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Rh2O3/hexagonal CePO4 nanocatalysts for N2O decomposition

Huan Liu, Zhen Ma

《化学科学与工程前沿（英文）》 2017年 第11卷 第4期   页码 586-593 doi: 10.1007/s11705-017-1659-6

摘要： Hexagonal CePO nanorods were prepared by a precipitation method and hexagonal CePO nanowires were prepared by hydrothermal synthesis at 150 °C. Rh(NO ) was then used as a precursor for the impregnation of Rh O onto these CePO materials. The Rh O supported on the CePO nanowires was much more active for the catalytic decomposition of N O than the Rh O supported on CePO nanorods. The stability of both catalysts as a function of time on stream was studied and the influence of the co-feed (CO , O , H O or O /H O) on the N O decomposition was also investigated. The samples were characterized by N adsorption-desorption, inductively coupled plasma optical emission spectroscopy, X-ray diffraction, transmission electron microscopy, X-ray photoelectron microscopy, hydrogen temperature-programmed reduction, oxygen temperature-programmed desorption, and CO temperature-programmed desorption in order to correlate the physicochemical and catalytic properties.

关键词： Rh2O3     CePO4     N2O decomposition    

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Investigation of fluorescence characterization and electrochemical behavior on the catalysts of nanosized Pt-Rh

Chang-Mao HUNG, Wen-Liang LAI, Jane-Li LIN

《环境科学与工程前沿（英文）》 2013年 第7卷 第3期   页码 428-434 doi: 10.1007/s11783-013-0517-0

摘要： This work describes the environmentally friendly technology for oxidation of ammonia (NH ) to form nitrogen at temperatures range from 423K to 673K by selective catalytic oxidation (SCO) over a nanosized Pt-Rh/γ-Al O catalyst prepared by the incipient wetness impregnation method of hexachloroplatinic acid (H PtCl ) and rhodium (III) nitrate (Rh(NO ) ) with γ-Al O in a tubular fixed-bed flow quartz reactor (TFBR). The characterization of catalysts were thoroughly measured using transmission electron microscopy (TEM), three-dimensional excitation-emission fluorescent matrix (EEFM) spectroscopy, UV-Vis absorption, dynamic light-scattering (DLS), zeta potential meter, and cyclic voltammetry (CV). The results demonstrated that at a temperature of 673K and an oxygen content of 4%, approximately 99% of the NH was removed by catalytic oxidation over the nanosized Pt-Rh/γ-Al O catalyst. N was the main product in NH -SCO process. Further, it reveals that the oxidation of NH was proceeds by the over-oxidation of NH into NO, which was conversely reacted with the NH to yield N . Therefore, the application of nanosized Pt-Rh/γ-Al O catalyst can significantly enhance the catalytic activity toward NH oxidation. One fluorescent peak for fresh catalyst was different with that of exhausted catalyst. It indicates that EEFM spectroscopy was proven to be an appropriate and effective method to characterize the Pt clusters in intrinsic emission from nanosized Pt-Rh/γ-Al O catalyst. Results obtained from the CV may explain the significant catalytic activity of the catalysts.

关键词： ammonia (NH3)     nanosized Pt-Rh/γ-Al2O3 catalyst     excitation-emission fluorescent matrix (EEFM)     selective catalytic oxidation (SCO)     tubular fixed-bed reactor (TFBR)    

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PM-support interfacial effect and oxygen mobility in Pt, Pd or Rh-loaded (Ce,Zr,La)O catalysts

《环境科学与工程前沿（英文）》 2021年 第15卷 第4期 doi: 10.1007/s11783-020-1369-z

摘要：

• Pt/CZL exhibits the optimum catalytic performance for HC and NOx elimination.

关键词： Precious metal-loaded (Ce     Zr     La)O2 catalysts     Oxygen mobility     Catalytic performance    

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The stabilization effect of Al2O3 on unconventional Pb/SiO2 catalyst

《化学科学与工程前沿（英文）》 2023年 第17卷 第10期   页码 1423-1429 doi: 10.1007/s11705-023-2315-y

摘要： Similar to Sn, Pb located at the same group (IVA) in the periodic table of elements, can also catalyze propane dehydrogenation to propene, while a fast deactivation can be observed. To enhance the stability, the traditional carrier Al2O3 with a small amount, was introduced into Pb/SiO2 catalyst in this study. It has been proved that Al2O3 can inhibit the reduction of PbO, and weaken the agglomeration and loss of Pb species due to its enhanced interaction with Pb species. As a result, 3Al15Pb/SiO2 catalyst exhibits a much higher stability up to more than 150 h. In addition, a simple schematic diagram of the change of surface species on the catalyst surface after Al2O3 addition was also proposed.

关键词： Pb/SiO2     Al2O3     propane dehydrogenation     propene     stability    

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含稀释剂的Al-Cr2O3体系燃烧合成反应热力学分析与反应模型

张衍诚,潘冶,张传

《中国工程科学》 2004年 第6卷 第6期   页码 63-67

摘要：

对含稀释剂Al203和Cr<sub>2</sub>0<sub>3</sub>的Al-Cr<sub>2</sub>0<sub>3</sub>体系燃烧合成反应进行了热力学计算与分析，讨论了起始反应温度T<sub>0</sub>、稀释剂Al<sub>2</sub>O<sub>3</sub>和Cr<sub>2</sub>O<sub>3</sub>的含量对绝热反应温度7^的影响，并得出T<

关键词： 金属陶瓷     燃烧合成     Al-Cr203体系     热力学     反应模型    

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Al2O3-MxOy硬面陶瓷涂层的喷焊制备及性能研究

王飚,王宇栋,李慧玲,张自华

《中国工程科学》 2002年 第4卷 第9期   页码 75-80

摘要：

在碳钢母材上，用氧乙炔焰喷焊镍包铝合金粉末制取预涂层，喷焊50% Al2O3+50% Ni的复合粉末制取过渡层，用等离子喷焊Al2O3 - MxOy复合粉末制取最终涂层。

关键词： Al2O3-MxOy     涂层     等离子     抗腐蚀     抗磨损    

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Accurate quantification of 3′-terminal 2′-O-methylated small RNAs by utilizing oxidative deep sequencing

《医学前沿（英文）》 2022年 第16卷 第2期   页码 240-250 doi: 10.1007/s11684-021-0909-7

摘要： The continuing discoveries of novel classes of RNA modifications in various organisms have raised the need for improving sensitive, convenient, and reliable methods for quantifying RNA modifications. In particular, a subset of small RNAs, including microRNAs (miRNAs) and Piwi-interacting RNAs (piRNAs), are modified at their 3′-terminal nucleotides via 2′-O-methylation. However, quantifying the levels of these small RNAs is difficult because 2′-O-methylation at the RNA 3′-terminus inhibits the activity of polyadenylate polymerase and T4 RNA ligase. These two enzymes are indispensable for RNA labeling or ligation in conventional miRNA quantification assays. In this study, we profiled 3′-terminal 2′-O-methyl plant miRNAs in the livers of rice-fed mice by oxidative deep sequencing and detected increasing amounts of plant miRNAs with prolonged oxidation treatment. We further compared the efficiency of stem-loop and poly(A)-tailed RT-qPCR in quantifying plant miRNAs in animal tissues and identified stem-loop RT-qPCR as the only suitable approach. Likewise, stem-loop RT-qPCR was superior to poly(A)-tailed RT-qPCR in quantifying 3′-terminal 2′-O-methyl piRNAs in human seminal plasma. In summary, this study established a standard procedure for quantifying the levels of 3′-terminal 2′-O-methyl miRNAs in plants and piRNAs. Accurate measurement of the 3′-terminal 2′-O-methylation of small RNAs has profound implications for understanding their pathophysiologic roles in biological systems.

关键词： small RNAs     2′-O-methylation     sequencing     RT-qPCR    

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Effect of TiO 2 loading on the activity of V/TiO 2 -Al 2 O 3 in the catalytic oxidehydrogenation of ethylbenzene

Xiaohong LI, Wenying LI,

《化学科学与工程前沿（英文）》 2010年 第4卷 第2期   页码 142-146 doi: 10.1007/s11705-009-0233-2

摘要： TiO-AlOmixed oxides with different compositions ranging from 40wt-% to 95wt-% of TiO were prepared by sol-gel method and impregnated with different amounts of VO. Supports and catalysts were characterized by X-ray diffraction (XRD), physisorption, temperature preprogrammed reduction (H-TPR), and ammonia temperature programmed desorption (NH-TPD). TiO content in the support had obvious effect on the crystal structure, texture characteristic, acid property, and catalytic activity in dehydrogenation of ethylbenzene (EB) with carbon dioxide. The highest catalytic activity was acquired when the TiO content was 50 wt-%.

关键词： desorption     different     TiO-AlOmixed     physisorption     ethylbenzene    

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Al2O3 and CeO2-promoted MgO sorbents for CO2 capture at moderate

Huimei Yu, Xiaoxing Wang, Zhu Shu, Mamoru Fujii, Chunshan Song

《化学科学与工程前沿（英文）》 2018年 第12卷 第1期   页码 83-93 doi: 10.1007/s11705-017-1691-6

摘要： A series of Al O and CeO modified MgO sorbents was prepared and studied for CO sorption at moderate temperatures. The CO sorption capacity of MgO was enhanced with the addition of either Al O or CeO . Over Al O -MgO sorbents, the best capacity of 24.6 mg-CO /g-sorbent was attained at 100 °C, which was 61% higher than that of MgO (15.3 mg-CO /g-sorbent). The highest capacity of 35.3 mg-CO /g-sorbent was obtained over the CeO -MgO sorbents at the optimal temperature of 200 °C. Combining with the characterization results, we conclude that the promotion effect on CO sorption with the addition of Al O and CeO can be attributed to the increased surface area with reduced MgO crystallite size. Moreover, the addition of CeO increased the basicity of MgO phase, resulting in more increase in the CO capacity than Al O promoter. Both the Al O -MgO and CeO -MgO sorbents exhibited better cyclic stability than MgO over the course of fifteen CO sorption-desorption cycles. Compared to Al O , CeO is more effective for promoting the CO capacity of MgO. To enhance the CO capacity of MgO sorbent, increasing the basicity is more effective than the increase in the surface area.

关键词： CO2 capture     MgO sorbents     Al2O3     CeO2     flue gas    

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Feasibility study of plasma sprayed Al2O3 coatings as diffusion barrier on CFC

Kirsten BOBZIN, Lidong ZHAO, Nils KOPP, Thomas WARDA

《机械工程前沿（英文）》 2012年 第7卷 第4期   页码 371-375 doi: 10.1007/s11465-012-0339-y

摘要：

Carbon fibre reinforced carbon (CFC) materials are increasingly applied as sample carriers in modern furnaces. Only their tendency to react with different metals at high temperatures by C-diffusion is a disadvantage, which can be solved by application of diffusion barriers. Within this study the feasibility of plasma sprayed Al2O3 coatings as diffusion barrier was studied. Al2O3 coatings were prepared by air plasma spraying (APS). The coatings were investigated in terms of their microstructure, bonding to CFC substrates and thermal stability. The results showed that Al2O3 could be well deposited onto CFC substrates. The coatings had a good bonding and thermal shock behavior at 1060°C. At higher temperature of 1270°C, crack network formed within the coating, showing that the plasma sprayed Al2O3 coatings are limited regarding to their application temperatures as diffusion barrier on CFC components.

关键词： diffusion barrier coatings     CFC     plasma spraying     microstructure     Al2O3    

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Ultrasound-assisted co-precipitation synthesis of mesoporous Co3O4–CeO2 composite oxides for highly selective

《化学科学与工程前沿（英文）》 2022年 第16卷 第8期   页码 1211-1223 doi: 10.1007/s11705-022-2145-3

摘要： The one-step highly selective oxidation of cyclohexane into cyclohexanone and cyclohexanol as the essential intermediates of nylon-6 and nylon-66 is considerably challenging. Therefore, an efficient and low-cost catalyst must be urgently developed to improve the efficiency of this process. In this study, a Co3O4–CeO2 composite oxide catalyst was successfully prepared through ultrasound-assisted co-precipitation. This catalyst exhibited a higher selectivity to KA-oil, which was benefited from the synergistic effects between Co3+/Co2+ and Ce4+/Ce3+ redox pairs, than bulk CeO2 and/or Co3O4. Under the optimum reaction conditions, 89.6% selectivity to KA-oil with a cyclohexane conversion of 5.8% was achieved over Co3O4–CeO2. Its catalytic performance remained unchanged after five runs. Using the synergistic effects between the redox pairs of different transition metals, this study provides a feasible strategy to design high-performance catalysts for the selective oxidation of alkanes.

关键词： Co3O4–CeO2 composite oxides     cyclohexanone     cyclohexanol     ultrasonic-assisted co-precipitation     selective oxidation     solvent-free    

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Large-scale synthesis of isolated Mn2O3 nanotube/fiber with ferric nitrate as catalyst

ZHANG Aifei, LIU Jiping, L? Guangshu

《化学科学与工程前沿（英文）》 2007年 第1卷 第1期   页码 55-58 doi: 10.1007/s11705-007-0011-y

摘要： Isolated MnO nanotubes and nanofibers were prepared very easily at a large scale with the liquid-phase catalysis method. The MnO nanotubes had dimensions of 30 50 nm (exterior diameter) and 0.2 1.0 ?m (length), approximately. The O nanofibers had dimensions of 10 30 nm (diameter) and 0.4 2.0 ?m (length), approximately. Nano-O with different microstructures including nanotubes, nanofibers and nanoparticles could be selectively synthesized by controlling the contents and proportions of potassium permanganate and ferric nitrate. Ferric nitrate was an ideal catalyst for the preparation of O nanotube/fiber. When cobalt nitrate or nickel nitrate was used as catalyst, only amorphous nano-O was synthesized. X-ray diffraction (XRD) result shows that the O nanotube has a crystalline structure different from o-O, t-O, h-O and ?-O.

关键词： different     nickel     exterior diameter     nanotube     XRD    

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Effects of MgO promoter on properties of Ni/Al2O3 catalysts for partial oxidation of methane to syngas

QIU Yejun, CHEN Jixiang, ZHANG Jiyan

《化学科学与工程前沿（英文）》 2007年 第1卷 第2期   页码 167-171 doi: 10.1007/s11705-007-0031-7

摘要： The effects of MgO promoter on the physico-chemical properties and catalytic performance of Ni/AlO catalysts for the partial oxidation of methane to syngas were studied by means of BET, XRD, H-TPR, TEM and performance evaluation. It was found that the MgO promoter benefited from the uniformity of nickel species in the catalysts, inhibited the formation of NiAlO spinel and improved the interaction between nickel species and support. These results were related to the formation of NiO MgO solid solution and MgAlO spinel. Moreover, for the catalysts with a proper amount of MgO promoter, the nickel dispersiveness was enhanced, therefore making their catalytic performance in methane partial oxidation improved. However, the excessive MgO promoter exerted a negative effect on the catalytic performance. Meanwhile, the basicity of MgO promoted the reversed water gas shift reaction, which led to an increase in CO selectivity and a decrease in H2 selectivity. The suitable content of MgO promoter in Ni/AlO catalyst was ?7 wt-%.

关键词： excessive     selectivity     decrease     dispersiveness     physico-chemical    

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Highly selective catalytic hydrodeoxygenation of guaiacol to cyclohexane over Pt/TiO

Zhong HE,Xianqin WANG

《化学科学与工程前沿（英文）》 2014年 第8卷 第3期   页码 369-377 doi: 10.1007/s11705-014-1435-9

摘要： Catalysts Pt/TiO and NiMo/Al O are highly active and selective for the hydrodeoxygenation of guaiacol in a fixed bed reactor at 300 °C and 7.1 MPa, leading to the hydrogenation of aromatic ring, followed by demethylation and dehydroxylation to produce cyclohexane. For a complete hydrodeoxygenation of guaiacol, metal sites and acid sites are required. NiMo/Al O and Pt/Al O are more active and selective for cyclohexane formation as compared with Pt/TiO at 285 °C and 4 MPa. However, Pt/TiO is stable while the other two catalysts deactivate due to the nature and amount of coke formation during the reaction.

关键词： Pt/TiO2     NiMo/Al2O3     Pt/Al2O3     bio-oil     hydrodeoxygenation     guaiacol     cyclohexane    

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Optimization of the O/HO process with response surface methodology for pretreatment of mother liquor

《环境科学与工程前沿（英文）》 2021年 第15卷 第4期 doi: 10.1007/s11783-020-1371-5

摘要：

• Real ML-GFW with high salinity and high organics was degraded by O3/H2O2 process.

关键词： High salinity     High organic matters     Gas field wastewater     O3/H2O2     Response surface methodology    

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标题 作者 时间 类型 操作

Rh2O3/hexagonal CePO4 nanocatalysts for N2O decomposition

Huan Liu, Zhen Ma

期刊论文

Investigation of fluorescence characterization and electrochemical behavior on the catalysts of nanosized Pt-Rh

Chang-Mao HUNG, Wen-Liang LAI, Jane-Li LIN

期刊论文

PM-support interfacial effect and oxygen mobility in Pt, Pd or Rh-loaded (Ce,Zr,La)O catalysts

期刊论文

The stabilization effect of Al2O3 on unconventional Pb/SiO2 catalyst

期刊论文

含稀释剂的Al-Cr2O3体系燃烧合成反应热力学分析与反应模型

张衍诚,潘冶,张传

期刊论文

Al2O3-MxOy硬面陶瓷涂层的喷焊制备及性能研究

王飚,王宇栋,李慧玲,张自华

期刊论文

Accurate quantification of 3′-terminal 2′-O-methylated small RNAs by utilizing oxidative deep sequencing

期刊论文

Effect of TiO 2 loading on the activity of V/TiO 2 -Al 2 O 3 in the catalytic oxidehydrogenation of ethylbenzene

Xiaohong LI, Wenying LI,

期刊论文

Al2O3 and CeO2-promoted MgO sorbents for CO2 capture at moderate

Huimei Yu, Xiaoxing Wang, Zhu Shu, Mamoru Fujii, Chunshan Song

期刊论文

Feasibility study of plasma sprayed Al2O3 coatings as diffusion barrier on CFC

Kirsten BOBZIN, Lidong ZHAO, Nils KOPP, Thomas WARDA

期刊论文

Ultrasound-assisted co-precipitation synthesis of mesoporous Co3O4–CeO2 composite oxides for highly selective

期刊论文

Large-scale synthesis of isolated Mn2O3 nanotube/fiber with ferric nitrate as catalyst

ZHANG Aifei, LIU Jiping, L? Guangshu

期刊论文

Effects of MgO promoter on properties of Ni/Al2O3 catalysts for partial oxidation of methane to syngas

QIU Yejun, CHEN Jixiang, ZHANG Jiyan

期刊论文

Highly selective catalytic hydrodeoxygenation of guaiacol to cyclohexane over Pt/TiO

Zhong HE,Xianqin WANG

期刊论文

Optimization of the O/HO process with response surface methodology for pretreatment of mother liquor

期刊论文