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On the monolayer dispersion behavior of Co3O4 on HZSM-5 support: designing applicable

《化学科学与工程前沿（英文）》 2023年 第17卷 第11期   页码 1741-1754 doi: 10.1007/s11705-023-2332-x

摘要： Based on monolayer dispersion theory, Co3O4/ZSM-5 catalysts with different loadings have been prepared for selective catalytic reduction of nitrogen oxides by ammonia. Co3O4 can spontaneously disperse on HZSM-5 support with a monolayer dispersion threshold of 0.061 mmol 100 m–2, equaling to a weight percentage around 4.5%. It has been revealed that the quantities of surface active oxygen (O2–) and acid sites are crucial for the reaction, which can adsorb and activate NOx and NH3 reactants effectively. Below the monolayer dispersion threshold, Co3O4 is finely dispersed as sub-monolayers or monolayers and in an amorphous state, which is favorable to generate the two kinds of active sites, hence promoting the performance of ammonia selective catalytic reduction of nitrogen oxide. However, the formation of crystalline Co3O4 above the capacity is harmful to the reaction performance. 4% Co3O4/ZSM-5, the catalyst close to the monolayer dispersion capacity, possesses the most abundant active O2– species and acidic sites, thereby demonstrating the best reaction performance in all the samples. It is proposed the optimal Co3O4/ZSM-5 catalyst can be prepared by loading the capacity amount of Co3O4 onto HZSM-5 support.

关键词： Co3O4/ZSM-5     NOx-SCR by NH3     monolayer dispersion threshold effect     surface acid sites     surface active O2– anions    

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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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Wide gap active brazing of ceramic-to-metal-joints for high temperature applications

K. Bobzin,L. Zhao,N. Kopp,S. Samadian Anavar

《机械工程前沿（英文）》 2014年 第9卷 第1期   页码 71-74 doi: 10.1007/s11465-014-0291-0

摘要：

Applications like solid oxide fuel cells and sensors increasingly demand the possibility to braze ceramics to metals with a good resistance to high temperatures and oxidative atmospheres. Commonly used silver based active filler metals cannot fulfill these requirements, if application temperatures higher than 600°C occur. Au and Pd based active fillers are too expensive for many fields of use. As one possible solution nickel based active fillers were developed. Due to the high brazing temperatures and the low ductility of nickel based filler metals, the modification of standard nickel based filler metals were necessary to meet the requirements of above mentioned applications. To reduce thermally induced stresses wide brazing gaps and the addition of Al2O3 and WC particles to the filler metal were applied. In this study, the microstructure of the brazed joints and the thermo-chemical reactions between filler metal, active elements and WC particles were analyzed to understand the mechanism of the so called wide gap active brazing process. With regard to the behavior in typical application oxidation and thermal cycle tests were conducted as well as tensile tests.

关键词： wide gap     active brazing     nickel filler metals     high temperature application     WC     Al2O3    

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Effect of different acid anions on highly efficient Ce-based catalysts for selective catalytic reduction

《化学科学与工程前沿（英文）》 2023年 第17卷 第10期   页码 1399-1411 doi: 10.1007/s11705-023-2345-5

摘要： Three kinds of Ce-based catalysts (CePO4, CeVO4, Ce2(SO4)3) were synthesized and used for the selective catalytic reduction (SCR) of NO by NH3. NH3-SCR performances were conducted in the temperature range of 80 to 400 °C. The catalytic efficiencies of the three catalysts are as follow: CePO4 > CeVO4 > Ce2(SO4)3, which is in agreement with their abilities of NH3 adsorption capacities. The highest NO conversion rate of CePO4 could reach about 95%, and the catalyst had more than 90% NO conversion rate between 260 and 320 °C. The effect of PO43–, VO43– and SO42– on NH3-SCR performances of Ce-based catalysts was systematically investigated by the X-ray photoelectron spectroscopy analysis, NH3 temperature programmed desorption, H2 temperature programmed reduction and field emission scanning electron microscopy tests. The key factors that can enhance the SCR are the existence of Ce4+, large NH3 adsorption capacity, high and early H2 consumptions, and suitable microstructures for gas adsorption. Finally, CePO4 and CeVO4 catalysts also exhibited relatively strong tolerance of SO2, and the upward trend about 8% was detected due to the sulfation enhancement by SO2 for Ce2(SO4)3.

关键词： CePO4     CeVO4     Ce2(SO4)3     selective catalytic reduction     NO removal    

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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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Tuning of the active phase structure and hydrofining performance of alumina-supported tri-metallic WMoNi

Shufeng Shan, Haiyan Liu, Gang Shi, Xiaojun Bao

《化学科学与工程前沿（英文）》 2018年 第12卷 第1期   页码 59-69 doi: 10.1007/s11705-017-1686-3

摘要： The effects of phosphorus on the structure and hydrofining performance of tri-metallic WMoNi/Al O catalysts prepared with W/Mo-based hybrid precursor nanocrystals were investigated. The incorporation of phosphorus weakened the metal-support interactions (MSIs) and facilitated the formation of more synergetic NiWMoS phases with higher stacks. Catalytic tests using a fluid catalytic cracking diesel fuel showed that the changes in the MSIs and the morphology of the active phases had a more positive effect on the hydrodenitrogenation activity than on the hydrodesulfurization activity. In contrast, when phosphorus was incorporated into a tri-metallic WMoNiP/Al O catalyst prepared by a conventional incipient impregnation method, the MSIs decreased causing aggregation of the metal species which resulted in poorer hydrofining performance of the catalyst. These results show that incorporating phosphorus into a WMoNi/Al O catalyst can finely tune the structure of the active phase to enhance the hydrogenation and hydrodenitrogenation activity of the resulting tri-metallic catalyst.

关键词： fluid catalytic cracking diesel     hydrofining performance     WMoNiP/Al2O3     synergetic effect and structure of NiWMoS phases    

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A low power consumption control scheme: application to a piezostack-based active mount

LOUKIL, O. BAREILLE, M. N. ICHCHOU, M. HADDAR

《机械工程前沿（英文）》 2013年 第8卷 第4期   页码 383-389 doi: 10.1007/s11465-013-0274-6

摘要：

Piezostack-based active mounts have shown great efficiency for vibration control in a wide frequency range. In this paper, we investigate the performances of the global semi-active control strategy presented by Ichchou et al. [ ] for a control system consisting of an active mount and a supported mass. The control strategy allows extracting vibrations energy of the supported mass, storing it in accumulators to be reused for powering in part the actuators (two piezostacks). Consequently, energy needs are reduced versus good control performances comparable to those of the active control based on the negative velocity feedback. The performances of the controller are evaluated in both frequency (transmitted force) and time (acceleration) domains which show that vibrations of the supported mass due to base excitations are efficiently attenuated with the proposed law. An energetic analysis confirms the reduced energy requirement compared to the active scheme.

关键词： hybrid mount     energy     control     piezoelectric     harvesting    

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Centrifuge experiments for shallow tunnels at active reverse fault intersection

Mehdi SABAGH, Abbas GHALANDARZADEH

《结构与土木工程前沿（英文）》 2020年 第14卷 第3期   页码 731-745 doi: 10.1007/s11709-020-0614-7

摘要： Tunnels extend in large stretches with continuous lengths of up to hundreds of kilometers which are vulnerable to faulting in earthquake-prone areas. Assessing the interaction of soil and tunnel at an intersection with an active fault during an earthquake can be a beneficial guideline for tunnel design engineers. Here, a series of 4 centrifuge tests are planned and tested on continuous tunnels. Dip-slip surface faulting in reverse mechanism of 60-degree is modeled by a fault simulator box in a quasi-static manner. Failure mechanism, progression and locations of damages to the tunnels are assessed through a gradual increase in Permanent Ground Displacement (PGD). The ground surface deformations and strains, fault surface trace, fault scarp and the sinkhole caused by fault movement are observed here. These ground surface deformations are major threats to stability, safety and serviceability of the structures. According to the observations, the modeled tunnels are vulnerable to reverse fault rupture and but the functionality loss is not abrupt, and the tunnel will be able to tolerate some fault displacements. By monitoring the progress of damage states by increasing PGD, the fragility curves corresponding to each damage state were plotted and interpreted in related figures.

关键词： reverse fault rupture     continuous tunnel     geotechnical centrifuge     ground surface deformations     fragility curves    

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主动源在高频被动源面波测量中的应用 Article

程逢,夏江海,沈超,胡悦,徐宗博,宓彬彬

《工程（英文）》 2018年 第4卷 第5期   页码 685-693 doi: 10.1016/j.eng.2018.08.003

摘要： 我们称其为“混合源面波”（mixed-source surface-wave，MSW）测量。在记录的时间序列中分别应用了空间自相关（spatial autocorrelation，SPAC）法与基于互相关的被动源面波多道分析方法（multichannel analysis of passive surface

关键词： 被动源面波     主动源面波     高频     混合源面波     空间自相关     被动源面波多道分析    

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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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纺织用表面活性剂的发展及其在节能、减排、节水、降耗中的作用

姚穆

《中国工程科学》 2009年 第11卷 第4期   页码 14-16

摘要：

为适应节能、减排、节水、降耗的要求，近年来纺织用表面活性剂有了较大创新发展。介绍了表面活性剂的主要用途与类别，并就其在染色、印花、脱胶、浆料中的应用进行了举例分析。

关键词： 纺织工业     表面活性剂     节能     节水    

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固体氧化物电解池共电解H2O/CO2研究进展

范慧,宋世栋,韩敏芳

《中国工程科学》 2013年 第15卷 第2期   页码 107-112

摘要： 本文介绍了固体氧化物电解池的结构特点及其用于H2O/CO2的共电解制备H2和CO的工作原理，综述了固体氧化物电解池的组成形式，以及单片电解池和电解池堆用于H2O/CO2共电解反应的国内外研究进展，并阐述了提高固体氧化物电解池共电解效率所亟需解决的问题

关键词： 固体氧化物电解池     H2O/CO2共电解     合成气     电解效率     水电解    

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Construction of nitrogen-doped carbon cladding LiMnO film electrode with enhanced stability for electrochemically selective extraction of lithium ions

《化学科学与工程前沿（英文）》 2023年 第17卷 第12期   页码 2050-2060 doi: 10.1007/s11705-023-2343-7

摘要： Reducing the dissolution of Mn from LiMn2O4 (LMO) and enhancing the stability of film electrodes are critical and challenging for Li+ ions selective extraction via electrochemically switched ion exchange technology. In this work, we prepared a nitrogen-doped carbon cladding LMO (C-N@LMO) by polymerization of polypyrrole and high-temperature annealing in the N2 gas to achieve the above purpose. The modified C-N@LMO film electrode exhibited lower Mn dissolution and better cyclic stability than the LMO film electrode. The dissolution ratio of Mn from the C-N@LMO film electrode decreased by 42% compared to the LMO film electrode after 10 cycles. The cladding layer not only acted as a protective layer but also functioned as a conductive shell, accelerating the migration rate of Li+ ions. The intercalation equilibrium time of the C-N@LMO film electrode reached within an hour during the extraction of Li+ ions, which was 33% less compared to the pure LMO film electrode. Meanwhile, the C-N@LMO film electrode retained evident selectivity toward Li+ ions, and the separation factor was 118.38 for Li+ toward Mg2+ in simulated brine. Therefore, the C-N@LMO film electrode would be a promising candidate for the recovery of Li+ ions from salt lakes.

关键词： LiMn2O4     lithium extraction     surface coating     cyclic stability     Mn dissolution    

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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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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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标题 作者 时间 类型 操作

On the monolayer dispersion behavior of Co3O4 on HZSM-5 support: designing applicable

期刊论文

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

期刊论文

Wide gap active brazing of ceramic-to-metal-joints for high temperature applications

K. Bobzin,L. Zhao,N. Kopp,S. Samadian Anavar

期刊论文

Effect of different acid anions on highly efficient Ce-based catalysts for selective catalytic reduction

期刊论文

Rh2O3/hexagonal CePO4 nanocatalysts for N2O decomposition

Huan Liu, Zhen Ma

期刊论文

Tuning of the active phase structure and hydrofining performance of alumina-supported tri-metallic WMoNi

Shufeng Shan, Haiyan Liu, Gang Shi, Xiaojun Bao

期刊论文

A low power consumption control scheme: application to a piezostack-based active mount

LOUKIL, O. BAREILLE, M. N. ICHCHOU, M. HADDAR

期刊论文

Centrifuge experiments for shallow tunnels at active reverse fault intersection

Mehdi SABAGH, Abbas GHALANDARZADEH

期刊论文

主动源在高频被动源面波测量中的应用

程逢,夏江海,沈超,胡悦,徐宗博,宓彬彬

期刊论文

The stabilization effect of Al2O3 on unconventional Pb/SiO2 catalyst

期刊论文

纺织用表面活性剂的发展及其在节能、减排、节水、降耗中的作用

姚穆

期刊论文

固体氧化物电解池共电解H2O/CO2研究进展

范慧,宋世栋,韩敏芳

期刊论文

Construction of nitrogen-doped carbon cladding LiMnO film electrode with enhanced stability for electrochemically selective extraction of lithium ions

期刊论文

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

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