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“双功能、双基础、双报告”核算模式对事业单位会计核算的影响与对策研究 被引量:1
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作者 吕永枝 《当代会计》 2022年第24期128-130,共3页
新《政府会计制度》对政府会计核算提出了更高的要求,要求事业单位会计核算遵循“双功能、双基础、双报告”核算模式。文章阐述了“双功能、双基础、双报告”核算模式对事业单位会计核算的影响,探究了“双功能、双基础、双报告”核算模... 新《政府会计制度》对政府会计核算提出了更高的要求,要求事业单位会计核算遵循“双功能、双基础、双报告”核算模式。文章阐述了“双功能、双基础、双报告”核算模式对事业单位会计核算的影响,探究了“双功能、双基础、双报告”核算模式下事业单位会计核算如何实现提质增效,即在资产核算上,事业单位应当完善资产清查方式、搭建有利平台、加强对财务会计人员的培养;在收支核算上,事业单位应当注重收支核算科目的设置和使用、提高预算执行的“刚性”、完善预算监督体系。 展开更多
关键词 《政府会计制度》 “双功能” “双基础” “双报告” 事业单位
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梁披云职业教育师资思想及启示
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作者 戴汉良 李淑娥 《厦门城市职业学院学报》 2024年第2期64-69,共6页
梁披云是当代书法家、诗人、教育家和社会活动家。在70多年的教学、办学实践过程中,梁披云职业教育师资思想逐渐成熟。梁披云职业教育师资思想萌芽于大学求学期间,发展于黎明高中、福建音乐专科学校和国立海疆专科学校校长任职期间,成... 梁披云是当代书法家、诗人、教育家和社会活动家。在70多年的教学、办学实践过程中,梁披云职业教育师资思想逐渐成熟。梁披云职业教育师资思想萌芽于大学求学期间,发展于黎明高中、福建音乐专科学校和国立海疆专科学校校长任职期间,成熟于黎明职业大学校长及董事长任职期间。梁披云职业教育师资思想的主要内容:明确职业教育师资标准和建设方法,提出职业教育“双功能型”教师思想,明确“双功能型”教师道德、业务标准和建设路径。梁披云的职业教育师资思想对当前职业院校师资建设有如下启示:师德师风建设是职业教育教师资队伍建设的首要任务;“双师型”师资队伍建设是职业教育“三教”改革的重要任务;教师发展多元评价制度改革是职业教育师资队伍建设的关键任务。 展开更多
关键词 梁披云 职教师资思想 “双功能型”教师
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Kinetics of cerium(Ⅳ) and fluoride extraction from sulfuric solutions using bifunctional ionic liquid extractant(Bif-ILE)[A336][P204] 被引量:7
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作者 杨华玲 陈继 +3 位作者 张冬丽 王威 崔红敏 刘郁 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第6期1937-1945,共9页
The extraction kinetics of Ce(Ⅳ) and Ce(Ⅳ)-F^- mixture systems from sulfuric solutions to n-heptane solution containing Bif-ILE[A336][P204]([trialkylmethylammonium][di-2-ethylhewanxylphosphinate]) with a const... The extraction kinetics of Ce(Ⅳ) and Ce(Ⅳ)-F^- mixture systems from sulfuric solutions to n-heptane solution containing Bif-ILE[A336][P204]([trialkylmethylammonium][di-2-ethylhewanxylphosphinate]) with a constant interfacial area cell with laminar flow were studied,just to elucidate the extraction mechanism and the mass transfer models.The data were analyzed in terms of pseudo-first-order constants.The effects of stirring speed,specific interfacial area and temperature on the extraction rate in both systems were discussed,suggesting that the extractions were mixed bulk phases-interfacial control process.Supported by the experimental data,the corresponding rate equations for Ce(Ⅳ) extraction system and Ce(Ⅳ)-F^- mixture extraction system were obtained.The experimental results indicated the rate-controlling step.The kinetics model was deduced from the rate-controlling step and consistent with the rate equation. 展开更多
关键词 Ce(Ⅳ)-F--system Bif-ILE kinetics model extraction kinetics constant interfacial area cell with laminar flow
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Effect of Catalyst Properties on Hydrocracking of Pyrolytic Lignin to Liquid Fuel in Supercritical Ethanol 被引量:1
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作者 姚倩 唐喆 +2 位作者 郭建华 张颖 郭庆祥 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2015年第2期209-216,I0002,共9页
The metal-acid bifunctional catalysts have been used for bio-oil upgrading and pyrolytic lignin hydrocracking. In this work, the effects of the metal-acid bifunctional catalyst prop- erties, including acidity, pore si... The metal-acid bifunctional catalysts have been used for bio-oil upgrading and pyrolytic lignin hydrocracking. In this work, the effects of the metal-acid bifunctional catalyst prop- erties, including acidity, pore size and supported metal on hydrocracking of pyrolytic lignin in supercritical ethanol and hydrogen were investigated at 260 ℃. A series of catalysts were prepared and characterized by BET, XRD, and NHa-TPD techniques. The results showed that enhancing the acidity of the catalyst without metal can promote pyrolytic lignin poly- merization to form more solid and condensation to produce more water. The pore size of microporous catalyst was smaller than mesoporous catalyst. Together with strong acid- ity, it caused pyrolytic lignin further hydrocrack to numerous gas. Introducing Ru into acidic catalysts promoted pyrolytic lignin hydrocracking and inhibited the polymerization and condensation, which caused the yield of pyrolytic lignin liquefaction product to increase significantly. Therefore, bifunctional catalyst with high hydrocracking activity metal Ru supported on materials with acidic sites and mesopores was imperative to get satisfactory results for the conversion of pyrolytic lignin to liquid products under supercritical conditions and hydrogen atmosphere. 展开更多
关键词 Pyrolytic lignin HYDROCRACKING Bifunctional catalyst
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Conversion of Bio-syngas to Liquid Hydrocarbon over CuCoMn-Zeolite Bifunctional Catalysts 被引量:1
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作者 张朝霞 毕培燕 +1 位作者 姜沛汶 李全新 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2014年第5期573-581,I0004,共10页
A series of bifunctional catalysts composed of a component for higher alcohol synthesis (Cu-CoMn oxides, CCM) and an acidic zeolite (SAPO-34, ZSM-5, Y, MCM-41) were prepared for production of liquid hydrocarbon di... A series of bifunctional catalysts composed of a component for higher alcohol synthesis (Cu-CoMn oxides, CCM) and an acidic zeolite (SAPO-34, ZSM-5, Y, MCM-41) were prepared for production of liquid hydrocarbon directly from a bio-syngas through a one-stage pro-cess. The effects of zeolite type, zeolite content, Si/Al ratio and preparation method on catalyst texture and its reaction performance were investigated. Higher selectivities and yields of liquid products were obtained by using bifunctional catalysts. The yields of liquid hydrocarbons decreased in the order CCM-ZSM-5〉CCM-SAPO-34〉CCM-Y〉CCM-MCM-41. CCM-ZSM-5 (20wt%, Si/Al=100) prepared by coprecipitation method displayed the optimal catalytic performance with the highest CO conversion (76%) and yield of liquid products (30%). The catalysts were characterized by N2 adsorption/desorption, NH3-TPD, XRD, and H2-TPR analysis. The results showed that higher speci c surface areas and pore volumes of bifunctional catalysts were achieved by adding zeolites into CuCoMn precursors. Medium pore dimension and moderate acidity in CCM-ZSM-5 were observed, which proba-bly resulted in its excellent reaction performance. Additionally, a higher number of weaker acid sites (weak and/or medium acid sites) were formed by increasing ZSM-5 content in CCM-ZSM-5 or decreasing Si/Al ratio in ZSM-5. It was also seen that metal dispersion was higher and reducibility of metal ions was easier on the CCM-ZSM-5 catalyst prepared by coprecipitation. The higher alcohols-to-hydrocarbon process provides a promising route to hydrocarbon fuels via higher alcohols from syngas or biobased feedstocks. 展开更多
关键词 BIFUNCTIONAL CuCoMn-zeolite Higher alcohols-to-hydrocarbon process Bio-syngas conversion Liquid hydrocarbon synthesis
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Construction of Double Cross-over Expression Vector for Chloroplast Multicistron in Brassica napus L. 被引量:1
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作者 武玉永 姚庆收 马立新 《Agricultural Science & Technology》 CAS 2013年第3期402-406,共5页
[Objective] This study aimed to construct Brassica napus chloroplast multi- cistron double cross-over expression vector, to lay the foundation for the genetic engi- neering research of Brassica napus chloroplast. [Met... [Objective] This study aimed to construct Brassica napus chloroplast multi- cistron double cross-over expression vector, to lay the foundation for the genetic engi- neering research of Brassica napus chloroplast. [Method] Two primers were designed based on the known Brassica napus chloroplast DNA sequences AF267640 and Z50868 in GenBank. By using PCR method, two Brassica napus L. chloroplast DNA fragments were obtained, which were named RbcL and ACCD. The two Brassica na- pus chloroplast DNA homologous fragments were then cloned into plasmid pMD18-T to obtain recombinant plasmid pHBM715. Tandem expression cassette harboring spectinomycin-resistant gene aadA, mannanase gene man and green fluorescent pro- tein gene gfp was cloned into the plasmid pHBM715, thereby constructing Brassica napus chloroplast multicistron double cross-over expression vector pHBM716, which was transformed into Escherichia coil for expression and identification. [Result] Plate qualitative analysis was conducted for the functional identification of expression cas- sette in the constructed Brassica napus chloroplast multicistron double cross-over ex- pression vector, results showed that the three genes of the same multicistron were all expressed in E. coil [Conclusion] This study successfully constructed Brassica napus chloroplast multicistron double cross-over expression vector, which laid the foundation for the genetic engineering of Brassica napus chloroplast. 展开更多
关键词 Brassica napus L. Chloroplast DNA Multicistron Double cross-over Expression vector Functional identification
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Dual function of Arabidopsis A TAF1 in abiotic and biotic stress responses 被引量:60
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作者 Yaorong Wu Zhiyong Deng +8 位作者 Jianbin Lai Yiyue Zhang Cuiping Yang Bojiao Yin Qingzhen Zhao Ling Zhang Yin Li Chengwei Yang Qi Xie 《Cell Research》 SCIE CAS CSCD 2009年第11期1279-1290,共12页
NAC family genes encode plant-specific transcription factors involved in diverse biological processes. In this study, the Arabidopsis NAC gene ATAF1 was found to be induced by drought, high-salinity, abscisic acid (... NAC family genes encode plant-specific transcription factors involved in diverse biological processes. In this study, the Arabidopsis NAC gene ATAF1 was found to be induced by drought, high-salinity, abscisic acid (ABA), methyl jasmonate, mechanical wounding, and Botrytis cinerea infection. Significant induction of ATAF1 was found in an ABA-deficient mutant aba2 subjected to drought or high salinity, revealing an ABA-independent mechanism of expression. Arabidopsis ATAFl-overexpression lines displayed many altered phenotypes, including dwarfism and short primary roots. Furthermore, in vivo experiments indicate that ATAF1 is a bonafide regulator modulating plant responses to many abiotic stresses and necrotrophic-pathogen infection. Overexpression of ATAF1 in Arabidopsis increased plant sensitivity to ABA, salt, and oxidative stresses. Especially, ATAF1 overexpression plants, but not mutant lines, showed remarkably enhanced plant tolerance to drought. Additionally, ATAF1 overexpression enhanced plant susceptibility to the necrotrophic pathogen B. cinerea, but did not alter disease symptoms caused by avirulent or virulent strains of P. syringae pv tomato DC3000. Transgenic plants overexpressing ATAF1 were hypersensitive to oxidative stress, suggesting that reactive oxygen intermediates may be related to ATAFl-mediated signaling in response to both pathogen and abiotic stresses. 展开更多
关键词 abiotic stress ARABIDOPSIS ATAF1 biotic stress
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Melting-assisted solvent-free synthesis of SAPO-11 for improving the hydroisomerization performance of n-dodecane 被引量:7
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作者 Gan Yu Xinqing Chen +6 位作者 Wenjie Xue Lixia Ge Ting Wang Minghuang Qiu Wei Wei Peng Gao Yuhan sun 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2020年第4期622-630,共9页
A novel melting-assisted solvent-free route using solid oxalic acid was proposed for the post-treatment of SAPO-11 zeolite,followed by loading with 0.5 wt%Pt by the incipient wetness impregnation method.Subsequently,t... A novel melting-assisted solvent-free route using solid oxalic acid was proposed for the post-treatment of SAPO-11 zeolite,followed by loading with 0.5 wt%Pt by the incipient wetness impregnation method.Subsequently,the performance of the obtained bifunctional catalysts toward the hydroisomerization of n-dodecane was examined.The prepared samples were characterized by XRD,SEM,BET,XRF,Py-IR,and solid-state NMR.From the results,it was found that the high crystallinity and uniform morphology were retained after the post-treatment and that more(002)crystal faces were exposed,which was beneficial since more acid sites were provided.More importantly,the total Bronsted acid sites and the ratio(Ra)of the micropore area to the total surface area were optimized by this method.Thus,the catalytic performance was enhanced significantly,and the prepared Pt-SAPO-11-10%catalyst had the highest i-dodecane yield of 80.1%compared to 55.3%of Pt-SAPO-11.Expectedly,this facile and cost-effective method is promising for the hydroisomerization of normal paraffin in the production of lubricant base oils. 展开更多
关键词 HYDROISOMERIZATION Zeolite SAPO-11 Melting-assist Bifunctional catalyst
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Bifunctional electrocatalysts for rechargeable Zn-air batteries 被引量:7
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作者 Yibo Guo Ya-Nan Chen +1 位作者 Huijuan Cui Zhen Zhou 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2019年第9期1298-1310,共13页
Zn-air batteries have attracted extensive attention for their unique features including high energy density,safety,low cost and environmental friendliness.However,due to their poor chargeability and low efficiency,the... Zn-air batteries have attracted extensive attention for their unique features including high energy density,safety,low cost and environmental friendliness.However,due to their poor chargeability and low efficiency,the practical application remains a challenge.The main obstacles are the intrinsic slow reaction kinetics on air cathodes,including oxygen reduction reaction during the discharging process and oxygen evolution reaction during the recharging process.Searching for efficient bifunctional oxygen electrocatalysts is key to solve these problems.In this review,the configuration and fundamental oxygen electrochemical reactions on air cathodes are briefly introduced for Zn-air batteries first.Then,the latest bifunctional oxygen electrocatalysts are summarized in detail.Finally,the perspectives are provided for the future investigations on bifunctional oxygen electrocatalysts. 展开更多
关键词 Bifunctional electrocatalysts Oxygen-reduction reaction Oxygen-evolution reaction Zn-air batteries Hybrid materials
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Micro-nanostructural designs of bifunctional electrocatalysts for metal-air batteries 被引量:8
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作者 Fang Shi Xuefeng Zhu Weishen Yang 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2020年第3期390-403,共14页
Water-based rechargeable metal-air batteries play an important role in the storage and conversion of renewable electric energy.However,the sluggish kinetics of the oxygen reduction reaction(ORR)and oxygen evolution re... Water-based rechargeable metal-air batteries play an important role in the storage and conversion of renewable electric energy.However,the sluggish kinetics of the oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)have limited the practical application of rechargeable metal-air batteries.Most of reviews were focused on single functional electrocatalysts while few on bifunctional electrocatalysts.It is indispensable but challenging to design a bifunctional electrocatalyst that is active and stable to the two reactions.Recently,attempts to develop high active bifunctional electrocatalysts for both ORR and OER increase rapidly.Much work is focused on the micro-nano design of advanced structures to improve the performance of bifunctional electrocatalyst.Transition-metal materials,carbon materials and composite materials,and the methods developed to prepare micro-nano structures,such as electrochemical methods,chemical vapor deposition,hydrothermal methods and template methods are reported in literatures.Additionally,many strategies,such as adjustments of electronic structures,oxygen defects,metal-oxygen bonds,interfacial strain,nano composites,heteroatom doping etc.,have been used extensively to design bifunctional electrocatalysts.To well understand the achievements in the recent literatures,this review focuses on the micro-nano structural design of materials,and the related methods and strategies are classed into two groups for the improvement of intrinsic and apparent activities.The fine adjustment of nano structures and an in-depth understanding of the reaction mechanism are also discussed briefly. 展开更多
关键词 Oxygen reduction reaction Oxygen evolution reaction Rechargeable metal-air batteries Bifunctional electrocatalysts Micro-nano structure
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Effect of In_(2)O_(3)particle size on CO_(2) hydrogenation to lower olefins over bifunctional catalysts 被引量:5
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作者 Siyu Lu Haiyan Yang +4 位作者 Zixuan Zhou Liangshu Zhong Shenggang Li Peng Gao Yuhan Sun 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2021年第11期2038-2048,共11页
A reaction-coupling strategy is often employed for CO_(2)hydrogenation to produce fuels and chemicals using oxide/zeolite bifunctional catalysts.Because the oxide components are responsible for CO_(2)activation,unders... A reaction-coupling strategy is often employed for CO_(2)hydrogenation to produce fuels and chemicals using oxide/zeolite bifunctional catalysts.Because the oxide components are responsible for CO_(2)activation,understanding the structural effects of these oxides is crucial,however,these effects still remain unclear.In this study,we combined In_(2)O_(3),with varying particle sizes,and SAPO‐34 as bifunctional catalysts for CO_(2)hydrogenation.The CO_(2)conversion and selectivity of the lower olefins increased as the average In_(2)O_(3)crystallite size decreased from 29 to 19 nm;this trend mainly due to the increasing number of oxygen vacancies responsible for CO_(2) and H_(2) activation.However,In_(2)O_(3)particles smaller than 19 nm are more prone to sintering than those with other sizes.The results suggest that 19 nm is the optimal size of In_(2)O_(3)for CO_(2)hydrogenation to lower olefins and that the oxide particle size is crucial for designing catalysts with high activity,high selectivity,and high stability. 展开更多
关键词 Carbon dioxide hydrogenation Bifunctional catalysis Particle size effect Indium oxide Lower olefins
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Water-involving transfer hydrogenation and dehydrogenation of N-heterocycles over a bifunctional MoNi_(4)electrode 被引量:4
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作者 Mengyang Li Cuibo Liu +2 位作者 Yi Huang Shuyan Han Bin Zhang 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2021年第11期1983-1991,共9页
A room-temperature electrochemical strategy for hydrogenation(deuteration)and reverse dehydrogenation of N-heterocycles over a bifunctional MoNi_(4)electrode is developed,which includes the hydrogenation of quinoxalin... A room-temperature electrochemical strategy for hydrogenation(deuteration)and reverse dehydrogenation of N-heterocycles over a bifunctional MoNi_(4)electrode is developed,which includes the hydrogenation of quinoxaline using H2O as the hydrogen source with 80%Faradaic efficiency and the reverse dehydrogenation of hydrogen-rich 1,2,3,4-tetrahydroquinoxaline with up to 99%yield and selectivity.The in situ generated active hydrogen atom(H^(*))is plausibly involved in the hydrogenation of quinoxaline,where a consecutive hydrogen radical coupled electron transfer pathway is proposed.Notably,the MoNi_(4)alloy exhibits efficient quinoxaline hydrogenation at an overpotential of only 50 mV,owing to its superior water dissociation ability to provide H^(*)in alkaline media.In situ Raman tests indicate that the Ni^(Ⅱ)/Ni^(Ⅲ)redox couple can promote the dehydrogenation process,representing a promising anodic alternative to low-value oxygen evolution.Impressively,electrocatalytic deuteration is easily achieved with up to 99%deuteration ratios using D2O.This method is capable of producing a series of functionalized hydrogenated and deuterated quinoxalines. 展开更多
关键词 Electrocatalysis Transfer hydrogenation DEUTERATION Water as the hydrogen source Bifunctional electrode
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Amorphous CoOx coupled carbon dots as a spongy porous bifunctional catalyst for efficient photocatalytic water oxidation and CO2 reduction 被引量:4
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作者 Wanjun Sun Xiangyu Meng +5 位作者 Chunjiang Xu Junyi Yang Xiangming Liang Yinjuan Dong Congzhao Dong Yong Ding 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2020年第12期1826-1836,共11页
Cobalt-based oxides,with high abundance,good stability and excellent catalytic performance,are regarded as promising photocatalysts for artificial photosynthetic systems to alleviate foreseeable energy shortages and g... Cobalt-based oxides,with high abundance,good stability and excellent catalytic performance,are regarded as promising photocatalysts for artificial photosynthetic systems to alleviate foreseeable energy shortages and global warming.Herein,for the first time,a series of novel spongy porous CDs@CoOx materials were synthesized to act as an efficient and stable bifunctional photocatalyst for water oxidation and CO2 reduction.Notably,the preparation temperatures visibly influence the morphologies and photocatalytic performances of the CDs@CoOx.Under the optimal conditions,a maximum O2 yield of 40.4% and pretty apparent quantum efficiency(AQE)of 58.6% at 460 nm were obtained over CDs@CoOx-300 for water oxidation.Similarly,the optimized sample CDs@CoOx-300 manifests significant enhancement on the CO2-to-CO conversion with a high selectivity of 89.3% and CO generation rate of 8.1μmol/h,which is superior to most previous cobalt-based catalysts for CO2 reduction.The composite CDs@CoOx-300 not only exposes more active sites but also facilitates electron transport,which results in excellent photocatalytic activity.In addition,the boosted photocatalytic behavior is attributed to the synergistic effect between CoOx and CDs,which was verified by the photocatalytic activity control experiments and electrochemical characterization.The work offers a novel strategy to fabricate a high performance bifunctional photocatalyst for water oxidation and CO2 reduction. 展开更多
关键词 Carbon dots coupled CoOx Bifunctional photocatalyst Water oxidation CO2 reduction Synergistic effect
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Acid‐promoted Ir‐La‐S/AC‐catalyzed methanol carbonylation on single atomic active sites 被引量:3
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作者 Zhou Ren Yuan Lyu +2 位作者 Siquan Feng Xiangen Song Yunjie Ding 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第6期1060-1069,共10页
Highly active Ir‐La‐S/AC catalyst was successfully prepared by co‐impregnation of an activated carbon(AC) carrier with a sulfuric acid solution of Ir and La species and compared with a tradition‐ally prepared Ir... Highly active Ir‐La‐S/AC catalyst was successfully prepared by co‐impregnation of an activated carbon(AC) carrier with a sulfuric acid solution of Ir and La species and compared with a tradition‐ally prepared Ir‐La/AC catalyst. High angle annular dark‐field‐scanning transmission electron mi‐croscopy(HAADF‐STEM) measurement results show that most of the Ir species on Ir‐La‐S/AC exist as single atomic sites, while those on Ir‐La/AC exist as nanoparticles with an average diameter of 1.5 nm. Evaluation of Ir‐La‐S/AC as a catalyst for heterogeneous carbonylation of methanol to acetyl gave a maximum TOF (turn‐over‐frequency) of 2760 h^–1, which was distinctly higher than that achieved by the Ir‐La/AC catalyst(approximately 1000 h^-1). Temperature‐programmed desorption of ammonia(NH3‐TPD) result shows that the addition of sulfuric acid during the preparation pro‐cedure results in significantly more acidic sites on Ir‐La‐S/AC than those on Ir‐La/AC, which plays a key role in the enhancement of CO insertion as the rate‐determining step. Tempera‐ture‐programmed reduction(TPR) and in situ X‐ray photoelectron spectroscopy reveal that Ir spe‐cies are more reducible, and that more Ir^+ might be formed by activation of Ir‐La‐S/AC than those on the Ir‐La/AC catalyst, which is thought to be beneficial for reductive elimination of AcI from Ir^3+ species as an essential step for CH3I regeneration and acetyl formation. 展开更多
关键词 Heterogeneous METHANOL carbonylationIr‐La‐S/ACcatalyst BIFUNCTIONAL catalyst Single‐atomic active site Co‐impregnation
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Surface coupling of methyl radicals for efficient low‐temperature oxidative coupling of methane 被引量:3
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作者 Shihui Zou Zhinian Li +12 位作者 Qiuyue Zhou Yang Pan Wentao Yuan Lei He Shenliang Wang Wu Wen Juanjuan Liu Yong Wang Yonghua Du Jiuzhong Yang Liping Xiao Hisayoshi Kobayashi Jie Fan 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2021年第7期1117-1125,共9页
Selective coupling of methyl radicals to produce C_(2) species(C2H4 and C2H6)is a key challenge for oxidative coupling of methane(OCM).In traditional OCM reaction systems,homogeneous transformation of methyl radicals ... Selective coupling of methyl radicals to produce C_(2) species(C2H4 and C2H6)is a key challenge for oxidative coupling of methane(OCM).In traditional OCM reaction systems,homogeneous transformation of methyl radicals in O_(2)‐containing gases are uncontrollable,resulting in limited C_(2) selectivity and yield.Herein,we demonstrate that methyl radicals generated by La_(2)O_(3)at low reaction temperature can selectively couple on the surface of 5 wt%Na2WO4/SiO_(2).The controllable surface coupling against overoxidation barely changes the activity of La_(2)O_(3)but boosts the C_(2)selectivity by three times and achieves a C_(2)yield as high as 10.9%at bed temperature of only 570℃.Structure‐property studies suggest that Na_(2)WO_(4) nanoclusters are the active sites for methyl radical coupling.The strong CH_(3)·affinity of these sites can even endow some methane combustion catalysts with OCM activity.The findings of the surface coupling of methyl radicals open a new direction to develop OCM catalyst.The bifunctional OCM catalyst system,which composes of a methane activation center and a CH_(3)·coupling center,may deliver promising OCM performance at reaction temperatures below the ignition temperature of C2H6 and C2H4(~600℃)and is therefore more controllable,safer,and certainly more attractive as an actual process. 展开更多
关键词 Oxidative coupling of methane Bifunctional catalysis Methyl radicals Surface coupling La_(2)O_(3) Na_(2)WO_(4)/SiO_(2)
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Three-dimensional lily-like CoNi_2S_4 as an advanced bifunctional electrocatalyst for hydrogen and oxygen evolution reaction 被引量:4
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作者 Jingwei Li Qiuna Zhuang +3 位作者 Peiman Xu Dawei Zhang Licheng Wei Dingsheng Yuan 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第8期1403-1410,共8页
Designing low-cost, highly efficient, and stable bifunctional electrocatalysts for both hydrogen evolution reaction(HER) and oxygen evolution reaction(OER) is of vital significance for water splitting.Herein, thre... Designing low-cost, highly efficient, and stable bifunctional electrocatalysts for both hydrogen evolution reaction(HER) and oxygen evolution reaction(OER) is of vital significance for water splitting.Herein, three-dimensional lily-like CoNi_2S_4 supported on nickel foam(CoNi_2S_4/Ni) has been fabricated by sulfuration of the Co–Ni precursor. As expected, CoNi_2S_4/Ni possesses such outstanding electrocatalytic properties that it requires an overpotential of only 54 mV at 10 mA cm^(-2) and 328 mV at 100 mA cm^(-2) for HER and OER, respectively. Furthermore, by utilizing the CoNi_2S_4/Ni electrodes as bifunctional electrocatalysts for overall water splitting, a current density of 10 mA cm^(-2) can be obtained at a voltage of only 1.56 V. 展开更多
关键词 Bifunctional electrocataly stHydrogen evolution reaction Oxygen evolutionreaction Lily‐likeCoNi2S4 Overall water splitting
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Two-in-one strategy to construct bifunctional oxygen electrocatalysts for rechargeable Zn-air battery 被引量:2
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作者 Huibing Liu Rixin Xie +4 位作者 Ziqiang Niu Qiaohuan Jia Liu Yang Shitao Wang Dapeng Cao 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第11期2906-2912,共7页
Integrating two different catalytic active sites into one composite is a useful 2-in-1 strategy for designing high-efficient bifunctional catalysts,which can easily tailor the activity of each reaction.Hence,we adopt ... Integrating two different catalytic active sites into one composite is a useful 2-in-1 strategy for designing high-efficient bifunctional catalysts,which can easily tailor the activity of each reaction.Hence,we adopt the 2-in-1 strategy to design the metal oxyhydroxide supported on N-doped porous carbons(PA-CoFe@NPC)as the oxygen bifunctional catalyst,where NPC provides the activity for oxygen reduction reaction(ORR)while the metal oxyhydroxide is responsible for oxygen evolution reaction(OER).Results demonstrate that the PA-CoFe@NPC indeed exhibits both super ORR and OER activities.Impressively,using bifunctional PA-CoFe@NPC as the oxygen electrode,the resulting Zn-air battery exhibits outstanding charge and discharge performance with the peak power density of 156.3 mW cm^(-2),and also exhibits a long-term cycle stability with continuous cyclic charge and discharge of 170 hours that is obviously better than the 20%Pt/C+IrO_(2)based one.The 2-in-1 strategy in this work can be efficiently extended to design other bi-or multi-functional electrocatalysts. 展开更多
关键词 Two-in-one strategy Bifunctional catalyst Oxygen reduction Oxygen evolution Zn-air battery
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Sea urchin‐like NiMoO_(4) nanorod arrays as highly efficient bifunctional catalysts for electrocatalytic/photovoltage‐driven urea electrolysis 被引量:2
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作者 Chenxin Chen Suqi He +3 位作者 Kamran Dastafkan Zehua Zou Qingxiang Wang Chuan Zhao 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第5期1267-1276,共10页
Developing multifunctional electrocatalysts with high catalytic activity,longterm stability,and low cost is essential for electrocatalytic energy conversion.Herein,sea urchinlike NiMoO_(4) nanorod arrays grown on nick... Developing multifunctional electrocatalysts with high catalytic activity,longterm stability,and low cost is essential for electrocatalytic energy conversion.Herein,sea urchinlike NiMoO_(4) nanorod arrays grown on nickel foam has been developed as a bifunctional electrocatalyst for urea oxidation and hydrogen evolution.The NiMoO_(4)‐200/NF catalyst exhibits efficient activity toward hydrogen evolution reaction with a low overpotential of only 68 mV in 1.0 mol/L KOH to gain a current density of 10 mA cm^(–2).The NiMoO_(4)‐300/NF catalyst exhibits a prominent oxygen evolution reaction(OER)catalytic activity with an overpotential of 288 mV at 50 mA cm^(–2),as well as for urea oxidation reaction with an ultralow potential of 1.36 V at 10 mA cm^(–2).The observed difference in electrocatalytic activity and selectivity,derived by temperature variation,is ascribed to different lattice oxygen contents.The lattice oxygen of NiMoO_(4)‐300/NF is more than that of NiMoO_(4)‐200/NF,and the lattice oxygen is conducive to the progress of OER.A urea electrolyzer was assembled with Ni‐MoO_(4)‐200/NF and NiMoO_(4)‐300/NF as cathode and anode respectively,delivering a current density of 10 mA cm^(–2)at a cell voltage of merely 1.38 V.The NiMoO_(4)nanorod arrays has also been successfully applied for photovoltage‐driven urea electrolysis and hydrogen production,revealing its great potential for solar‐driven energy conversion. 展开更多
关键词 NiMoO4 nanorod Bifunctional electrocatalyst Urea electrolysis Photovoltage‐driven Lattice oxygen Sea urchin‐like
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Toluene methylation with syngas to para‐xylene by bifunctional ZnZrO_(x)‐HZSM‐5 catalysts 被引量:2
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作者 Xiaoqin Han Jiachang Zuo +1 位作者 Danlu Wen Youzhu Yuan 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第4期1156-1164,共9页
Toluene methylation with methanol on H‐ZSM‐5(Z5)zeolite for the directional transformation of toluene to xylene has been industrialized.However,great challenges remain because of the high energy barrier of methanol ... Toluene methylation with methanol on H‐ZSM‐5(Z5)zeolite for the directional transformation of toluene to xylene has been industrialized.However,great challenges remain because of the high energy barrier of methanol deprotonation to the methoxy group,the side reaction of methanol to olefins,coke formation,and the deactivation of zeolites.Herein,we report the toluene methylation coupled with CO hydrogenation to showcase an enhancement in para‐xylene(PX)selectivity by employing a bifunctional catalyst composed of ZnZrO_(x)(ZZO)and modified Z5.The results showed that a PX selectivity of up to 81.8%in xylene and xylene selectivity of 64.8%in hydrocarbons at 10.3%toluene conversion can be realized over the bifunctional catalyst on a fixed‐bed reactor.The selectivity of gaseous hydrocarbons decreased to 10.9%,and approximately half of that was observed in methanol reagent route where the PX selectivity in xylene was 38.8%.We observed that the acid strength,the quantity ratio of Brönsted and Lewis acid sites,and the pore size of zeolites were essential for the PX selectivity.The investigation of the H_(2)/D_(2) kinetic isotope effect revealed that the newborn methyl group in xylene resulted from the hydrogenation of CO rather than toluene disproportionation.Furthermore,the catalyst showed no evident deactivation within the 100 h stability test.The findings offer a promising route for the production of value‐added PX with high selectivity via toluene methylation coupled with syngas conversion. 展开更多
关键词 Toluene methylation Syngas conversion Para‐xylene Bifunctional catalyst ZnZrO_(x)‐ZSM‐5
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Bifunctional TiO2 Catalysts for Efficient Cr(VI) Photoreduction Under Solar Light Irradiation Without Addition of Acids 被引量:2
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作者 Fu-cheng Shi Wen-dong Wang Wei-xin Huang 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2012年第2期214-218,I0004,共6页
Bifunctional TiO2 photocatalysts co-doped with nitrogen and sulfur were prepared by the controlled thermal decomposition of ammonium titanyl sulfate precursor. They have both photocatalytic activity and Brφnsted acid... Bifunctional TiO2 photocatalysts co-doped with nitrogen and sulfur were prepared by the controlled thermal decomposition of ammonium titanyl sulfate precursor. They have both photocatalytic activity and Brφnsted acidity, and thus are active in the photoreduction of Cr(VI) under solar light irradiation without the addition of acids. The activity is superior to that of Degussa P25 in the acidified suspension at the same pH adjusted by H2SO4. 展开更多
关键词 Cr(VI) photocatalytic reduction TIO2 Brcnsted acidity Bifunctional catalyst
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