧化锆量子点；电阻开关；存储器件；旋涂法 1

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Selective conversion of cellulose to hexitols over bi-functional Ru-supported sulfated zirconia and silica-zirconia

Zhiqiang Song,Hua Wang,Yufei Niu,Xiao Liu,Jinyu Han

《化学科学与工程前沿（英文）》 2015年 第9卷 第4期   页码 461-466 doi: 10.1007/s11705-015-1543-1

摘要： We report a process of selective conversion of microcrystalline cellulose to hexitols over bi-functional Ru-supported sulfated zirconia and silica-zirconia catalysts. A 58.1% yield of hexitols and a 71.0% conversion of cellulose were achieved over Ru/SZSi(100:15)-773 catalyst at 443 K. The as-synthesized catalysts were characterized by X-ray diffraction (XRD), BET, thermogravimetric analysis and pyridine adsorption Fourier transform infrared spectroscopy (FTIR). XRD results indicated that the sulfated catalysts were pure tetragonal phase of ZrO when calcined at 773 K. Monoclinic zirconia appeared at the calcination temperature of 873 K, and the content of monoclinic phase increased with the elevating temperature. Compared with sulfated zirconia catalyst, sulfated silica-zirconia catalysts possessed a higher ratio of Brønsted to Lewis on the surface of catalysts, as shown from pyridine adsorption FTIR results. The reaction results indicated that the tetragonal zirconia, which is necessary for the formation of superacidity, was the active phase to cellulose conversion. The higher amounts of Brønsted acid sites can remarkably accelerate the cellulose depolymerization and promote side reactions that convert C5–C6 alcohols into the unknown soluble degradation products.

关键词： hexitols     cellulose     hydrogenation     sulfated zirconia     ruthenium    

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Effect of alumina and zirconia as binders on the activity of Fe-BEA for NH

Jin Shi, Zihao Zhang, Mingxia Chen, Zhixiang Zhang, Wenfeng Shangguan, Shunchao Gu, Hirano Shin-ichi

《环境科学与工程前沿（英文）》 2018年 第12卷 第1期 doi: 10.1007/s11783-018-1012-4

摘要： Fe-BEA catalysts are active for the NH -SCR of NO. For industrial application, a binder should be added to the Fe-BEA catalysts to make them tightly adhere to the monoliths. The addition of alumina and zirconia as binders to the Fe-BEA led to a different effect on NO conversion. The catalytic activity of the mixed samples was evaluated by the temperature programmed procedure in a flow-reactor system, and the mechanism was analyzed via SEM, BET, XRD and XPS. It was found that larger iron particles were formed by the migration of parent iron particles in the Fe-BEA catalyst with alumina. This led to the increase of Fe magnitude and iron cluster, enhancing the abilities of NO oxidation and storage. Accordingly, the SCR activity increased slightly in low temperature but decreased sharply in high temperature. For the Fe-BEA with zirconia sample, NO oxidation and storage abilities decreased due to the less iron clusters. The increase of Fe magnitude resulted in higher catalytic oxidation ability, which gave rise to little change in the SCR activity compared with the Fe-BEA.

关键词： NH3-SCR     NO     Fe-BEA     Binder     Alumina     Zirconia    

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total oxidizable carbon, phosphate and various metallic ions from HO solution with amino-functionalized zirconia

《化学科学与工程前沿（英文）》 2023年 第17卷 第4期   页码 470-482 doi: 10.1007/s11705-022-2231-6

摘要： Amino-functionalized zirconia was synthesized by the co-condensation method using zirconium butanol and 3-aminopropyltriethoxy silane for the simultaneous removal of various impurities from aqueous 30% H2O2 solution. The results of Fourier transform infrared (FTIR) and Zeta potential showed that the content of N in amino-functionalized zirconia increased with the added amount of 3-aminopropyltriethoxy silane. Accordingly, the removal efficiency of total oxidizable carbon, phosphate and metallic ions from the H2O2 solution increased. The adsorbent with an N content of 1.62% exhibited superior adsorption performance. The removal efficiency of 82.7% for total oxidizable carbon, 34.2% for phosphate, 87.1% for Fe3+, 83.2% for Al3+, 55.1% for Ca2+ and 66.6% for Mg2+, with a total adsorption capacity of 119.6 mg·g–1, could be achieved. The studies conducted using simulated solutions showed that the adsorption process of phosphate on amino-functionalized zirconia is endothermic and spontaneous, and the behaviors could be well described by the pseudo-second-order model and Langmuir model with a maximum adsorption capacity of 186.7 mg·g–1. The characterizations of the spent adsorbents by Zeta potential, FTIR and X-ray photoelectron spectroscopy revealed that the adsorption mechanism of phosphate is predominantly electrostatic attraction by the protonated functional groups and complementary ligand exchange with zirconium hydroxyl groups.

关键词： adsorption     zirconia     total oxidizable carbon     phosphate     metallic ions     hydrogen peroxide    

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Preparation of ceria-zirconia solid solution with enhanced oxygen storage capacity and redox performance

Lijing MENG, Licheng LIU, Xuehong ZI, Hongxing DAI, Hong HE, Zhen ZHAO, Xinping WANG,

《环境科学与工程前沿（英文）》 2010年 第4卷 第2期   页码 164-171 doi: 10.1007/s11783-010-0019-2

摘要： A new method called ultrasonic-assisted membrane reaction (UAMR) was reported for the fabrication of ceria-zirconia solid solution. A series of ceria-zirconia solid solutions with different Ce/Zr molar ratios were prepared by the UAMR method and characterized by X-ray diffraction (XRD), N adsorption, hydrogen temperature-programmed reduction (H-TPR), scanning electron microscope (SEM), and transmission electron microscopy (TEM) techniques. The UAMR method proved to be superior, especially when the Ce/Zr molar ratio was lower than 1, in fabricating ceria-zirconia solid solutions with large BET surface area, high oxygen storage capacity (OSC), and low reduction temperature.

关键词： membrane reaction     ceria-zirconia     Ce/Zr molar ratio     solid solution     hydrogen temperature-programmed reduction (H2-TPR)    

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Polysulfone and zirconia composite separators for alkaline water electrolysis

Li XU, Wei LI, Yan YOU, Shaoxing ZHANG, Yingchun ZHAO

《化学科学与工程前沿（英文）》 2013年 第7卷 第2期   页码 154-161 doi: 10.1007/s11705-013-1331-8

摘要： The novel composite separators composed of polysulfone and zirconia were prepared by phase inversion precipitation technique. This technique allows pre-evaporation time and extraction temperature to be varied in order to obtain optimal performances of the separators. In order to evaluate practical applicability of those composite separators, a small-scale electrolysis experimental apparatus was used to investigate the changes of cell voltage, gas purity and separator stability. The results revealed a decreased cell voltage compared to the conventional asbestos separators, and the gas purity and separator stability met the requirements for industrial use.

关键词： phase inversion     separator     alkaline water electrolysis     mechanical and chemical stability    

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氧化锆量子点用于非易失性电阻式随机存取存储器 Regular Papers

Xiang-lei HE, Rui-jie TANG, Feng YANG, Mayameen S. KADHIM, Jie-xin WANG, Yuan PU, Dan WANG

《信息与电子工程前沿（英文）》 2019年 第20卷 第12期   页码 1698-1705 doi: 10.1631/FITEE.1900363

摘要： 提出一种利用氧化锆量子点作为有源层的非易失性电阻式随机存取器。通过旋涂法制备Ag(上)/ZrO2(有源层)/Ti(下)典型的三明治结构存储器件。该优化器件具有较高高/低电阻差（约10 Ω），良好循环性能（循环数大于100），较低转化电流（约1 μA）。通过原子力显微镜和扫描电子显微镜观察ZrO2有源层表面形貌和堆积状态。实验结果表明，ZrO2有源层紧密堆积，且由于ZrO2量子点分布均匀，ZrO2有源层粗糙度较低（Ra=4.49 nm）。分析了Ag/ZrO2/Ti器件导电机理，并研究银离子导电丝和氧空位对电阻开关记忆行为的影响。该研究为忆阻器材料开发提供了一种简单方案。

关键词： 氧化锆量子点；电阻开关；存储器件；旋涂法    

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Methane partial oxidation over NiO-MgO/Ce

Piyawat PUE-ON, Vissanu MEEYOO, Thirasak RIRKSOMBOOON

《化学科学与工程前沿（英文）》 2013年 第7卷 第3期   页码 289-296 doi: 10.1007/s11705-013-1345-2

摘要： Methane partial oxidation (MPO) is considered as an alternative method to produce hydrogen because it is an exothermic reaction to afford a suitable H /CO ratio of 2. However, carbon deposition on a catalyst is observed as a major cause of catalyst deactivation in MPO. In order to find suitable catalysts that prevent the carbon deposition, NiO-MgO/Ce Zr O (CZO) supported catalysts were prepared via the co-impregnation (C) and sequential incipient wetness impregnation (S) methods. The amount of Ni loading was fixed at 15 wt-% whereas the amount of MgO loading was varied from 5 to 15 wt-%. The results revealed that the addition of MgO shifted the light-off temperatures to higher temperatures. This is because the Ni surface was partially covered with MgO, and the strong interaction between NiO and NiMgO over CZO support led to the difficulty in reducing NiO to active Ni and thus less catalytic activity. However, among the catalysts tested, the 15Ni5Mg/CZO (S) catalyst exhibited the best catalytic stability for MPO after 18 h on stream at 750°C. Moreover, this catalyst had a better resistance to carbon deposition due to its high metallic Ni dispersion at high temperature.

关键词： methane partial oxidation     NiO     ceria-zirconia     MgO     mixed oxide solid solution    

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Brazing of ceramic-to-ceramic and ceramic-to-metal joints in air

Kirsten BOBZIN, Thomas SCHLAEFER, Lidong ZHAO, Nils KOPP, Arne SCHLEGEL

《机械工程前沿（英文）》 2010年 第5卷 第2期   页码 125-129 doi: 10.1007/s11465-010-0007-z

摘要： Reactive air brazing (RAB) is an emerging technology for the production of ceramic-to-ceramic and ceramic-to-metal joints. In this study, RAB was investigated with respect to the potential applications for solid oxide fuel cells (SOFCs) as one example of use. It was found that alumina could be well brazed by RAB with AgCu and AgCuTi brazes. Both braze composition and brazing temperature influenced significantly the wetting behavior and their mechanism of wetting. AgCu and AgCuTi braze alloys could also be used to produce brazed joints with the SOFC materials ceramic yttria stabilized zirconia and steel X1CrTiLa22. However, CuO reacts with the steel, forming a brittle oxide layer on the steel surface, which is undesirable for SOFC applications. The first trials with Ag0.5Al showed a promising solution.

关键词： reactive air brazing (RAB)     X1CrTiLa22     Al2O3     yttria stabilized zirconia (YSZ)     solid oxide fuel cell (SOFC)    

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Preparation and characterization of nanocrystalline ZrO2-7%Y2O3 powders for thermal barrier coatings by high-energy ball milling

Kirsten BOBZIN, Lidong ZHAO, Thomas SCHLAEFER, Thomas WARDA

《机械工程前沿（英文）》 2011年 第6卷 第2期   页码 176-181 doi: 10.1007/s11465-011-0220-4

摘要：

High-energy ball milling is an effective method to produce nanocrystalline oxides. In this study, a conventional ZrO2-7%Y2O3spray powder was ball-milled to produce nanocrystalline powders with high levels of crystalline disorders for deposition of thermal barrier coatings. The powder was milled both with 100Cr6 steel balls and with ZrO2-3%Y2O3 ceramic balls as grinding media. The milling time was varied in order to investigate the effect of the milling time on the crystallite size. The powders were investigated in terms of their crystallite sizes and morphologies by X-ray diffraction analysis (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The results show that under given milling conditions the powder was already nanostructured after 40 min milling. The crystallite size decreased significantly with increasing milling time within first 120 min. After that, a further increase of milling time did not lead to a significant reduction of the crystallite size. Ball-milling led to lattice microstrains. Milling with the steel balls resulted in finer nano-sized crystal grains, but caused the contamination of the powder. The nano-sized crystal grains coarsened during the heat-treatment at 1250°C.

关键词： nanostrucured powders     yttria stabilized zirconia (YSZ)     high-energy ball milling     thermal barrier coatings    

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标题 作者 时间 类型 操作

Selective conversion of cellulose to hexitols over bi-functional Ru-supported sulfated zirconia and silica-zirconia

Zhiqiang Song,Hua Wang,Yufei Niu,Xiao Liu,Jinyu Han

期刊论文

Effect of alumina and zirconia as binders on the activity of Fe-BEA for NH

Jin Shi, Zihao Zhang, Mingxia Chen, Zhixiang Zhang, Wenfeng Shangguan, Shunchao Gu, Hirano Shin-ichi

期刊论文

total oxidizable carbon, phosphate and various metallic ions from HO solution with amino-functionalized zirconia

期刊论文

Preparation of ceria-zirconia solid solution with enhanced oxygen storage capacity and redox performance

Lijing MENG, Licheng LIU, Xuehong ZI, Hongxing DAI, Hong HE, Zhen ZHAO, Xinping WANG,

期刊论文

Polysulfone and zirconia composite separators for alkaline water electrolysis

Li XU, Wei LI, Yan YOU, Shaoxing ZHANG, Yingchun ZHAO

期刊论文

氧化锆量子点用于非易失性电阻式随机存取存储器

Xiang-lei HE, Rui-jie TANG, Feng YANG, Mayameen S. KADHIM, Jie-xin WANG, Yuan PU, Dan WANG

期刊论文

Methane partial oxidation over NiO-MgO/Ce

Piyawat PUE-ON, Vissanu MEEYOO, Thirasak RIRKSOMBOOON

期刊论文

Brazing of ceramic-to-ceramic and ceramic-to-metal joints in air

Kirsten BOBZIN, Thomas SCHLAEFER, Lidong ZHAO, Nils KOPP, Arne SCHLEGEL

期刊论文

Preparation and characterization of nanocrystalline ZrO2-7%Y2O3 powders for thermal barrier coatings by high-energy ball milling

Kirsten BOBZIN, Lidong ZHAO, Thomas SCHLAEFER, Thomas WARDA

期刊论文