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Ca2+ cation-mediated microenvironment for electrochemical hydrodimerization of furfural

Science china Chemistry 2025年

作者： Wei Du Shuangshuang cha.Can Lei Mengxin Qu Zhongqiang Deng Ming Gong Xinhe Bao Department of Chemistry and Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Fudan University State Key Laboratory of Catalysis National Laboratory for Clean Energy Collaborative Innovation Center of Chemistry for Energy Materials Dalian Institute of Chemical Physics Chinese Academy of Sciences

Furfural is one of the most important biomass-based platform molecules as sustainable precursors for chemicals and fuels. The electrochemical hydrodimerization of furfural can generate hydrofuroin, which is a promising precursor for gasoline or jet ***, steering the selectivity toward hydrodimerization under near-neutral conditions that suppress polymerization and disproportionation of furfural remains cha.lenging. Herein, we discovered that tuning the electrolyte cations could be an effective and alternative strategy for modulating furfural reduction to the traditional electrocatalyst design. Under the optimal Ca2+cations,hydrofuroin yield could be much improved from other cations with hydrofuroin selectivity of 95.5%. The systematic cha.acterization of the ion-centered double layer reflected the suitable sizes and cha.ges of hydrated Ca2+for suppressing the hydrogen evolution reaction from activation of surrounding water molecules as well as encouraging furfural accumulation via non-covalent interaction for directing the electron transfer to furfurals. Ions with smaller or larger sizes can either activate local water molecules or form a crowded ionic interface that casts an adverse effect on furfural enrichment. This work not only presents an effective strategy for facilitating biomass valorization via hydrodimerization but also emphasizes the essential role of the ion-centered microenvironment for steering the electrocatalytic pathways.

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Conception and Design of Active Balancer for Planar Mecha.isms

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chinese Journal of Mecha.ical Engineering 2009年第6期22卷 822-832页

作者： ZHANG ying YAO Yan-An cha.Jianzhong School of Mecha.ical and Electronic Control Engineering Beijing Jiaotong University Beijing 100044 China

The dynamic balancing is an important issue in mecha.ism design. For the existing balancing methods, both passive and active ones, there is still room for improvement in adaplability and independency. In view of this, a concept of active balancer is developed as a new solution for the dynamic balancing with more flexibility. The proposed balancer is an independent additional device with a control system inside, which consists of a two-degree-of-freedom （DOF） linkage and a controllable motor, and can be attached to a machine expediently with little cha.ge to its original structure and motion. One of the two inputs of the two-DOF linkage shares the same shaft with its output, which is connected to the input shaft of a machine to be balanced and driven by the original actuator. The other input is driven by the control motor. By properly selecting the speed trajectories of the control motor and link parameters of the two-DOF linkage, one or more dynamic effects of the mecha.isms can be minimized or eliminated adaptively. The design procedure of the active balancer is put forward and a two-step optimization is developed to find out optimal design parameters of the balancer for various design requirements and constraints. Taking a force-balanced crank-rocker mecha.ism as the reference mecha.ism, numerical examples are given to illustrate the design procedure. The balancing effects of the proposed balancer are compared with those of the existing adding dyads （DYAD） method. The results show that the introduction of the control system provides the active balancer with better balancing effect and more flexibility than the DYAD method. A considerable reduction in the dynamic effects （input torque, shaking moment and shaking force） can be achieved for different balancing object by designing the structural and control parameters of the balancer, and the deterioration of dynamic performance caused by alterative working conditions can be compensated effectively by redesigning the

关键词： active balancing shaking moment input torque shaking force optimum balancing two-degree-of-freedom linkage

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根据孢粉资料推论长江三角洲地区1200年以来的环境变迁

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古生物学报 1996年第2期35卷 136-154页

作者：刘金陵 cha.,WYB 中国科学院南京地质占生物研究所

根据长江三角洲地区全新世９个具代表性钻孔的孢粉分析结果讨论了本区约自１２０００年以来的环境变迁。孢粉序列表明：本区约在距今１２０００年前就已发育了亚热带性质的落叶常绿阔叶林，约在９０００—５０００ａＢ．Ｐ．常绿阔叶林... 详细信息

根据长江三角洲地区全新世９个具代表性钻孔的孢粉分析结果讨论了本区约自１２０００年以来的环境变迁。孢粉序列表明：本区约在距今１２０００年前就已发育了亚热带性质的落叶常绿阔叶林，约在９０００—５０００ａＢ．Ｐ．常绿阔叶林获得大发展。孢粉序列良好地记录了古季风盛衰的历史，表现在：１２０００—１０８００ａＢ．Ｐ．较温湿，东南季风强度加强；１０８００（或１１０００－１００００（或１０３００）ａＢ．Ｐ．偏闵干，东南季风强度减弱，对应于新仙女木期；约自１００００ａ．Ｐ．起，气候好转，气温明显上升，东南季风强度再次增强，约在９０００—５０００ａＢ．Ｐ．温暖湿润，为东南季风强盛期。此外．还讨论了约在距今１１０００年前的海侵，全新世下限和哥德堡事件的年代问题，并确定哥德堡事件的年限为１１０００—１０００ａＢ。Ｐ。

关键词：古生物生态学长江三角洲环境变迁古植被孢粉

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11000年以来太湖的形成与演变

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古生物学报 1996年第2期35卷 129-135页

作者： cha.,WYB 刘金陵中国科学院南京地质古生物研究所

１１０００年以来太湖的形成与演变ＷｉｌｌｉａｍＹ．Ｂ．Ｃｈａｎｇ（ＣｅｎｔｅｒｆｏｒＧｒｅａｔＬａｋｅｓａｎｄＡｑｕａｔｉｃＳｃｉｅｎｃｅａｎｄＳｃｈｏｏｌｏｆＮａｔｕｒａｌＲｅｓｏｕｒｃｅｓａｎｄＥｎｖｉｒｏｎｍｅ... 详细信息

１１０００年以来太湖的形成与演变ＷｉｌｌｉａｍＹ．Ｂ．Ｃｈａｎｇ（ＣｅｎｔｅｒｆｏｒＧｒｅａｔＬａｋｅｓａｎｄＡｑｕａｔｉｃＳｃｉｅｎｃｅａｎｄＳｃｈｏｏｌｏｆＮａｔｕｒａｌＲｅｓｏｕｒｃｅｓａｎｄＥｎｖｉｒｏｎｍｅｎｔ，ｔｈｅＵｎｉｖｅｒｓｉｔｙｏ...

关键词：太湖形成演变中国古地理学

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长江二角洲气侯极端事件的预测及其与填尔尼诺和南方涛动(ENSO)的关系

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古生物学报 1996年第2期35卷 199-212页

作者： cha.,WYB 陈韵竹台湾台南县归仁乡长荣管理学院

通过研究长江三角洲近５００年来的气候历史记录，揭示了这种气候极端事件出现的规律、模式，及其与全球气候变迁的关系。在过去５００年中（自公元１５００年以来），共出现了１６个区域性气候极端事件。所有这些事件都与所报道的埃尔... 详细信息

通过研究长江三角洲近５００年来的气候历史记录，揭示了这种气候极端事件出现的规律、模式，及其与全球气候变迁的关系。在过去５００年中（自公元１５００年以来），共出现了１６个区域性气候极端事件。所有这些事件都与所报道的埃尔尼诺和南方涛动（ＥＮＳＯ）事件有关。研究表明，本区降雨量大的年际变化都出现在ＥＮＳＯ事件之中或之后。因此长江三角洲这种受人类影响日益增强的系统管理，必须考虑到这种主要气候变化的周期、强度，以及因人口的增长和社会机构的改变对气候造成的影响。

关键词：气候学极端气候事件长江三角洲 ENSO

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Fabrication of Nb2O5/C nanocomposites as a high performance anode for lithium ion battery

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chinese Chemical Letters 2017年第4期28卷 755-758页

作者： Gan-ying Zeng Hao Wang Jing Guo Li-Mei cha.Yu-Hai Dou Jian-Min Ma Schcool of Physics and Electronics Hunan University Changsha 410082 China College of Materials Science and Engineering Hunan University Changsha 410082 China Institute for Superconducting and Electronic Materials Australian Institute for Innovative Materials University of Wollongong Wollongong New South Wales 2500 Australia Science and Technology on Surface Physics and Chemistry Laboratory China Academy of Engineering Physics Mianyang 621908 China

Nb_2O_5/C nanosheets are successfully prepared through a mixing process and followed by heating *** Nb_2O_5/C based electrode exhibits high rate performance and remarkable cycling ability,showing a high and stable specific capacity of ~380mAhg^（-1） at the current density of 50 mAg^（-1）（much higher than the theoretical capacity of Nb_2O_5）.Further more,at a current density of 500mAg^（-1）,the nanocomposites electrode still exhibits a specific capacity of above 150 mAh g^（-1） after 100 *** results suggest the Nb_2O_5/C nanocomposite is a high performance anode material for lithium-ion batteries.

关键词： N2O5 Carbon Composite Anode Lithium-ion battery

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A theoretical and 1-D numerical investigation on a valve/valveless air-breathing pulse detonation engine

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chinese Journal of Aeronautics 2021年第1期34卷 68-78页

作者： Hua QIU cha.XIONG Jianling LI School of Power and Energy Northwestern Polytechnical UniversityXi'an 710072China State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100081China

The important operating cha.acteristics of pulsed Pressure Gain Combustion(PGC)propulsion are the pressure gain of the combustor component and the propulsive performance gain of the engine.A ramjet-type valve/valveless air-breathing pulsed detonation engine with a supersonic internal compression inlet is *** on an ideal thermal cycle,the ideal equivalent pressure ratios(pcb)of the Pulsed Detonation Combustor(PDC)are obtained theoretically which are directly related with the propulsive performance of the *** introducing an orifice loss model into the cycles,the critical pressure drop ratios through the orifice for the PDC achieving pressure gain and the engine achieving thrust gain are *** influencing factors are investigated by the use of a one-dimensional(1-D)numerical simulation *** operating cha.acteristics of the pulse detonation engine are investigated with cha.ges of the valve type,the inlet/outlet area ratio of the PDC,the nozzle area ratio,and flight *** these factors can affect pcbof the PDC,and pcbcan be optimized by cha.ging the geometry of the *** most important influence parameter is the valve *** using an orifice-type aerodynamic valve,simulation results show that the PDC cannot achieve the pressure gain *** a supersonic internal compression inlet is introduced to the engine,whether the Pulse Detonation Engine(PDE)can achieve thrust gain comparable with that of an ideal Brayton cycle engine not only is related to the pressure gain of the combustor,but also needs to optimize the engine structure to reduce the total pressure loss.

关键词： Detonation Pressure gain cha.acteristics Propulsive performance Supersonic internal compression inlet Valve/valveless Thermal cycle

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微机汽车发动机测试仪

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国外电气自动化 1989年第5期10卷 56-61页

作者： cha.,FHY 卓都

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Gelfoam embolization for distal, medium vessel injury during mecha.ical thrombectomy in acute stroke: A case report

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World Journal of Clinical Cases 2021年第20期9卷 5668-5674页

作者： Ji Yun Kang Kyung Sik Yi Sang-Hoon cha.chi-Hoon Choi Yook Kim Jisun Lee Bum Sang Cho Department of Radiology Chungbuk National University HospitalCheongju 28644South Korea College of Medicine and Medical Research Institute Chungbuk National UniversityCheongju 28644South Korea

BACKGROUND Arterial perforation has inevitably increased as endovascular treatments have become more common for intracranial large vessel occlusions,and even distal,medium vessel occlusions.A distal,medium vessel has a tortuous course and thinner wall compared to large arteries,making it more susceptible to ***,we review the treatment strategies for arterial perforation during mecha.ical thrombectomy,and we report the case of a patient treated with gelfoam *** SUMMARY A 63-year-old woman presented to the emergency department with sudden neurologic symptoms of right hemiparesis and global *** initial National Institutes of Health Stroke Scale score was *** tomography(CT)and CT angiography revealed hyperacute infarction and emergent arterial occlusion of the left middle cerebral artery M2-3 *** endovascular mecha.ical thrombectomy,arterial rupture *** patient’s vital signs were stable,but delayed angiography showed persistent active ***,selective embolization of the injured artery was performed using *** left vertebral and internal carotid angiography was performed to confirm hemostasis.A localized subarachnoid hemorrhage(SAH)was confirmed on a follow-up CT scan.A repeated CT scan after 12 d showed resolution of the SAH,and rebleeding did not *** Rescue embolization with gelfoam could be considered an additional option in distal,medium vessel perforation.

关键词： Gelfoam Embolization Acute ischemic stroke Mecha.ical thrombectomy Arterial perforation Case report

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Variations in dynamic recrystallization behavior and mecha.ical properties of AZ31 alloy with extrusion temperature

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Journal of Magnesium and Alloys 2023年第7期11卷 2351-2365页

作者： Jae Won cha.Sung Hyuk Park School of Materials Science and Engineering Kyungpook National UniversityDaegu 41566Republic of Korea

This study investigates the effects of extrusion temperature on the dynamic recrystallization(DRX)behavior of a Mg-3Al-1Zn-0.3Mn(AZ31,wt%)alloy during hot extrusion and on the microstructural cha.acteristics and mecha.ical properties of materials extruded at 350 and 450℃.An increase in the extrusion temperature causes a decrease in the amount of strain energy accumulated in the material during extrusion,because of promoted activation of pyramidalslip and dynamic *** reduced strain energy weakens the DRX behavior during extrusion,which eventually results in a decrease in the area fraction of recrystallized grains of the extruded *** material extruded at 450℃has coarser grains and a stronger basal fiber texture than that extruded at 350℃.As the extrusion temperature increases from 350 to 450℃,the tensile yield strength(TYS)of the extruded material increases from 191.8 to 201.5 MPa,whereas its compressive yield strength(CYS)decreases from 122.5 to 111.0 MPa;consequently,its tension-compression yield stress ratio(CYS/TYS)decreases from 0.64 to *** increase in the TYS is attributed mainly to the stronger texture hardening and strain hardening effects of the extruded material,and the decrease in the CYS is attributed to the reduced twinning stress resulting from grain coarsening and texture *** microstructural and textural evolutions of the materials during extrusion and the deformation and hardening mecha.isms of the extruded materials are discussed in detail.

关键词： Mg-Al-Zn alloy Extrusion Dynamic recrystallization Microstructure Yield asymmetry

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