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Insight into the mechanism of 5-hydroxymethylfurfural electroreduction to 2,5-bis(hydroxymethyl)furan over Cu anchored N-doped carbon nanosheets

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Nano Research 2024年第9期17卷 7991-7999页

作者： Haoran Wu Xinwei Chen Haishan Xu Runlu Yang Xin Wang Junying Chen zhenbing xie Liang Wu Yiyong Mai School of Chemical Engineering Zhengzhou UniversityZhengzhou 450001China School of Chemistry and Chemical Engineering Frontiers Science Center for Transformative MoleculesShanghai Key Laboratory of Electrical Insulation and Thermal AgeingShanghai Jiao Tong UniversityShanghai 200240China Department of Chemistry Tangshan Normal UniversityTangshan 063000China

Design of non-noble metal electrocatalysts for biomass conversion to high-value chemicals and understanding the related catalytic mechanisms are of profound significance but have remained a major ***,we developed a novel biomass-derived electrocatalyst(denoted as Cu/NC),featuring with electron-deficient copper nanoparticles anchored on N-doped carbon nanosheets,for the electrochemical reduction of 5-hydroxymethylfurfural(HMF)to 2,5-bis(hydroxymethyl)furan(BHMF,a vital precursor of functional polymers).The optimized Cu/NC electrocatalyst exhibited an excellent performance with high Faradaic efficiency(89.5%)and selectivity(90.8%)of BHMF at a low concentration of HMF(18.1 mM).Even at a very high HMF concentration(108.6 mM),the Faraday efficiency and selectivity of BHMF could still reach 74.8%and 81.1%,*** performance approached those of the reported noble metal-based *** study revealed that the N doping in the Cu/NC catalyst could regulate the electronic structure of Cu,strengthening the adsorption of the HMF carbonyl group,and thus boosting the selectivity of ***,strong electronic metal-support interactions of Cu and the N-doped carbon support optimized the charge transfer rate,thus promoting the dissociation of water to the active hydrogen(H^(*))species and boosting the reaction kinetic rate of H^(*)and HMF.

关键词： biomass 5-hydroxymethylfurfural electrochemical reduction N-doped carbon materials 2,5-bis(hydroxymethyl)furan

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中职农科类专业人才培养模式创新探究

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创新创业理论研究与实践 2019年第6期2卷 108-109页

作者：谢振兵金玉斌河北省张北县职教中心

中等职业学校农科类专业应'对口高考'而开设,应'对口高考'而教,以'课堂为中心'的普高式人才培养模式已经远远不能适应当前新形势发展的需要。新常态下我国农村城镇化发展必然由传统农村向现代农村变迁,必然由传统农业向现代农业转变,也... 详细信息

中等职业学校农科类专业应'对口高考'而开设,应'对口高考'而教,以'课堂为中心'的普高式人才培养模式已经远远不能适应当前新形势发展的需要。新常态下我国农村城镇化发展必然由传统农村向现代农村变迁,必然由传统农业向现代农业转变,也必将使传统农民向现代农民转化。因此,创新中职农科类专业人才培养模式,是时代发展的要求,是农业现代化、农村城镇化发展的要求,更是新型职业农民培育的必然要求。

关键词：中职农科类专业人才培养模式转型

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燃料电池发动机测试评价体系

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时代汽车 2023年第5期 88-90页

作者：孙田陈光杨沄芃王祥祥谢振兵中国汽车技术研究中心有限公司天津市300300 中汽研新能源汽车检验中心(天津)有限公司天津市300300

燃料电池示范应用政策的开展,对于推动氢燃料电池汽车的快速发展、提升燃料电池行业信息具有积极意义。燃料电池发动机作为燃料电池汽车的动力核心,直接影响燃料电池汽车的输出性能,因此对于燃料电池发动机的测试至为重要,本文对目前行... 详细信息

燃料电池示范应用政策的开展,对于推动氢燃料电池汽车的快速发展、提升燃料电池行业信息具有积极意义。燃料电池发动机作为燃料电池汽车的动力核心,直接影响燃料电池汽车的输出性能,因此对于燃料电池发动机的测试至为重要,本文对目前行业内对于燃料电池发动机的测试方法和评价体系进行汇总及介绍,供燃料电池行业参考。

关键词：燃料电池发动机测试指标评价方法

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Experimental and numerical investigation on opposing plasma synthetic jet for drag reduction

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Chinese Journal of Aeronautics 2022年第8期35卷 75-91页

作者： Wei xie zhenbing LUO Yan ZHOU Wenqiang PENG Qiang LIU Dengpan WANG College of Aerospace Engineering National University of Defense TechnologyChangsha 410073China Beijing Special Engineering Design and Research Institute Beijing 100000China

Experimental and numerical studies are carried out to validate the potential of opposing Plasma Synthetic Jet(PSJ)for drag reduction for a ***,flow field changes of opposing PSJ are analyzed by comparing the experimental schlieren images and simulation results in a supersonic free stream of Mach number *** PSJ is a kind of unsteady pulsed jet,the shock standoff distance increases initially and then decreases under the control of PSJ,which corresponds to the change of the strength of ***,the amount of drag reduction of the hemisphere increases initially and then *** is found that there is a short period of“drag rise”during the formation of PSJ before the drag reduction,which is induced by the generation of normal shock waves and the area difference of the cavity wall of PSJ Actuator(PSJA).Secondly,the effects of five parameters,including exit diameter,discharge energy of PSJA,Mach number,static pressure of incoming flow and angle of attack,on drag reduction of opposing PSJ were studied in detail by using numerical *** is found that the Maximum Pressure Ratio(MPR)has a significant impact on the average drag reduction for a configuration-determined *** the configuration selected in this study,the flow field of opposing PSJ shows typical Short Penetration Mode(SPM)in a control cycle of PSJ when the MPR is less than ***,the flow field shows typical Long Penetration Mode(LPM)at some time when the MPR is bigger than *** better drag reduction is achieved in this case.

关键词： Drag reduction Opposing jet Parameter study Plasma synthetic jet(PSJ) Supersonic flow

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Large eddy simulation study on drag reduction performance of array-based plasma synthetic jet actuators

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Chinese Journal of Aeronautics 2024年第10期37卷 118-135页

作者： Yunan WANG zhenbing LUO Wei xie Yan ZHOU Qiang LIU Wenqiang PENG Yinxin ZHU College of Aerospace Science and Engineering National University of Defense TechnologyChangsha 410073China

Large Eddy Simulation(LES)is first used to investigate the drag reduction effect of an array-based configuration of Plasma Synthetic Jet Actuators(PSJAs)on a hemisphere in supersonic inflow,and analyze the effect of energy allocation and array angle on the drag reduction performance of opposing Plasma Synthetic Jet(PSJ)in this *** simulation results have been compared with experimental data,confirming the validity of the simulation *** results show that different energy allocations have a significant effect on the drag of the ***,the effect of the change in array angle on the drag of the hemisphere is not as noticeable as the effect caused by energy *** regions between the two PSJAs occur,which undermine the effectiveness of drag *** Turbulent Kinetic Energy(TKE)regions primarily concentrate on the core region of the jet and downstream of the bow *** influence of the array angle on TKE is most evident in the downstream region of the exits of the PSJs on both *** evolution of the coherent structures reveals that as the PSJ intensity decreases,the largescale vortices progressively break up into smaller-scale vortices,and energy is also transferred from large-scale structures to small-scale structures.

关键词： Plasma synthetic jet Shock wave Large eddy simulation Drag reduction Flow control

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Trailing-edge shock loss control with self-sustaining synthetic jet in a supersonic compressor cascade

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Chinese Journal of Aeronautics 2023年第7期36卷 366-377页

作者： Yinxin ZHU Wenqiang PENG zhenbing LUO Qiang LIU Wei xie Pan CHENG Yan ZHOU College of Aerospace Science and Engineering National University of Defense TechnologyChangsha 410073China

To effectively reduce the loss of strong shock wave at the trailing edge of the supersonic cascade under high backpressure,a shock wave control method based on self-sustaining synthetic jet was *** self-sustaining synthetic jet was applied on the pressure side of the blade with the blow slot and the bleed slot arranged upstream and downstream of the trailing-edge shock,*** flow control mechanism and effects of parameters were investigated by numerical *** results show that the self-sustaining synthetic jet forms an oblique shock wave in the cascade passage which slows down and pressurizes the airflow,and the expansion wave downstream of the blow slot weakens the shock strength which can effectively change the Mach reflection to regular reflection and thus weaken the shock *** the suction effect can reduce loss near blade *** with the baseline cascade,the self-sustaining jet actuator can reduce flow losses by 6.73%with proper location design and vibration of diaphragm.

关键词： Compressors Flow control Mach reflection Trailing-edge shock Self-sustaining synthetic jet Shock waves Supersonic cascades

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Experimental study on shock interaction control of double wedge in high-enthalpy hypersonic flow subject to plasma synthetic jet

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Chinese Journal of Aeronautics 2024年第4期37卷 151-165页

作者： Xuzhen xie Qiang LIU Yan ZHOU zhenbing LUO Wei xie Guanghui BAI Kai LUO Qiu WANG Jianjun WU College of Aerospace Science and Engineering National University of Defense TechnologyChangsha 410073China China Academy of Launch Vehicle Technology Beijing 100076China Institute of Mechanics Chinese Academy of SciencesBeijing 100190China

The hypersonic shock-shock interaction flow field at double-wedge geometries controlled by plasma synthetic jet actuator is experimentally studied in a Ma = 8 high-enthalpy shock tunnel with the purpose of exploring a novel technique for reducing surface heat flux in a real flight environment. The results demonstrate that increasing the discharge energy is advantageous in eliminating the shock wave, shifting the shock wave interaction point, and shortening the control response time. The oblique shock wave can be completely removed when the actuator's discharge energy grows from 0.4 J to 11.5 J, and the displacement of the shock wave interaction point increases by 124.56%, while the controlled response time is shortened by 30 μs. Besides, the reduction in diameter of the jet exit is firstly proved to have a negative impact on energy deposition in a working environment with incoming flow, which reduces the discharge energy and hence decreases the control effect. The shock wave control response time lengthens when the jet exits away from the second wedge. Along with comparing the change in wall heat flux at the second wedge over time, the control effect of plasma synthetic jet actuator with and without inflation is also analyzed. When plasma synthetic jet works in inflatable mode, both the ability to eliminate shock waves and the shifting effect of the shock wave interaction point are increased significantly, and the wall heat flux is also reduced.

关键词： Hypersonic flow High-enthalpy flow Plasma synthetic jet Shock wave Flow control

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On the drag reduction mechanism of hypersonic turbulent boundary layers subject to heated wall blowing

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Advances in Aerodynamics 2023年第1期5卷 126-148页

作者： Qiang Liu zhenbing Luo Yan Zhou Wei xie Siwei Dong College of Aerospace Science and Engineering National University of Defense TechnologyChangsha 410073China State Key Laboratory of Aerodynamics Mianyang 621000China

Turbulence drag reduction is of great significance for the range increase of hypersonic flight *** proposed velocity-temperature coupling control method(Liu et al,Phys Rev Fluids 6:044603,2021)is further extended to the hypersonic turbulent boundary *** numerical simulation results of four comparative cases show that the heated wall blowing achieves a drag reduction rate of 10.58%,which is about the sum of wall blowing(5.27%)and wall heating(6.35%).By evaluating the control efficiency,however,it is found that heated wall blowing is not as good as wall blowing and cannot obtain net energy saving *** modified FIK decompositions of skin friction coefficient indicate that the cliffy decrease of the mean convection term is the primary contribution for the drag *** of the proposed control measure on turbu-lence statistics and coherent structures are also *** vortex is found to be away from the wall,thus leading to a lower friction drag.

关键词： Hypersonic turbulent boundary layer Turbulence drag reduction Velocity-temperature coupled control Turbulence statistics Turbulence structures Direct numerical simulations

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Deformation features of garnet-bearing granites from Huwan,western Dabie Mountains

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Science China Earth Sciences 2009年第1期52卷 55-65页

作者： YANG KunGuang LIU Qiang xie JianLei DAN Wei SHE zhenbing MA ChangQian Key Laboratory of Tectonic and Petroleum Resources Ministry of EducationChina University of GeosciencesWuhan 430074China Faculty of Earth Sciences China University of GeosciencesWuhan 430074China

Foliated garnet-bearing granite,usually associated with high pressure and ultrahigh-pressure(UHP) metamophic rocks,is a particular rock-type extensively exposed in the Mesozoic Dabie-Sulu orogenic belt of *** study focuses on deformation features and SHRIMP zircon dating of foliated garnet granite in a high-pressure metamorphic unit from Huwan,western Dabie Mountains in order to resolve discrepancies in current versions of its petrogenesis and structural *** dating reveals a zircon age of 762 ± 15 Ma(MSWD=1.7) for Huwan granites,representing the Middle to Late Neoproterozoic age of intrusion and *** and microstructural studies show that the Huwan granite body underwent multiple-stage *** deformation was manifested by an early stage of rootless folding and imposition of relict foliation(S1);an Indosinian main stage marked by imposition of north-dipping penetrative gneissosity(S2) and development of ductile shear zones under NNE-SSW directed compression;and a final Indosinian stage of southward thrusting of the Huwan high-pressure *** level extension prevailed after the Late Triassic,giving rise to south-dipping thrust faults and north-dipping normal faults.

关键词： SHRIMP dating structural analysis foliated garnet granites Huwan Dabie orogen

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The Termination and Aftermath of the Lomagundi -Jatuli Carbon Isotope Excursions in the Paleoproterozoic Hutuo Group, North China

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Journal of Earth Science 2016年第2期27卷 297-316页

作者： zhenbing She Fanyan Yang Wei Liu Luhua xie Yusheng Wan Chao Li Dominic Papineau State Key Laboratory of Biogeology and Environmental Geology China University of Geosciences Wuhan 430074 China School of Earth Sciences China University of Geosciences Wuhan 430074 China Ningxia Geology And Mineral Resources Centre Lab Yinchuan 750021 China Tianjin Research Institute for Water Transport Engineering M. O. T. Tianjin 300456 China State Key Laboratory of Isotope Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China Key Laboratory of Marginal Sea Geology Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China Beijing SHRIMP Center Institute of Geology Chinese Academy of Geological Sciences Beijing 100037 China London Centre for Nanotechnology University College London London Department of Earth Sciences University College London 17-19 Gower Street London United Kingdom

The Lomagundi-Jatuli Event（LJE） is one of the largest and earliest positive carbon isotope excursions preserving δ^（13）C_（carb） values between ＋5 and ＋16‰ in Paleoproterozoic carbonates worldwide. However, the duration, amplitude and patterns of these excursions remain poorly constrained. The 2.14-1.83 Ga Hutuo Group in the North China Craton is a 〉10 km thick volcano-sedimentary sequence, including 〉5 km thick well-preserved carbonates that were deposited in supra-tidal to sub-tidal environments. C-O isotopic and elemental analyses of 152 least altered samples of the carbonates revealed a three-stage δ^（13）C evolution. It began with an exclusively positive δ^（13）C_（carb）（＋1.3 to ＋ 3.4‰） stage in the ~2.1 Ga carbonate in the Dashiling and Qingshicun Formations, followed by a transition from positive values to oscillating positive and negative values in ~3 000 m thick carbonates of the Wenshan, Hebiancun, Jianancun, and Daguandong Formations, and end with exclusively negative δ^（13）C_（carb） values preserved in 〉 500 m thick dolostones of the Huaiyincun and Beidaxing Formations. It appears that much of the LJE, particularly those extremely positive δ^（13）C_（carb） signals, was not recorded in the Hutuo carbonates. The exclusively positive δ^（13）C_（carb） values（＋1.3 to ＋ 3.4‰） preserved in the lower formations likely correspond to the end of the LJE, whereas the subsequent two stages reflect the aftermath of the LJE and the onset of Shunga-Francevillian event（SFE）. The present data point to an increased influence of oxygen on the carbon cycle from the Doucun to the Dongye Subgroups and demonstrate that the termination of the LJE in the North China Craton is nearly simultaneous with those in Fennoscandia and South Africa.

关键词： Paleoproterozoic Lomagundi-Jatuli event Hutuo Group carbon isotope carbonate.

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