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Cell-free biocatalysis coupled with photo-catalysis and electro-catalysis: Efficient CO_(2)-to-chemical conversion
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作者 Junzhu Yang Chi-Kit Sou Yuan Lu 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第9期1366-1383,共18页
The increasing atmospheric carbon dioxide (CO_(2)) concentration has exposed a series of crises in the earth's ecological environment.How to effectively fix and convert carbon dioxide into products with added valu... The increasing atmospheric carbon dioxide (CO_(2)) concentration has exposed a series of crises in the earth's ecological environment.How to effectively fix and convert carbon dioxide into products with added value has attracted the attention of many researchers.Cell-free enzyme catalytic system coupled with electrical and light have been a promising attempt in the field of biological carbon fixation in recent years.In this review,the research progresses of photoenzyme catalysis,electroenzyme catalysis and photo-electroenzyme catalysis for converting carbon dioxide into chemical products in cell-free systems are systematically summarized.We focus on reviewing and comparing various coupling methods and principles of photoenzyme catalysis and electroenzyme catalysis in cell-free systems,especially the materials used in the construction of the coupling system,and analyze and point out the characteristics and possible problems of different coupling methods.Finally,we discuss the major challenges and prospects of coupling physical signals and cell-free enzymatic catalytic systems in the field of CO_(2) fixation,suggesting possible strategies to improve the carbon sequestration capacity of such systems. 展开更多
关键词 CO_(2)fixation Cell-free system Enzyme Photoenzyme catalysis Electroenzyme catalysis
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Non-Gaussian quantum states generated via quantum catalysis and their statistical properties
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作者 张晓燕 杨春燕 +1 位作者 王继锁 孟祥国 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期332-337,共6页
A new kind of non-Gaussian quantum catalyzed state is proposed via multiphoton measurements and two-mode squeezing as an input of thermal state.The characteristics of the generated multiphoton catalysis output state d... A new kind of non-Gaussian quantum catalyzed state is proposed via multiphoton measurements and two-mode squeezing as an input of thermal state.The characteristics of the generated multiphoton catalysis output state depends on the thermal parameter,catalyzed photon number and squeezing parameter.We then analyze the nonclassical properties by examining the photon number distribution,photocount distribution and partial negativity of the Wigner function.Our findings indicate that nonclassicality can be achieved through the implementation of multiphoton catalysis operations and modulated by the thermal parameter,catalyzed photon number and squeezing parameter. 展开更多
关键词 two-mode squeezing multiphoton catalysis NONCLASSICALITY Wigner function
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Identification of origin of insulating polymer maneuvered photoredox catalysis
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作者 Qiao-Ling Mo Rui Xiong +5 位作者 Jun-Hao Dong Bai-Sheng Sa Jing-Ying Zheng Qing Chen Yue Wu Fang-Xing Xiao 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第8期109-123,共15页
Solid non-conjugated polymers have long been regarded as insulators due to deficiency of delocalizedπelectrons along the molecular chain framework.Up to date,origin of insulating polymer regulated charge transfer has... Solid non-conjugated polymers have long been regarded as insulators due to deficiency of delocalizedπelectrons along the molecular chain framework.Up to date,origin of insulating polymer regulated charge transfer has not yet been uncovered.In this work,we unleash the root origin of charge transport capability of insulating polymer in photocatalysis.We ascertain that insulating polymer plays crucial roles in fine tuning of electronic structure of transition metal chalcogenides(TMCs),which mainly include altering surface electron density of TMCs for accelerating charge transport kinetics,triggering the generation of defect over TMCs for prolonging carrier lifetime,and acting as hole-trapping mediator for retarding charge recombination.These synergistic roles contribute to the charge transfer of insulating polymer.Our work opens a new vista of utilizing solid insulating polymers for maneuvering charge transfer toward solar energy conversion. 展开更多
关键词 Insulating polymer Charge transfer Photoredox catalysis POLYELECTROLYTE SELF-ASSEMBLY
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Ordered mesoporous materials for water pollution treatment:Adsorption and catalysis
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作者 Peng Zhang Mingming He +4 位作者 Wei Teng Fukuan Li Xinyuan Qiu Kexun Li Hao Wang 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第8期1239-1256,共18页
To meet the growing emission of water contaminants,the development of new materials that enhance the efficiency of the water treatment system is urgent.Ordered mesoporous materials provide opportunities in environment... To meet the growing emission of water contaminants,the development of new materials that enhance the efficiency of the water treatment system is urgent.Ordered mesoporous materials provide opportunities in environmental processing applications due to their exceptionally high surface areas,large pore sizes,and enough pore volumes.These properties might enhance the performance of materials concerning adsorption/catalysis capability,durability,and stability.In this review,we enumerate the ordered mesoporous materials as adsorbents/catalysts and their modifications in water pollution treatment from the past decade,including heavy metals(Hg^(2+),Pb^(2+),Cd^(2+),Cr^(6+),etc.),toxic anions(nitrate,phosphate,fluoride,etc.),and organic contaminants(organic dyes,antibiotics,etc.).These contributions demonstrate a deep understanding of the synergistic effect between the incorporated framework and homogeneous active centers.Besides,the challenges and perspectives of the future developments of ordered mesoporous materials in wastewater treatment are proposed.This work provides a theoretical basis and complete summary for the application of ordered mesoporous materials in the removal of contaminants from aqueous solutions. 展开更多
关键词 Water pollution treatment Ordered mesoporous materials Toxic contaminants ADSORPTION catalysis
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Structure design and electrochemical properties of carbon-based single atom catalysts in energy catalysis:A review
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作者 Shuqi Li Xincheng Lu +8 位作者 Shuling Liu Jingjing Zhou Yanyan Liu Huanhuan Zhang Ruofan Shen Kang Sun Jianchun Jiang Yongfeng Wang Baojun Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第11期196-236,共41页
Single atom catalysts(SACs) possessing regulated electronic structure, high atom utilization, and superior catalytic efficiency have been studied in almost all fields in recent years. Carbon-based supporting SACs are ... Single atom catalysts(SACs) possessing regulated electronic structure, high atom utilization, and superior catalytic efficiency have been studied in almost all fields in recent years. Carbon-based supporting SACs are becoming popular materials because of their low cost, high electron conductivity, and controllable surface property. At the stage of catalysts preparation, the rational design of active sites is necessary for the substantial improvement of activity of catalysts. To date, the reported design strategies are mainly about synthesis mechanism and synthetic method. The level of understanding of design strategies of carbon-based single atom catalysts is requiring deep to be paved. The design strategies about manufacturing defects and coordination modulation of catalysts are presented. The design strategies are easy to carry out in the process of drawing up preparation routes. The components of carbon-based SACs can be divided into two parts: active site and carbon skeleton. In this review, the manufacture of defects and coordination modulation of two parts are introduced, respectively. The structure features and design strategies from the active sites and carbon skeletons to the overall catalysts are deeply discussed.Then, the structural design of different nano-carbon SACs is introduced systematically. The characterization of active site and carbon skeleton and the detailed mechanism of reaction process are summarized and analyzed. Next, the applications in the field of electrocatalysis for oxygen conversion and hydrogen conversion are illustrated. The relationships between the superior performance and the structure of active sites or carbon skeletons are discussed. Finally, the conclusion of this review and prospects on the abundant space for further promotion in broader fields are depicted. This review highlights the design and preparation thoughts from the parts to the whole. The detailed and systematic discussion will provide useful guidance for design of SACs for readers. 展开更多
关键词 Carbon materials Coordination chemistry Defective structure Energy catalysis Single atom catalysts
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Why the abnormal phenomena of D-band center theory exist?A new BASED theory for surface catalysis and chemistry
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作者 Zelong Qiao Run Jiang +1 位作者 Jimmy Yun Dapeng Cao 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第9期44-53,共10页
Since the D-band center theory was proposed,it has been widely used in the fields of surface chemistry by almost all researchers,due to its easy understanding,convenient operation and relative accuracy.However,with th... Since the D-band center theory was proposed,it has been widely used in the fields of surface chemistry by almost all researchers,due to its easy understanding,convenient operation and relative accuracy.However,with the continuous development of material systems and modification strategies,researchers have gradually found that D-band center theory is usually effective for large metal particle systems,but for small metal particle systems or semiconductors,such as single atom systems,the opposite conclusion to the D-band center theory is often obtained.To solve the issue above,here we propose a bonding and anti-bonding orbitals stable electron intensity difference(BASED)theory for surface chemistry.The newly-proposed BASED theory can not only successfully explain the abnormal phenomena of D-band center theory,but also exhibits a higher accuracy for prediction of adsorption energy and bond length of intermediates on active sites.Importantly,a new phenomenon of the spin transition state in the adsorption process is observed based on the BASED theory,where the active center atom usually yields an unstable high spin transition state to enhance its adsorption capability in the adsorption process of intermediates when their distance is about 2.5Å.In short,the BASED theory can be considered as a general principle to understand catalytic mechanism of intermediates on surfaces. 展开更多
关键词 Surface chemistry Surface catalysis D-band center theory Bonding orbital Anti-bonding orbital
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Pulsed laser interference patterning of transition-metal carbides for stable alkaline water electrolysis kinetics
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作者 Yewon Oh Jayaraman Theerthagiri +3 位作者 Ahreum Min Cheol Joo Moon Yiseul Yu Myong Yong Choi 《Carbon Energy》 SCIE EI CAS CSCD 2024年第5期65-80,共16页
We investigated the role of metal atomization and solvent decomposition into reductive species and carbon clusters in the phase formation of transition-metal carbides(TMCs;namely,Co_(3)C,Fe_(3)C,TiC,and MoC)by pulsed ... We investigated the role of metal atomization and solvent decomposition into reductive species and carbon clusters in the phase formation of transition-metal carbides(TMCs;namely,Co_(3)C,Fe_(3)C,TiC,and MoC)by pulsed laser ablation of Co,Fe,Ti,and Mo metals in acetone.The interaction between carbon s-p-orbitals and metal d-orbitals causes a redistribution of valence structure through charge transfer,leading to the formation of surface defects as observed by X-ray photoelectron spectroscopy.These defects influence the evolved TMCs,making them effective for hydrogen and oxygen evolution reactions(HER and OER)in an alkaline medium.Co_(3)C with more oxygen affinity promoted CoO(OH)intermediates,and the electrochemical surface oxidation to Co_(3)O_(4)was captured via in situ/operando electrochemical Raman probes,increasing the number of active sites for OER activity.MoC with more d-vacancies exhibits strong hydrogen binding,promoting HER kinetics,whereas Fe_(3)C and TiC with more defect states to trap charge carriers may hinder both OER and HER activities.The results show that the assembled membrane-less electrolyzer with Co_(3)C∥Co_(3)C and MoC∥MoC electrodes requires~2.01 and 1.99 V,respectively,to deliver a 10 mA cm−2 with excellent electrochemical and structural stability.In addition,the ascertained pulsed laser synthesis mechanism and unit-cell packing relations will open up sustainable pathways for obtaining highly stable electrocatalysts for electrolyzers. 展开更多
关键词 ACETONE H_(2)and O_(2)evolution reactions pulsed laser ablation surface defects transition-metal carbides water electrolyzer
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Cobalt phthalocyanine promoted copper catalysts toward enhanced electro reduction of CO_(2)to C_(2):Synergistic catalysis or tandem catalysis?
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作者 Yan Luo Jun Yang +6 位作者 Jundi Qin Kanghua Miao Dong Xiang Aidar Kuchkaev Dmitry Yakhvarov Chuansheng Hu Xiongwu Kang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第5期499-507,共9页
The activity and selectivity of electrocatalytic CO_(2)reduction reaction(CO_(2)RR)to C_(2)products on metal catalysts can be regulated by molecular surfactants.However,the mechanism behind it remains elusive and deba... The activity and selectivity of electrocatalytic CO_(2)reduction reaction(CO_(2)RR)to C_(2)products on metal catalysts can be regulated by molecular surfactants.However,the mechanism behind it remains elusive and debatable.Herein,copper nanowires(Cu NWs)were fabricated and decorated with cobalt phthalocyanine(CoPc).The electronic interaction between the Cu NWs,CoPc,CO_(2) and CO_(2)RR intermediates were explored by density functional theory(DFT)calculations.It was found that the selectivity and activity of CO_(2)RR towards C_(2)products on Cu NWs were considerably enhanced from 35.2%to 69.9%by surface decoration of CoPc.DFT calculations revealed that CO_(2)RR can proceed in the interphase between Cu substrate and CoPc,and the CO_(2)RR intermediates could synergistically bond with both Cu and Co metal centre in CuNWs-CoPc,which favours the adsorption of CO_(2),CO and CO_(2)RR intermediates,thus reducing the free energy for CO-COcoupling towards C_(2)products.The synergistic interaction was further extended to phthalocyanine(Pc)and other metal phthalocyanine derivatives(MPc),where a relatively weaker synergistic interaction of COintermediates with MPc and Cu substrate and only a slight enhancement of CO_(2)RR towards C_(2) products were observed.This study demonstrates a synergistic catalysis pathway for CO_(2)RR,a novel perspective in interpreting the role of CoPc in enhancing the activity and selectivity of CO_(2)RR on Cu NWs,in contrast to the conventional tandem catalysis mechanism. 展开更多
关键词 CO_(2)reduction reaction Raman spectroscopy Synergistic catalysis DFT calculation
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Discussion of Misleading on the Interpretation of the Word “Catalysis, Catalyst”
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作者 Jiamin Jin 《Modern Research in Catalysis》 2024年第2期29-37,共9页
The main idea of this paper is what the resource of the serious error of the widely popular Chemical Reaction Mode catalysis Mechanism-CRMM is. The wrong definition of “catalysis, catalyst” by the catalytic academia... The main idea of this paper is what the resource of the serious error of the widely popular Chemical Reaction Mode catalysis Mechanism-CRMM is. The wrong definition of “catalysis, catalyst” by the catalytic academia boss leads to the wrong interpretation of “catalysis, catalyst” by linguists (Dictionary). The interpretation of “catalysis, catalyst” in a dictionary is misleading. The most fundamental reason for this error is that catalysis experts always believe that catalysts participate in chemical reactions. The result will appear as a series of impossible events. Such as catalysis cyclic reaction, opinions vary intermedium, catalysts repeated decomposition—formation, oxidation-reduction or life and death (enzyme), Sabatier’s principle and Boudart’s principle. The wrong theory leads the research and application of catalysts to the bottomless abyss, and industrial production suffers great losses. Electron Orbital Deformation-Recovere cyclic catalysis Mechanism-EODRM or Electron Cyclic Donate-Adopt catalysis Mechanism-ECDAM shows that the catalytic phenomenon is a physical phenomenon, not a chemical phenomenon, the catalyst does not participate in chemical reactions, only contact is the electron donate-adopt cycle, is the electron orbital deformation recovery cycle Chinese and foreign scholars should change the interpretation on the “catalysis, catalyst”, or add two new words: “contact and contactor”, it is to give up “catalysis, catalyst” altogether. 展开更多
关键词 catalysis CATALYST Sabatier Principle Boudart Principle
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Advances in Application of Non-aqueous Phase Enzymatic Catalysis in Food Additive Production 被引量:1
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作者 余泗莲 余琳 +4 位作者 余彬 孙文敬 刘长峰 杨梦依 崔凤杰 《Agricultural Science & Technology》 CAS 2013年第1期169-175,共7页
Non-aqueous phase enzymatic catalysis technology has been widely ap- plied in the area of food additives production. This paper reviewed the types of re- action medium of non-aqueous phase enzymatic catalysis reaction... Non-aqueous phase enzymatic catalysis technology has been widely ap- plied in the area of food additives production. This paper reviewed the types of re- action medium of non-aqueous phase enzymatic catalysis reaction, introduced the application of non-aqueous phase enzymatic catalysis technology in catalysis of L-ascorbic (isoascorbic) acid esters, short-chain acid esters, sugar esters, vitamin A esters, vi- tamin E esters, and other food additives, and finally predicted the prospects of non- aqueous phase enzymatic catalysis technology. 展开更多
关键词 Non-aqueous phase Enzymatic catalysis Food additives Ester synthesis
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基于Catalysis的面向构件建模方法研究
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作者 陈英 王祥宗 《计算机与现代化》 2006年第8期38-41,共4页
介绍了基于Catalysis应用面向构件建模方法进行系统分析、设计、建立系统模型的简洁方法。通过对集团型全面预算管理系统的建模过程,给出了该方法的应用细节,将基于构件的软件开发和企业级应用的特点结合起来,给基于分层结构的企业级软... 介绍了基于Catalysis应用面向构件建模方法进行系统分析、设计、建立系统模型的简洁方法。通过对集团型全面预算管理系统的建模过程,给出了该方法的应用细节,将基于构件的软件开发和企业级应用的特点结合起来,给基于分层结构的企业级软件系统的开发以明确的指导。 展开更多
关键词 catalysis 面向构件技术 建模方法
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Nitrogen ligands in two-dimensional covalent organic frameworks for metal catalysis 被引量:4
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作者 张健强 彭永胜 +3 位作者 冷文光 高艳安 徐斐斐 柴金岭 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第4期468-475,共8页
We introduced bipyridine ligands into a series of two‐dimensional (2D) covalent organic frame‐works (COFs) using 2,2’‐bipyridine‐5,5’‐dicarbaldehyde (2,2’‐BPyDCA) as a component in the mixed building bl... We introduced bipyridine ligands into a series of two‐dimensional (2D) covalent organic frame‐works (COFs) using 2,2’‐bipyridine‐5,5’‐dicarbaldehyde (2,2’‐BPyDCA) as a component in the mixed building blocks. The framework of the COFs was formed by the linkage of imine groups. The ligand content in the COFs was synthetically tuned by the content of 2,2’‐BPyDCA, and thus the amount of metal, palladium(II) acetate, bonded to the nitrogen ligands could be manipulated. Both the bipyri‐dine ligands and imine groups can coordinate with Pd(II) ions, but the loading position can be var‐ied, with one ligand favoring binding in the space between adjacent COFs’ layers and the other lig‐and favoring binding within the pores of the COFs. The Pd(II)‐loaded COFs exhibited good catalytic activity for the Heck reaction. 展开更多
关键词 Covalent organic framework Metal catalysis Heck reaction Nitrogen ligand PALLADIUM
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Chlorobenzene degradation by electro-heterogeneous catalysis in aqueous solution:intermediates and reaction mechanism 被引量:10
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作者 WANG Jiade MEI Yu +1 位作者 LIU Chenliang CHEN Jianmeng 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2008年第11期1306-1311,共6页
This study was performed to investigate the variables that influence chlorobenzene (CB) degradation in aqueous solution by electro-heterogeneous catalysis.The effects of current density,pH,and electrolyte concentratio... This study was performed to investigate the variables that influence chlorobenzene (CB) degradation in aqueous solution by electro-heterogeneous catalysis.The effects of current density,pH,and electrolyte concentration on CB degradation were determined.The degradation effciency of CB was almost 100% with an initial CB concentration of 50 mg/L,current density 15 mA/cm2,initial pH 10,electrolyte concentration 0.1 mol/L,and temperature 25°C after 90 min of reaction.Under the same conditions,the degradation eff... 展开更多
关键词 electro-heterogeneous catalysis ELECTROCHEMICAL CHLOROBENZENE INTERMEDIATES
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Cooperation of nitrogen-doping and catalysis to improve the Li-ion storage performance of lignin-based hard carbon 被引量:5
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作者 Zhewei Yang Huajun Guo +4 位作者 Feifei Li Xinhai Li Zhixing Wang Lizhi Cui Jiexi Wang 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2018年第5期1390-1396,共7页
Hard carbon draws great interests as anode material in lithium ion batteries (LIBs) due to its high the- oretical capacity, high rate capability and abundance of its precursors. Herein we firstly synthesize the lign... Hard carbon draws great interests as anode material in lithium ion batteries (LIBs) due to its high the- oretical capacity, high rate capability and abundance of its precursors. Herein we firstly synthesize the lignin-melamine resins by grafting melamine onto lignin. Afterwards, nitrogen doped hard carbon is pre- pared by the pyrolysis of lignin-melamine resins with the aid of catalyst (Ni(NO_3)2·6H_2O) at 1000 ℃. Compared with the samples without nitrogen-doping and catalysis, as-prepared nitrogen doped hard car- bon exhibits higher reversible capacity (345 mAh g-1 at 0.1 A g-1 ), higher rate capability (145 mAh g-1 at 5 A g-1) and excellent cycling stability. The superior electrochemical performance is ascribed to the synergistic effect of nitrogen doping, graphitic structure and amorphous structure. Among them, nitro- gen doping could create the vacancies around the nitrogen sites, which enhance the reactivity and the electronic conductivity of materials. Additionally, graphitic structure also enhances the electronic con- ductivity of materials, thus improving the electrochemical performance of hard carbon. It is worthwhile that Iignin, renewable and abundant biopolymer, is converted to hard carbon with good electrochemical performance, which realizes the high value utilization of lignin. 展开更多
关键词 Hard carbon LIGNIN MELAMINE NITROGEN-DOPING catalysis
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Catalysis Conversion Methane into C_(2) Hydrocarbons via Electric Field Enhanced Plasma 被引量:5
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作者 Bao Wei WANG Gen Hui XU 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第12期1236-1238,共3页
In this paper the effect of catalyst and carrier in electric field enhanced plasma on methane conversion into C2 hydrocarbons was investigated. Methane coupling reaction was studied in the system of continuous flow r... In this paper the effect of catalyst and carrier in electric field enhanced plasma on methane conversion into C2 hydrocarbons was investigated. Methane coupling reaction was studied in the system of continuous flow reactor on Ni, MoO3, MnO2 catalysts and different ZSM-5 carriers. The per pass conversion of methane can be as high as 22%, the selectivity of ethylene can be as high as 23.8%, of acetylene 60.8%, of ethane 5.4% and of total C2 hydrocarbons was more than 90%. ZSM-5-25 was the better carrier and MnO2 was the better active component. The efficiency of energy was as high as 7.81%. 展开更多
关键词 METHANE electric field enhanced PLASMA catalysis C_(2) hydrocarbons.
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K_2CO_3 catalysis on the reactivity of top charged coke and stamp charged coke 被引量:3
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作者 Qing-hai Pang Jian-liang Zhang +3 位作者 Cheng-lin Qi Chao Ma De-wen Kong Rui Mao 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2013年第1期17-27,共11页
The catalysis of K2CO3 on the reactivity of top charged coke and stamp charged coke from Pansteel in China was studied. The coke reaction index of the stamp charged coke was 1%-2% higher than that of the top charged c... The catalysis of K2CO3 on the reactivity of top charged coke and stamp charged coke from Pansteel in China was studied. The coke reaction index of the stamp charged coke was 1%-2% higher than that of the top charged coke. Under the catalysis of K2CO3, the coke reaction index of both cokes approximately increased by 4%, 6%, 10% and 6% at 900, 1000, 1100 and 1200℃, respectively. The reactivity of the K-enriched stamp charged coke was 1%-2% higher than that of the K-enriched top charged coke below 1100℃. However, only negligible differences were found in the temperature zone between 1100 and 1200℃. Scanning electron microscopy images illustrated that pores in the top charged coke were smaller and equally distributed, while relatively more big pores exist non-homogenously in stamp charged coke. Due to the different processes in production, the stamp charged coke was more porous and most of the pores tended to be applanate. Cracks were observed in the microstructure of the stamp charged coke during the carbon solution reaction, implying the inferior quality of the stamp charged coke to the top charged coke at high temperature. Diffusion of K during the carbon solution reaction was studied by the energy dispersive spectrometry. It is found that K gradually spreads into the center of lumpy coke with the rising of temperature and is equally distributed on the edges of pores at 1200℃. Besides, oxidation reactions of functional groups become faster with the catalysis of K.content 展开更多
关键词 blast furnaces COKE alkali metals catalysis REACTIVITY
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Dioxygen Affinities and Catalytic Epoxidation Performanceof Transition-Metal Hydroxamates 被引量:9
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作者 Hua YANG Sheng Ying QIN Xiao Xia LU(Department of Chemistry, Sichuan University, Chengdu 610064) 《Chinese Chemical Letters》 SCIE CAS CSCD 1999年第1期79-82,共4页
The dioxygen affinities and catalytic epoxidation performance of transition-metal hydroxamates were investigated for the first time. The effects of substituents on these properties were also discussed in the paper.
关键词 transition-metal hydroxamates dioxygen affinities catalytic epoxidation
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Destruction of VOCs by combination of corona discharge and catalysis techniques 被引量:3
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作者 Muhammad Arif Malik Jiang Xuan zhen 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1998年第3期21-26,共6页
The catalytic effect of alumina on the destruction of toluene, benzene, acetone and methanol, in DC pulsed corona discharge reactor was studied. In the presence of alumina the inlet concentration of the VOCs was varie... The catalytic effect of alumina on the destruction of toluene, benzene, acetone and methanol, in DC pulsed corona discharge reactor was studied. In the presence of alumina the inlet concentration of the VOCs was varied from ~5×10-6 mol/L to ~80×10-6 mol/L, and their decomposition efficiency (conversion %) was found to be 99%-80% for toluene, 99%-97% for benzene, 95%-92% for acetone, and 72%-85% for methanol. Corresponding decomposition in the absence of alumina was 90%-38% for toluene, 89%-57% for benzene, 42%-30% for acetone, and 47%-19% for methanol. Feed gas flow rate was 400 cm 3/min and power reading from DC source was 74 W in all of the experiments. Alumina also shifted the CO/CO 2 ratio in the by products in favor of CO 2. Ozone concentration at the reactor outlet was higher in the presence of alumina. Enhancement in VOCs decomposition by alumina was explained on the basis of higher concentration of ozone and its precursor atomic oxygen O . Decomposition efficiency (conversion %) for individual compounds was found to be inversely proportional to the ionization potential of the compound, under identical conditions. Double DC high voltage sources pulse generator was tested and found to improve VOCs decomposition compared with the conventional single DC high voltage source. 展开更多
关键词 corona discharge catalysis techniques VOCS decomposition efficiency.
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Structure, synthesis, and catalytic properties of nanosize cerium-zirconium-based solid solutions in environmental catalysis 被引量:20
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作者 Jixing Liu Zhen Zhao +1 位作者 Chunming Xu Jian Liu 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2019年第10期1438-1487,共50页
Nanosize cerium-zirconium solid solution(CZO)with a special fluorite structure has received an increasing research interest due to their remarkable advantages such as excellent oxygen storage capacity and great flexib... Nanosize cerium-zirconium solid solution(CZO)with a special fluorite structure has received an increasing research interest due to their remarkable advantages such as excellent oxygen storage capacity and great flexibility in their composition and structure.By partial metal(including rare earth,transition,alkaline earth or other metal)doping into CZO,the physicochemical properties of these catalytic materials can be controllable adjusted for the study of specific reactions.To date,nanosize CZO has been prepared by co-precipitation,sol-gel,surfactant-assisted approach,solution combustion,micro-emulsion,high energy mechanical milling,etc.The advent of these methodologies has prompted researchers to construct well-defined networks with customized micromorphology and functionalities.In this review,we describe not only the basic structure and synthetic strategies of CZO,but also their relevant applications in environmental catalysis,such as the purification for CO,nitrogen oxides(NOx),volatile organic compounds(VOC),soot,hydrocarbon(HC),CO2 and solid particulate matters(PM),and some reaction mechanisms are also summarized. 展开更多
关键词 Cerium-zirconium solid solution SYNTHESIS Method STRUCTURE Environmental catalysis
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Application of in-plasma catalysis and post-plasma catalysis for methane partial oxidation to methanol over a Fe_2O_3-CuO/γ-Al_2O_3 catalyst 被引量:5
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作者 Lin Chen Xingwang Zhang +1 位作者 Liang Huang Lecheng Lei 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2010年第6期628-637,共10页
Methane partial oxidation to methanol (MPOM) using dielectric barrier discharge over a Fe2O3-CuO/γ-Al2O3 catalyst was performed.The multicomponent catalyst was combined with plasma in two different configurations,i... Methane partial oxidation to methanol (MPOM) using dielectric barrier discharge over a Fe2O3-CuO/γ-Al2O3 catalyst was performed.The multicomponent catalyst was combined with plasma in two different configurations,i.e.,in-plasma catalysis (IPC) and post-plasma catalysis (PPC).It was found that the catalytic performance of the catalysts for MPOM was strongly dependent on the hybrid configuration.A better synergistic performance of plasma and catalysis was achieved in the IPC configuration,but the catalysts packed in the discharge zone showed lower stability than those connected to the discharge zone in sequence.Active species,such as ozone,atomic oxygen and methyl radicals,were produced from the plasma-catalysis process,and made a major contribution to methanol synthesis.These active species were identified by the means of in situ optical emission spectra,ozone measurement and FT-IR spectra.It was confirmed that the amount of active species in the IPC system was greater than that in the PPC system.The results of TG,XRD,and N2 adsorption-desorption revealed that carbon deposition on the spent catalyst surface was responsible for the catalyst deactivation in the IPC configuration. 展开更多
关键词 methane partial oxidation to methanol plasma catalysis combination synergistic performance catalytic stability
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