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Progress in MOF-based catalyst design and reaction mechanisms for CO_(2)hydrogenation to methanol
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作者 YU Zhifu JIANG Lei WU Mingbo 《燃料化学学报(中英文)》 北大核心 2026年第1期146-162,共17页
Against the backdrop of escalating global climate change and energy crises,the resource utilization of carbon dioxide(CO_(2)),a major greenhouse gas,has become a crucial pathway for achieving carbon peaking and carbon... Against the backdrop of escalating global climate change and energy crises,the resource utilization of carbon dioxide(CO_(2)),a major greenhouse gas,has become a crucial pathway for achieving carbon peaking and carbon neutrality goals.The hydrogenation of CO_(2)to methanol not only enables carbon sequestration and recycling,but also provides a route to produce high value-added fuels and basic chemical feedstocks,holding significant environmental and economic potential.However,this conversion process is thermodynamically and kinetically limited,and traditional catalyst systems(e.g.,Cu/ZnO/Al_(2)O_(3))exhibit inadequate activity,selectivity,and stability under mild conditions.Therefore,the development of novel high-performance catalysts with precisely tunable structures and functionalities is imperative.Metal-organic frameworks(MOFs),as crystalline porous materials with high surface area,tunable pore structures,and diverse metal-ligand compositions,have the great potential in CO_(2)hydrogenation catalysis.Their structural design flexibility allows for the construction of well-dispersed active sites,tailored electronic environments,and enhanced metal-support interactions.This review systematically summarizes the recent advances in MOF-based and MOF-derived catalysts for CO_(2)hydrogenation to methanol,focusing on four design strategies:(1)spatial confinement and in situ construction,(2)defect engineering and ion-exchange,(3)bimetallic synergy and hybrid structure design,and(4)MOF-derived nanomaterial synthesis.These approaches significantly improve CO_(2)conversion and methanol selectivity by optimizing metal dispersion,interfacial structures,and reaction pathways.The reaction mechanism is further explored by focusing on the three main reaction pathways:the formate pathway(HCOO*),the RWGS(Reverse Water Gas Shift reaction)+CO*hydrogenation pathway,and the trans-COOH pathway.In situ spectroscopic studies and density functional theory(DFT)calculations elucidate the formation and transformation of key intermediates,as well as the roles of active sites,metal-support interfaces,oxygen vacancies,and promoters.Additionally,representative catalytic performance data for MOFbased systems are compiled and compared,demonstrating their advantages over traditional catalysts in terms of CO_(2)conversion,methanol selectivity,and space-time yield.Future perspectives for MOF-based CO_(2)hydrogenation catalysts will prioritize two main directions:structural design and mechanistic understanding.The precise construction of active sites through multi-metallic synergy,defect engineering,and interfacial electronic modulation should be made to enhance catalyst selectivity and stability.In addition,advanced in situ characterization techniques combined with theoretical modeling are essential to unravel the detailed reaction mechanisms and intermediate behaviors,thereby guiding rational catalyst design.Moreover,to enable industrial application,challenges related to thermal/hydrothermal stability,catalyst recyclability,and cost-effective large-scale synthesis must be addressed.The development of green,scalable preparation methods and the integration of MOF catalysts into practical reaction systems(e.g.,flow reactors)will be crucial for bridging the gap between laboratory research and commercial deployment.Ultimately,multi-scale structure-performance optimization and catalytic system integration will be vital for accelerating the industrialization of MOF-based CO_(2)-to-methanol technologies. 展开更多
关键词 CO_(2)hydrogenation metal-organic frameworks(MOFs) catalyst design reaction mechanism METHANOL
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Advanced isoconversional kinetic analysis of lepidolite sulfation product decomposition reactions for selectively extracting lithium
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作者 Yubo Liu Baozhong Ma +4 位作者 Jiahui Cheng Xiang Li Hui Yang Chengyan Wang Yongqiang Chen 《International Journal of Minerals,Metallurgy and Materials》 2026年第1期217-227,共11页
The sulfation and decomposition process has proven effective in selectively extracting lithium from lepidolite.It is essential to clarify the thermochemical behavior and kinetic parameters of decomposition reactions.A... The sulfation and decomposition process has proven effective in selectively extracting lithium from lepidolite.It is essential to clarify the thermochemical behavior and kinetic parameters of decomposition reactions.Accordingly,comprehensive kinetic study by employing thermalgravimetric analysis at various heating rates was presented in this paper.Two main weight loss regions were observed during heating.The initial region corresponded to the dehydration of crystal water,whereas the subsequent region with overlapping peaks involved complex decomposition reactions.The overlapping peaks were separated into two individual reaction peaks and the activation energy of each peak was calculated using isoconversional kinetics methods.The activation energy of peak 1 exhibited a continual increase as the reaction conversion progressed,while that of peak 2 steadily decreased.The optimal kinetic models,identified as belonging to the random nucleation and subsequent growth category,provided valuable insights into the mechanism of the decomposition reactions.Furthermore,the adjustment factor was introduced to reconstruct the kinetic mechanism models,and the reconstructed models described the kinetic mechanism model more accurately for the decomposition reactions.This study enhanced the understanding of the thermochemical behavior and kinetic parameters of the lepidolite sulfation product decomposition reactions,further providing theoretical basis for promoting the selective extraction of lithium. 展开更多
关键词 LITHIUM LEPIDOLITE decomposition reactions KINETICS isoconversional analysis
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Solar-Driven Redox Reactions with Metal Halide Perovskites Heterogeneous Structures
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作者 Qing Guo Jin‑Dan Zhang +1 位作者 Jian Li Xiyuan Feng 《Nano-Micro Letters》 2026年第2期337-367,共31页
Metal halide perovskites(MHPs)with striking electrical and optical properties have appeared at the forefront of semiconductor materials for photocatalytic redox reactions but still suffer from some intrinsic drawbacks... Metal halide perovskites(MHPs)with striking electrical and optical properties have appeared at the forefront of semiconductor materials for photocatalytic redox reactions but still suffer from some intrinsic drawbacks such as inferior stability,severe charge-carrier recombination,and limited active sites.Heterojunctions have recently been widely constructed to improve light absorption,passivate surface for enhanced stability,and promote charge-carrier dynamics of MHPs.However,little attention has been paid to the review of MHPs-based heterojunctions for photocatalytic redox reactions.Here,recent advances of MHPs-based heterojunctions for photocatalytic redox reactions are highlighted.The structure,synthesis,and photophysical properties of MHPs-based heterojunctions are first introduced,including basic principles,categories(such as Schottky junction,type-I,type-II,Z-scheme,and S-scheme junction),and synthesis strategies.MHPs-based heterojunctions for photocatalytic redox reactions are then reviewed in four categories:H2evolution,CO_(2)reduction,pollutant degradation,and organic synthesis.The challenges and prospects in solar-light-driven redox reactions with MHPs-based heterojunctions in the future are finally discussed. 展开更多
关键词 Metal halide perovskite HETEROJUNCTION Redox reaction Solar-to-chemical conversion
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Fe-loaded S,N co-doped carbon catalyst for oxygen reduction reaction with enhanced electrocatalytic activity and durability
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作者 Shengzhi He Chunwen Sun 《International Journal of Minerals,Metallurgy and Materials》 2026年第1期315-321,共7页
Heteroatom-doped carbon is considered a promising alternative to commercial Pt/C as an efficient catalyst for the oxygen reduction reaction(ORR).This study presents the synthesis of iron-loaded,sulfur and nitrogen co-... Heteroatom-doped carbon is considered a promising alternative to commercial Pt/C as an efficient catalyst for the oxygen reduction reaction(ORR).This study presents the synthesis of iron-loaded,sulfur and nitrogen co-doped carbon(Fe/SNC)via in situ incorporation of 2-aminothiazole molecules into zeolitic imidazolate framework-8(ZIF-8)through coordination between metal ions and organic ligands.Sulfur and nitrogen doping in carbon supports effectively modulates the electronic structure of the catalyst,increases the Brunauer-Emmett-Teller surface area,and exposes more Fe-N_(x)active centers.Fe-loaded,S and N co-doped carbon with Fe/S molar ratio of 1:10(Fe/SNC-10)exhibits a half-wave potential of 0.902 V vs.RHE.After 5000 cycles of cyclic voltammetry,its half-wave potential decreases by only 20 mV vs.RHE,indicating excellent stability.Due to sulfur s lower electronegativity,the electronic structure of the Fe-N_(x)active center is modulated.Additionally,the larger atomic radius of sulfur introduces defects into the carbon support.As a result,Fe/SNC-10 demonstrates superior ORR activity and stability in alkaline solution compared with Fe-loaded N-doped carbon(Fe/NC).Furthermore,the zinc-air battery assembled with the Fe/SNC-10 catalyst shows enhanced performance relative to those assembled with Fe/NC and Pt/C catalysts.This work offers a novel design strategy for advanced energy storage and conversion applications. 展开更多
关键词 zinc-air batteries oxygen reduction reaction iron-loaded nitrogen-doped carbon sulfur-doping
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Recent Advances in Regulation Strategy and Catalytic Mechanism of Bi-Based Catalysts for CO_(2) Reduction Reaction
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作者 Jianglong Liu Yunpeng Liu +5 位作者 Shunzheng Zhao Baotong Chen Guang Mo Zhongjun Chen Yuechang Wei Zhonghua Wu 《Nano-Micro Letters》 2026年第1期647-697,共51页
Using photoelectrocatalytic CO_(2) reduction reaction(CO_(2)RR)to produce valuable fuels is a fascinating way to alleviate environmental issues and energy crises.Bismuth-based(Bi-based)catalysts have attracted widespr... Using photoelectrocatalytic CO_(2) reduction reaction(CO_(2)RR)to produce valuable fuels is a fascinating way to alleviate environmental issues and energy crises.Bismuth-based(Bi-based)catalysts have attracted widespread attention for CO_(2)RR due to their high catalytic activity,selectivity,excellent stability,and low cost.However,they still need to be further improved to meet the needs of industrial applications.This review article comprehensively summarizes the recent advances in regulation strategies of Bi-based catalysts and can be divided into six categories:(1)defect engineering,(2)atomic doping engineering,(3)organic framework engineering,(4)inorganic heterojunction engineering,(5)crystal face engineering,and(6)alloying and polarization engineering.Meanwhile,the corresponding catalytic mechanisms of each regulation strategy will also be discussed in detail,aiming to enable researchers to understand the structure-property relationship of the improved Bibased catalysts fundamentally.Finally,the challenges and future opportunities of the Bi-based catalysts in the photoelectrocatalytic CO_(2)RR application field will also be featured from the perspectives of the(1)combination or synergy of multiple regulatory strategies,(2)revealing formation mechanism and realizing controllable synthesis,and(3)in situ multiscale investigation of activation pathways and uncovering the catalytic mechanisms.On the one hand,through the comparative analysis and mechanism explanation of the six major regulatory strategies,a multidimensional knowledge framework of the structure-activity relationship of Bi-based catalysts can be constructed for researchers,which not only deepens the atomic-level understanding of catalytic active sites,charge transport paths,and the adsorption behavior of intermediate products,but also provides theoretical guiding principles for the controllable design of new catalysts;on the other hand,the promising collaborative regulation strategies,controllable synthetic paths,and the in situ multiscale characterization techniques presented in this work provides a paradigm reference for shortening the research and development cycle of high-performance catalysts,conducive to facilitating the transition of photoelectrocatalytic CO_(2)RR technology from the laboratory routes to industrial application. 展开更多
关键词 Bismuth-based catalysts CO_(2)reduction reaction Regulation strategy Catalytic mechanism REVIEW
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Direct partial oxidation of methane to methanol:Reaction zones and role of catalyst location 被引量:3
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作者 Qijian Zhang Dehua He Qiming Zhu 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2008年第1期24-28,共5页
Direct partial oxidation of methane to methanol was investigated in a specially designed reactor. Methanol yield of about 7%-8% was obtained in gas phase partial oxidation. It was proposed that the reactor could be di... Direct partial oxidation of methane to methanol was investigated in a specially designed reactor. Methanol yield of about 7%-8% was obtained in gas phase partial oxidation. It was proposed that the reactor could be divided into three reaction zones, namely pre-reaction zone, fierce reaction zone, and post-reaction zone, when the temperature was high enough to initiate a reaction. The oxidation of methane proceeded and was completed mostly in the fierce reaction zone. When the reactant mixture entered the post-reaction zone, only a small amount of produced methanol would bring about secondary reactions, because molecular oxygen had been exhausted in the fierce reaction zone. A catalyst, if necessary, should be placed either in the pre-reaction zone, to initiate a partial oxidation reaction at a lower temperature, or in the fierce reaction zone to control the homogeneous free radical reaction. 展开更多
关键词 METHANE METHANOL partial oxidation reaction zone role of catalyst
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Chromosomal Constitutions and Reactions to Powdery Mildew and Stripe Rust of Four Novel Wheat-Thinopyrum intermedium Partial Amphiploids 被引量:10
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作者 Yinguang Bao Xia Wu +4 位作者 Chao Zhang Xingfeng Li Fang He Xiaolei Qi Honggang Wang 《Journal of Genetics and Genomics》 SCIE CAS CSCD 2014年第12期663-666,共4页
As a staple food crop for one-third of the world's population, common wheat (Triticum aestivum L., 2n = 6x = 42, AABBDD) plays an important role in humans' food security. However, the genetic variation of cultivat... As a staple food crop for one-third of the world's population, common wheat (Triticum aestivum L., 2n = 6x = 42, AABBDD) plays an important role in humans' food security. However, the genetic variation of cultivated wheat has been dramatically narrowed by genetic erosion under the modem cultivation system, resulting in vulnerability to biotic and abiotic stresses (Jiang et al., 1994; Friebe et al., 1996). The wild relatives of wheat represent a large reservoir of superior genes, and transferring these alien genes to modem cultivars through chromosome engineering is a successful method of broadening the genetic diversity of wheat (Chen et al., 2003; 展开更多
关键词 Th TE Chromosomal Constitutions and reactions to Powdery Mildew and Stripe Rust of Four Novel Wheat-Thinopyrum intermedium partial Amphiploids St
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Scattering Resonance States and Partial Potential Energy Surface of Reaction I+HI(v=0)→IH(v′=0) +I 被引量:1
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作者 SUN Xiao-min WANG Hua-yang +2 位作者 CAI Zheng-ting FENG Da-cheng BIAN Wen-sheng 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2005年第5期569-572,共4页
The partial potential energy surface of the I + HI →IH + I reaction involving the translational and vibrational motions has been constructed at the QCISD( T )//MP4SDQ level with the pseudo potential method that i... The partial potential energy surface of the I + HI →IH + I reaction involving the translational and vibrational motions has been constructed at the QCISD( T )//MP4SDQ level with the pseudo potential method that is helpful to interpreting the scattering resonance states. The lifetimes of the scattering resonance states in the title reaction obtained from the partial potential energy surface are about 90-120 fs, which agrees with the result of high-resolved threshold photodetachment spectroscopy of anion IHI^- measured by Neumark. 展开更多
关键词 partial potential energy surface reaction pathway Dynamic Eyring Lake Scattering resonance state Lifetime of resonance
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Improved oxygen reduction reaction via a partially oxidized Co-CoO catalyst on N-doped carbon synthesized by a facile sand-bath method 被引量:5
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作者 Libing Hu Feng Yu +7 位作者 Huifang Yuan Gang Wang Mincong Liu Lina Wang Xueyan Xue Banghua Peng Zhiqun Tian Bin Dai 《Chinese Chemical Letters》 SCIE CAS CSCD 2019年第3期624-629,共6页
High active and durable non-noble metal electrocatalysts are urgently developed to satisfy the high performance oxygen reduction reaction(ORR). We successfully synthesized Co-CoOx anchored on nitrogen-doped carbon via... High active and durable non-noble metal electrocatalysts are urgently developed to satisfy the high performance oxygen reduction reaction(ORR). We successfully synthesized Co-CoOx anchored on nitrogen-doped carbon via a facile sand-bath method(SBM), i.e., Co-CoOx/N-C(SBM). The as-obtained Co-CoOx/N-C(SBM) exhibited overwhelming superiorities to Co-CoO/N-C prepared by conventional heat treatment(CHT), particularly in electrochemical performance of ORR. Although Co-CoOx/N-C(SBM)showed smaller specific surface area of 276.8 m^2/g than that of 939.5 m^2/g from Co-CoO/N-C(CHT), the Co-CoOx/N-C(SBM) performed larger pore diameter and more Co_3O_4 active component resulting in better ORR performance in 0.1 mol/L KOH solution. The Co-CoO_x/N-C(SBM) delivered onset potential of 0.91 V vs. RHE, mid-wave potential of 0.85 V vs. RHE and limited current density of 5.46 mA/cm^2 much better than those of the Co-CoO/N-C(CHT). Furthermore, Co-CoOx/N-C(SBM) showed greater stability and better methanol tolerance superior to the commercial 20 wt% Pt/C. 展开更多
关键词 Oxygen reduction reaction Fuel cell ELECTROCATALYST Cobalt oxide Energy conversion
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Effect of calcination temperature and reaction conditions on methane partial oxidation using lanthanum-based perovskite as oxygen donor 被引量:4
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作者 代小平 余长春 +3 位作者 李然家 吴琼 史凯娇 郝郑平 《Journal of Rare Earths》 SCIE EI CAS CSCD 2008年第3期341-346,共6页
We investigated the effect of calcination temperature, reaction temperature, and different amounts of replenished lattice oxygen on the partial oxidation of methane (POM) to synthesis gas using perovskite-type LaFeO... We investigated the effect of calcination temperature, reaction temperature, and different amounts of replenished lattice oxygen on the partial oxidation of methane (POM) to synthesis gas using perovskite-type LaFeO3 oxide as oxygen donor instead of gaseous oxygen, which was prepared by the sol-gel method, and the oxides were characterized by XRD, TG/DTA, and BET. The results indicated that the particle size increased with the calcination temperature increasing, while BET and CH4 conversion declined with the calcination temperature increasing using LaFeO3 oxide as oxygen donor in the absence of gaseous oxygen. CO selectivity remained at a high level such as above 92%, and increased slightly as the calcination temperature increased. Exposure of LaFeO3 oxides to methane atmosphere enhanced the oxygen migration of in the bulk with time online owing to the loss of lattice oxygen and reduction of the oxidative stated Fe ion simultaneously, The high reaction temperature was favorable to the migration of oxygen species from the bulk toward the surface for the synthesis gas production with high CO selectivity. The product distribution and evolution for POM by sequential redox reaction was determined by amounts of replenished lattice oxygen with gaseous oxygen. The optimal process should decline the total oxidation of methane, and increase the selectivity of partial oxidation of methane. 展开更多
关键词 perovskite LaFeO3 lattice oxygen synthesis gas redox reaction rare earths
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Effects of the partial replacement of La by M(M=Ce,Ca and Sr) in La_(2-x)M_xCuO_4 perovskites on catalysis of the water-gas shift reaction 被引量:2
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作者 S.S.Maluf E.M.Assaf 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2010年第6期567-574,共8页
The performance of La2-x M x CuO4 perovskites (where M=Ce,Ca or Sr) as catalysts for the water-gas shift reaction was investigated at 290℃ and 360℃.The catalysts were characterized by EDS,XRD,N2 adsorption-desorpt... The performance of La2-x M x CuO4 perovskites (where M=Ce,Ca or Sr) as catalysts for the water-gas shift reaction was investigated at 290℃ and 360℃.The catalysts were characterized by EDS,XRD,N2 adsorption-desorption,XPS and XANES.The XRD results showed that all the perovskites exhibited a single phase (the presence of perovskite structure),suggesting the incorporation of metals in the perovskite structure.The XPS and XANES results showed the presence of Cu2+ on the surface.The perovskites that exhibited the best catalytic performance were La 2 x Ce x CuO 4 perovskites,with CO conversions of 85% 90%.Moreover,these perovskites have higher surface areas and larger amounts of Cu on the surface.And Ce has a higher filled energy level than the other metals,increasing the energy of the valence band of Ce and providing more electrons for the reaction.Besides,the La1.80Ca0.20CuO4 perovskite showed a good catalytic performance. 展开更多
关键词 perovskites water-gas shift reaction LANTHANUM copper calcium CERIUM STRONTIUM
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Interfacial reactions and diffusion path in partial transient liquid-phase bonding of Si_3N_4/Ti/Ni/Ti/Si_3N_4 被引量:1
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作者 陈铮 赵其章 +3 位作者 方芳 楼宏青 睦润舟 李志章 《中国有色金属学会会刊:英文版》 CSCD 1999年第4期831-837,共7页
The interfacial reactions in partial transient liquid-phase bonding of Si3N4 ceramics with Ti/Ni/Ti interlayers were studied by means of scanning electron microscopy (SEM), energy dispersive spectrometry (EDS) and... The interfacial reactions in partial transient liquid-phase bonding of Si3N4 ceramics with Ti/Ni/Ti interlayers were studied by means of scanning electron microscopy (SEM), energy dispersive spectrometry (EDS) and X-ray diffractometry (XRD). It was shown that the interfacial structure of Si3N4/TiN/Ti5Si3+Ti5Si4 + Ni3Si/ (NiTi ) /Ni3Ti/ Ni was formed after bonding. The activation energies for TiN layer and the mixed reaction layer of Ti5Si3 + Ti5Si4 + Ni3Si are 546. 8 kJ/mol and 543. 9 kJ/mol, respectively. The formation and transition processes of interface layer sequence in the joint were clarified by diffusion path. An important characteristic, which is different from the conventional brazing and soid-state diffusion bonding, has been found, i. e., during the partial transient liquid-phase bonding, not only the reaction layers which have formed grow, but also the diffusion path in the subsequent reaction changes because of the remarkable variation of the concentration on the metal side. 展开更多
关键词 CERAMIC joining transient LIQUID-PHASE BONDING INTERFACIAL reactionS diffusion
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Effects of Partially N-acetylated Chitosans to Elicit Resistance Reaction on Brassica napus L. 被引量:1
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作者 ZHANG Xue-kun, TANG Zhang-lin, CHEN Li, GUO Yi-hong, CHEN Yun-ping and LI Jia-na(Agronomy Department, Southwest Agricultural University , Chongqing 400716 , China) 《Agricultural Sciences in China》 CAS CSCD 2002年第5期516-519,共4页
The effects to elicit resistance reaction on oilseed rape (Brassica napus L. cv Xinongchangjiao ) by four partially N-acetylated chitosan 7B, 8B, 9B and 10B (Degree of acetylation (D. A.) is 30% , 20% , 10%, 0%, respe... The effects to elicit resistance reaction on oilseed rape (Brassica napus L. cv Xinongchangjiao ) by four partially N-acetylated chitosan 7B, 8B, 9B and 10B (Degree of acetylation (D. A.) is 30% , 20% , 10%, 0%, respectively) and Glycol chitosan (GC, D.A. is 0%) were investigated and compared. Results showed that chitosan were similar to salicylic acid (SA), and could induce resistance reaction, but the reaction was influenced by the degree of acetylation of chitosan. Fully deacetylated chitosans, 10B and GC, elicited chitinase activity, but partially acetylated chitosan, 7B, 8B and 9B, inhibited chitinase activity. Phenyalanine ammonia-lyase (PAL) was also elicited. Elicitor activity increased with on increasing degree of acetylation, 7B induced highest PAL activity among all chitosans. All chitosans induced peroxidase (POD) in a similar level. After elicited by glycol chitosan, like SA treatment, the seedlings increased disease resistance to Sclerotinia sclerotiorum significantly. 展开更多
关键词 Brassica napus L. CHITOSAN Degree of acetylation Resistance reaction
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Effect of Ni Loading and Reaction Conditions on Partial Oxidation of Methane to Syngas
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作者 Haitao Wang, Zhenhua Li, Shuxun TianSchool of Chemical Engineering and Technology, Tianjin University, Tianjin 300072, China 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2003年第3期205-209,共5页
The partial oxidation of methane to synthesis gas is studied in this paperover Ni/Al_2O_3 catalysts under atmospheric pressure. The effects of Ni loading on the activity andstability of catalysts with 5 mm α-Al_2O_3 ... The partial oxidation of methane to synthesis gas is studied in this paperover Ni/Al_2O_3 catalysts under atmospheric pressure. The effects of Ni loading on the activity andstability of catalysts with 5 mm α-Al_2O_3 and θ-Al_2O_3 pellets as supports were measured in acontinuous fixed bed reactor. It is found that the optimum Ni loading is 10%. And the effect ofreaction conditions on partial oxidation of methane is also studied. The methane conversion and COselectivity increase with the increase of the reaction temperature and the space velocity on10%Ni/α-Al_2O_3 catalysts. The best CH_4/O_2 mole ratio is 2 for CO selectivity, and the optimumspace velocity is 5.4x10^5 h^(1). 展开更多
关键词 METHANE SYNGAS NICKEL partial oxidation ALUMINA
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Extraction of symmetry energy coefficient in heavy-ion reactions near the Fermi energies
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作者 冷强钟 曲国峰 +8 位作者 黄宇 张鑫 段茜 陈婉君 林炜平 郑华 任培培 刘星泉 韩纪锋 《四川大学学报(自然科学版)》 北大核心 2025年第1期153-161,共9页
An improved method is proposed for the extraction of the symmetry energy coefficient relative to the temperature,a_(sym)/T,in the heavy-ion reactions near the Fermi energy region,based on the modified Fisher Model.Thi... An improved method is proposed for the extraction of the symmetry energy coefficient relative to the temperature,a_(sym)/T,in the heavy-ion reactions near the Fermi energy region,based on the modified Fisher Model.This method is applied to the primary fragments of antisymmetrized molecular dynamics(AMD)simulations for ^(46)Fe+^(46)Fe,^(40)Ca+^(40)Ca and ^(48)Ca+^(48)Ca at 35 MeV/nucleon,in order to make direct comparison to the results from the K(N,Z)method of Ono et al.In our improved method,the extracted values of a_(sym)/T increase as the size of isotopes increases whereas,in the K(N,Z)method,the results show rather constant behavior.This increase in our result is attributed to the surface contribution of the symmetry energy in finite nuclei.In order to evaluate the surface contribution,the relation a_(sym)/T=[a_(sym)^((V))(1-k_(S/V) A^(-1/3))]/T is applied and k_(S/V)=1.20~1.25 was extracted.This value is smaller than those extracted from the mass table,reflecting the weakened surface contribution at higher temperature regime.Δμ/T,the difference of the neutron-proton chemical potentials relative to the temperature,is also extracted in this method at the same time.The average values of the extractedΔμ/T,Δμ/T show a linear dependence on the proton-neutron a_(sym)metry parameter of the system,δ_(sys),andΔμ/T=(15.1±0.2)δ_(sys)-(0.5±0.1)is obtained. 展开更多
关键词 Heavy-ion reactions Symmetry energy Antisymmetrized molecular dynamics model
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一种相关观测Partial EIV模型的三维激光扫描标靶球定位方法
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作者 熊露雲 曾堃 +2 位作者 李耀斌 刘志辉 杨光 《工程勘察》 2025年第12期47-52,共6页
针对三维激光标靶球定位模型中的系数矩阵存在随机元素和非随机元素以及考虑到观测向量与系数矩阵存在相关的情况,引入基于Partial EIV模型的相关观测加权总体最小二乘(Weighted Total Least Squares,WTLS)方法进行求解。模拟实验结果表... 针对三维激光标靶球定位模型中的系数矩阵存在随机元素和非随机元素以及考虑到观测向量与系数矩阵存在相关的情况,引入基于Partial EIV模型的相关观测加权总体最小二乘(Weighted Total Least Squares,WTLS)方法进行求解。模拟实验结果表明,在顾及观测向量与系数矩阵存在相关性时,基于Partial EIV模型的相关观测加权总体最小二乘方法解算的参数结果更加接近真值,且精度更高。进一步将该方法应用于实际案例数据中,结果表明,在实际计算时有必要考虑到观测向量与系数矩阵之间的相关性,以提高参数解算精度。本文可补充和完善三维激光扫描标靶球定位技术方法。 展开更多
关键词 标靶球定位 partial EIV模型 加权总体最小二乘 相关观测
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Theoretical Study of the Scattering Resonance State, Reaction Mechanism and Partial Potential Energy Surface of the F+CH4→HF+CH3 Reaction
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作者 Qiang WANG Zheng Ting CAI Da Cheng FENG 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第2期281-284,共4页
The partial potential energy surface was constructed by ab initio method [QCISD(T)/6- 311++G(2df,2pd)]for F+CH4→HF+CH3 reaction system. It not only explained the reaction mechanism brought forward by Diego Tr... The partial potential energy surface was constructed by ab initio method [QCISD(T)/6- 311++G(2df,2pd)]for F+CH4→HF+CH3 reaction system. It not only explained the reaction mechanism brought forward by Diego Troya by means of quasiclassical trajectory (QCT) but also successfully validated Kopin Liu's experimental phenomena about the existence of the reactive resonance. The lifetime of the scattering resonance state was about 0.07 ps. All these were in agreement with the experiments. 展开更多
关键词 The partial potential energy surface (PPES) asymmetrical heavy-light-heavy system dynamic Eyring lake the lifetime of the scattering resonance state.
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A Cu-Pd alloy catalyst with partial phase separation for the electrochemical CO_(2) reduction reaction
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作者 Gyeong Ho Han Jung Yong Seo +4 位作者 Minji Kang Myung-gi Seo Youngheon Choi Soo Young Kim Sang Hyun Ahn 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第6期8-15,I0001,共9页
Cu catalysts can convert CO_(2) through an electrochemical reduction reaction into a variety of useful carbon-based products.However,this capability provides an obstacle to increasing the selectivity for a single prod... Cu catalysts can convert CO_(2) through an electrochemical reduction reaction into a variety of useful carbon-based products.However,this capability provides an obstacle to increasing the selectivity for a single product.Herein,we report a simple fabrication method for a Cu-Pd alloy catalyst for use in a membrane electrode assembly(MEA)-based CO_(2) electrolyzer for the electrochemical CO_(2) reduction reaction(ECRR)with high selectivity for CO production.When the composition of the Cu-Pd alloy catalyst was fabricated at 6:4,the selectivity for CO increased and the production of multi-carbon compounds and hydrogen is suppressed.Introducing a Cu-Pd alloy catalyst with 6:4 ratio as the cathode of the MEAbased CO_(2) electrolyzer showed a CO faradaic efficiency of 92.8%at 2.4 V_(cell).We assumed that these results contributed from the crystal planes on the surface of the Cu-Pd alloy.The phases of the Cu-Pd alloy catalyst were partially separated through annealing to fabricate a catalyst with high selectivity for CO at low voltage and C_(2)H_4 at high voltage.The results of CO-stripping testing confirmed that when Cu partially separates from the lattice of the Cu-Pd alloy,the desorption of~*CO is suppressed,suggesting that C-C coupling reaction is favored. 展开更多
关键词 Cu-Pd catalyst ELECTRODEPOSITION Electrochemical carbon dioxide reduction partial phase separation Membrane electrode assembly-based electrolyzer
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Reaction Infiltration Instabilities in Partially Molten Peridotite and Implications for Driving the Transport of Sulfide Liquid
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作者 Zhenjiang Wang Zhenmin Jin 《Journal of Earth Science》 SCIE CAS CSCD 2020年第3期447-455,共9页
Reaction infiltration instability(RII)can cause the formation of melt channels and potentially facilitate the physical transport of sulfide liquid,which contributes to the geochemical evolution of chalcophile elements... Reaction infiltration instability(RII)can cause the formation of melt channels and potentially facilitate the physical transport of sulfide liquid,which contributes to the geochemical evolution of chalcophile elements in the lithospheric mantle.This study conducted some two-layer reaction experiments to explore the feasibility of reaction-driven sulfide migration along high-velocity silicate-melt channels.With increasing duration,the formation of more silicate-melt channels and the transport of more sulfide droplets into a depleted peridotite were observed due to the increase of the local permeability.However,at a longer duration,the presence of some melt-channel relics implies that melt channels are temporary and ultimately closed when the reaction infiltration of silicate melt reached equilibrium in the depleted peridotite.Furthermore,theoretical calculations indicate that the RII of the system is suppressed,which impedes the formation of melt channels.The homogeneous distribution of silicate melt in a sulfide-free experiment implies that the Zener pinning of sulfide probably enhances the RII,thereby facilitating the formation of temporary melt channels.Therefore,this study demonstrates that sufficient silicate melt disequilibrium with solid phases in a liquid source potentially promotes the mechanical extraction of sulfides during reaction infiltration of silicate melt. 展开更多
关键词 high P-T experiment reaction infiltration instability sulfide liquid transport
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Liver regeneration after partial hepatectomy:Triggers and mechanisms 被引量:1
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作者 Bakari Korchilava Tamar Khachidze +5 位作者 Nino Megrelishvili Lika Svanadze Manana Kakabadze Keti Tsomaia Memed Jintcharadze Dimitri Kordzaia 《World Journal of Hepatology》 2025年第7期1-17,共17页
Liver regeneration(LR)following partial hepatectomy(PH)is a unique and complex physiological response that restores hepatic mass and function through tightly orchestrated cellular and molecular events.Traditionally vi... Liver regeneration(LR)following partial hepatectomy(PH)is a unique and complex physiological response that restores hepatic mass and function through tightly orchestrated cellular and molecular events.Traditionally viewed as a proliferation-driven process,LR is now understood to involve both hepatocyte hyperplasia and hypertrophy,triggered primarily by hemodynamic alterations such as increased portal pressure and shear stress.These promote LR through endothelial–hepatocyte communication via activation of Piezo1-a mechanosensitive ion channel highly expressed in vascular endothelial cells.This channel is considered one of the potential upstream activators of molecular cascades including the interleukin(IL)-6/signal transducer and activator of transcription 3,tumour necrosis factor-alpha/nuclear factor-kappa B,Wnt/β-catenin,Hippo/YAP,transforming growth factor-beta,and Notch pathways,which contribute variably to the proliferation,differentiation,or suppression of hepatic cells.Novel insights into the IL-22 and IL-33 signaling axes,bile acid and glutamine metabolism,and the role of intestinal microbiota are also presented as promising emerging targets.This review synthesizes current insights into the interplay between mechanical cues,key signaling pathways,and metabolic reprogramming that govern early regenerative responses.We explore the mechanisms dictating the balance between hyperplasia and hypertrophy,noting that hypertrophy predominates after minor resections,while proliferation is dominant in larger resections.Polyploidization emerges as a significant adaptive mechanism,contributing to hepatocyte survival and tissue remodeling.The importance of ductular reactions,microvascular adjustments,and extracellular matrix dynamics in lobular architecture remodeling is also highlighted.The study explores the occurrence of ductular reactions in both minor and major resections,particularly within the granulation tissue near dissection areas.The paper also examines structural remodeling in regenerated liver tissue,demonstrating ongoing transformations in hepatocyte morphology and sinusoidal architecture even months after PH,and emphasizing that the termination of liver mass regrowth does not equate to the cessation of LR. 展开更多
关键词 partial hepatectomy Liver regeneration Portal pressure Portal flow Cytokines and growth factors Molecular pathways Ductular reaction Structural remodeling
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