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Competing reduction induced homogeneous oxygen doping to unlock MoS_(2)basal planes for faster polysulfides conversion

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Journal of Energy Chemistry 2022年第10期31卷 26-34,I0002页

作者： Da Lei wenzhe shang Xu Zhang Yongpeng Li Xiaoshan Shi Shaoming Qiao Qian Wang Qiang Zhang Ce Hao Hui Xu Guohua Chen Gaohong He Fengxiang Zhang State Key Laboratory of Fine Chemicals Dalian University of TechnologyDalian 116024LiaoningChina School of Chemical Engineering Dalian University of TechnologyPanjin 124221LiaoningChina Shenzhen ApogeeTec Greenergy Co.Ltd. Shenzhen 518000GuangdongChina Department of Mechanical Engineering Research Institute for Smart EnergyThe Hong Kong Polytechnic UniversityKowloonHong Kong 999077China

The parasitic polysulfides shuttle effect greatly hinders the practical application of lithium sulfur batteries,and this issue can be addressed by promoting polysulfides conversion with catalytic materials such as Mo S_(2).However,the catalytic activity of Mo S_(2)mainly relies on edge sites,but is limited by inert basal planes.We herein report a novel,facile,ethylene glycol enabled competing reduction strategy to dope Mo S_(2)homogeneously with oxygen atoms so that its inert basal planes can be unlocked.Ethylene glycol works as a reducing agent and competes with thiourea to react with ammonium molybdate,leading to insufficient sulfuration of Mo,and consequent formation of O-Mo S_(2).Our theoretical and experimental investigations indicate that the homogeneously distributed O dopants can create abundant adsorption/-catalytic sites in the Mo S_(2)basal planes,enlarge the inter-plane distance to promote ion transport,and thus enhance the catalytic conversion of polysulfides.The oxygen doped Mo S_(2)(O-Mo S_(2))is supported on carbon nanosheets(CNS)and the composite(O-Mo S_(2)/CNS)is employed to modify the separator of Li-S battery.It gives the battery an initial discharge capacity of 1537 m Ah g-1at 0.2 C,and the battery retains a discharge capacity of 545 m Ah g-1after ultra-long 2000 cycles at 1 C,corresponding to a very small cyclic decay rate of 0.0237%.Even under a raising sulfur loading of 8.2 mg cm^(-2),the Li-S battery also delivers a high discharge capacity(554 m Ah g^(-1))with outstanding cycle stability(84.6%capacity retention)after 100 cycles at 0.5 C.Our work provides a novel,facile approach to fabricate highly catalytically active oxygen-doped Mo S_(2)for advanced Li-S batteries.

关键词： Competing reduction One-pot Oxygen-doped MoS_(2) Unlocked basal plane Li-S batteries

完全暴露的碳基电极边缘-平面位点用于高效水氧化

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Chinese Journal of Catalysis 2024年第5期60卷 272-283页

作者：郭静雅刘炜商文喆司端惠朱超胡金文辛存存程旭升张松林宋俗禅王秀云史彦涛大连理工大学化学学院精细化工国家重点实验室智能材料前沿科学中心辽宁大连116024 中国科学院福建物质结构研究所结构化学国家重点实验室福建福州350002 东南大学微机械系统教育部重点实验室东南大学纳皮米中心江苏南京210096

开发经济高效的析氧反应电催化剂对于推进可充电金属-空气电池和电解水技术的发展至关重要.一般来说,具有完整蜂窝结构的石墨碳基面是电化学惰性的,需要依赖缺陷或者掺杂结构诱导的电荷极化效应来提升催化活性.相比于基面,边缘位点具有... 详细信息

开发经济高效的析氧反应电催化剂对于推进可充电金属-空气电池和电解水技术的发展至关重要.一般来说,具有完整蜂窝结构的石墨碳基面是电化学惰性的,需要依赖缺陷或者掺杂结构诱导的电荷极化效应来提升催化活性.相比于基面,边缘位点具有特殊的局域电子态,为提升石墨碳电极的本征催化活性开辟了新的思路,然而其结构精准构筑目前仍面临极大挑战.本文以“人字形”多壁碳纳米管(H-MWCNTs)作为研究切入点,利用高温熔盐介质主导的插层剥离和截断效应,实现“边缘-平面位点”结构可控构筑,为实现高效电解水析氧反应(OER)提供了重要的结构基础.通过熔盐辅助热解方法可控制备了具有完全暴露的内外边缘平面的目标催化剂H-MWCNTs-MS,并研究其OER催化性能.在碱性介质中10 mA cm^(-2)电流密度所需过电位仅为236 mV,是目前报道的较好的非金属电催化剂.同时,H-MWCNTs-MS在10,50和100 mA cm^(-2)电流密度下均表现出较好的电化学稳定性.利用原位衰减全反射-表面增强红外吸收光谱(ATR-SEIRAS)技术研究了“边缘-平面位点”在OER过程中的结构重构过程,与理论计算分析的高能“边缘态”结果一致,并确定酮氧官能化位点为真实催化活性中心.理论计算结果表明,氧官能团修饰结构能够显著促进电荷的再分配,增强层间耦合作用,降低关键含氧中间体*OOH的形成能垒,加速OER反应动力学.此外,H-MWCNTs-MS的开放式结构极大程度提高了“边缘-平面位点”的利用率,减小的纳米管壁厚促进了层间电荷迁移,也是增强OER活性的关键要素.综上,精准构筑“边缘-平面位点”为开发高效石墨碳电极开辟了新的思路,通过原位谱学技术揭示边缘位点催化结构重构,能够进一步丰富研究者对于电催化协同效应的科学认识.

关键词：多壁碳纳米管边缘-平面位点析氧反应熔融盐电子耦合

China's current forest age structure will lead to weakened carbon sinks in the near future

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The Innovation 2023年第6期4卷 38-47页

作者： Rong shang Jing M.Chen Mingzhu Xu Xudong Lin Peng Li Guirui Yu Nianpeng He Li Xu Peng Gong Liangyun Liu Han Liu wenzhe Jiao Key Laboratory for Humid Subtropical Eco-Geogr aphical Processes of the Ministy of Education School of Geographical SciencesFujian Normal UniversityFuzhou 350117China Department of Geography and Planning University of TorontoTorontoOntario M5S 3G3Canada Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBejing 100101China Institute for Climate and Carbon Neutrality Department of Geography and Department of Earth SciencesUniversity of Hong KongHong Kong 999077China International Research Center of Big Data for Sustainable Development Goals Beijing 100094China Land Consolidation and Rehabilitation Center Ministry of Natural ResourcesBeijing 100035China Department of Civil and Environmental Engineering Massachusetts Institute of TechnologyCambridgeMA 02139USA

Forests are chiefly responsible for the terrestrial carbon sink that greatly re duces the buildup of CO_(2)concentrations in the atmosphere and alleviates climate change.Current predictions of terrestrial carbon sinks in the future have so far ignored the variation of forest carbon uptake with forest age.Here,we predict the role of China's current forest age in future carbon sink capacity by generating a high-resolution(30 m)forest age map in 2019 over China's landmass using satellite and forest inventory data and deriving forest growth curves using measurements of forest biomass and age in 3,121 plots.As China's forests currently have large proportions of young and middle-age stands,we project that China's forests will maintain high growth rates for about 15 years.However,as the forests grow older,their net primary productivity will decline by 5.0%±1.4%in 2050,8.4%±1.6%in 2060,and 16.6%±2.8%in 2100,indicating weakened carbon sinks in the near future.The weakening of forest carbon sinks can be potentially mitigated by optimizing forest age structure through selective logging and implementing new or improved afforestation.This finding is important not only for the global carbon cycle and climate projections but also for developing forest management strategies to enhance land sinks by alleviating the age effect.

关键词： forest carbon structure

A Survey of Vision and Language Related Multi-Modal Task

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CAAI Artificial Intelligence Research 2022年第2期1卷 111-136页

作者： Lanxiao Wang wenzhe Hu Heqian Qiu Chao shang Taijin Zhao Benliu Qiu King Ngi Ngan Hongliang Li Department of Information and Communication Engineering University of Electronic Science and Technology of ChinaChengdu 611731China The Chinese University of Hong Kong Hong Kong 999077China

With the significant breakthrough in the research of single-modal related deep learning tasks,more and more works begin to focus on multi-modal tasks.Multi-modal tasks usually involve more than one different modalities,and a modality represents a type of behavior or state.Common multi-modal information includes vision,hearing,language,touch,and smell.Vision and language are two of the most common modalities in human daily life,and many typical multi-modal tasks focus on these two modalities,such as visual captioning and visual grounding.In this paper,we conduct in-depth research on typical tasks of vision and language from the perspectives of generation,analysis,and reasoning.First,the analysis and summary with the typical tasks and some pretty classical methods are introduced,which will be generalized from the aspects of different algorithmic concerns,and be further discussed frequently used datasets and metrics.Then,some other variant tasks and cutting-edge tasks are briefly summarized to build a more comprehensive vision and language related multi-modal tasks framework.Finally,we further discuss the development of pre-training related research and make an outlook for future research.We hope this survey can help relevant researchers to understand the latest progress,existing problems,and exploration directions of vision and language multi-modal related tasks,and provide guidance for future research.

关键词： deep learning vision and language multi-modal generation multi-modal analysis multi-modal reasoning pre-training

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论“尚书体”的文化内涵与文体特征

中国文学研究 2022年第2期 41-48页

作者：于文哲山西师范大学学报编辑部山西太原030031

《尚书》作为儒家五经之一,对我国古代政治制度、思想文化以及社会生活的各个方面均产生了重大而深远的影响,其对文学的影响,集中体现在文体方面。关于《尚书》文体,除了传统的“六体“”十体”等分体论说外,历史上还存在着对《尚书》... 详细信息

《尚书》作为儒家五经之一,对我国古代政治制度、思想文化以及社会生活的各个方面均产生了重大而深远的影响,其对文学的影响,集中体现在文体方面。关于《尚书》文体,除了传统的“六体“”十体”等分体论说外,历史上还存在着对《尚书》文体特征的整体论说,其中“尚书体”概念的出现,标志着古人对《尚书》文体认识的深化。“尚书体”植根于古代社会文化传统、审美心理的丰厚土壤中,蕴藏着深厚的历史文化内涵,存在着可供深入开拓的研究空间。本文从文体地位、使用场合、文本制作、文体演变等几个方面,借鉴现代文体学和文化理论,对“尚书体”的历史文化内涵和文体特征作初步的总结概括,以期从新的视角推动《尚书》文体与文学研究的深入开展。

关键词：《尚书》 “尚书体” 文体特征文化内涵

The existence of a nonclassical TCA cycle in the nucleus that wires the metabolic-epigenetic circuitry

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Signal Transduction and Targeted Therapy 2021年第12期6卷 3666-3683页

作者： Xujun Liu wenzhe Si Lin He Jianguo Yang Yani Peng Jie Ren Xiaoping Liu Tong Jin Huajing Yu Zihan Zhang Xiao Cheng Wenting Zhang Lu Xia Yunchao Huang Yue Wang Shumeng Liu Lin Shan Yu Zhang Xiaohan Yang Haixia Li Jing Liang Luyang Sun Yongfeng shang Key Laboratory of Carcinogenesis and Translational Research(Ministry of Education) Department of Biochemistry and Molecular BiologyDepartment of Laboratory MedicinePeking University Third HospitalSchool of Basic Medical SciencesPeking University Health Science Center100191 BeijingChina Department of Clinical Laboratory Peking University First Hospital100034 BeijingChina Department of Biochemistry and Molecular Biology School of Basic Medical SciencesHangzhou Normal University311121 HangzhouChina Department of Biochemistry and Molecular Biology School of Basic Medical SciencesCapital Medical University100069 BeijingChina Department of Integration of Chinese and Western Medicine School of Basic Medical SciencesPeking University Health Science Center100191 BeijingChina

The scope and variety of the metabolic intermediates from the mitochondrial tricarboxylic acid(TCA)cycle that are engaged in epigenetic regulation of the chromatin function in the nucleus raise an outstanding question about how timely and precise supply/consumption of these metabolites is achieved in the nucleus.We report here the identification of a nonclassical TCA cycle in the nucleus(nTCA cycle).We found that all the TCA cycle-associated enzymes including citrate synthase(CS),aconitase 2(ACO2),isocitrate dehydrogenase 3(IDH3),oxoglutarate dehydrogenase(OGDH),succinyl-CoA synthetase(SCS),fumarate hydratase(FH),and malate dehydrogenase 2(MDH2),except for succinate dehydrogenase(SDH),a component of electron transport chain for generating ATP,exist in the nucleus.We showed that these nuclear enzymes catalyze an incomplete TCA cycle similar to that found in cyanobacteria.We propose that the nTCA cycle is implemented mainly to generate/consume metabolic intermediates,not for energy production.We demonstrated that the nTCA cycle is intrinsically linked to chromatin dynamics and transcription regulation.Together,our study uncovers the existence of a nonclassical TCA cycle in the nucleus that links the metabolic pathway to epigenetic regulation.

关键词： metabolic cycle Together

聚癸二酸甘油酯/生物活性玻璃/GR复合材料制备与性能

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工程塑料应用 2022年第8期50卷 30-36页

作者：韩浩瀛尚志福张毅张文哲李雨泽郭赢繁刘增辉施惠红张秀成东北林业大学化学化工与资源利用学院哈尔滨150040

采用癸二酸与甘油共聚合成聚癸二酸甘油酯(PGS)做为基体,采用溶胶-凝胶法制备生物活性玻璃(BG)并与石墨烯(GR)一并做为增强体,制备了PGS/BG/GR复合材料。研究了PGS/BG/GR复合材料的力学性能、亲水性和结晶性等性能。结果表明,BG,GR均对... 详细信息

采用癸二酸与甘油共聚合成聚癸二酸甘油酯(PGS)做为基体,采用溶胶-凝胶法制备生物活性玻璃(BG)并与石墨烯(GR)一并做为增强体,制备了PGS/BG/GR复合材料。研究了PGS/BG/GR复合材料的力学性能、亲水性和结晶性等性能。结果表明,BG,GR均对PGS的力学性能起到了增强作用,当BG质量分数为2%,GR质量分数为5%时,PGS/BG/GR复合材料的拉伸强度为纯PGS的3.57倍、拉伸弹性模量为纯PGS的5.5倍。BG与GR的协同作用使复合材料的亲水性得到显著改善,PGS/BG/GR复合材料的接触角可达到30.7°,较纯PGS降低了58.7%。PGS/BG/GR复合材料的残炭率提高,最大结晶速率温度降低至–3.09℃。PGS/BG/GR复合材料的拉伸弹性模量和人体皮肤十分接近,其优良的亲水性有利于皮肤创伤处组织液的吸收,这种具有较高拉伸强度和亲水性的PGS/BG/GR复合材料在生物医学领域有着良好的应用前景和使用价值。

关键词：聚癸二酸甘油酯石墨烯生物活性玻璃力学性能润湿性

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《尚书》虞舜神话溯源

学术交流 2011年第3期 175-179页

作者：于文哲山西师范大学学报编辑部山西临汾041004

《尚书》叙事富于神话的想象和幻想,保留了大量上古原始神话的片段,尤其是《虞夏书》,更可以看作是历史化了的我国上古神话与传说的汇集。其中,有关虞舜的神话和有关鲧禹治水的神话构成了《虞夏书》的核心部分。这些神话内容使《尚书》... 详细信息

《尚书》叙事富于神话的想象和幻想,保留了大量上古原始神话的片段,尤其是《虞夏书》,更可以看作是历史化了的我国上古神话与传说的汇集。其中,有关虞舜的神话和有关鲧禹治水的神话构成了《虞夏书》的核心部分。这些神话内容使《尚书》在历史叙事之外,更增添了由想象与幻想等虚构叙事所带来的形象性,使故事情节更为曲折复杂、绚丽多彩,人物形象更为丰满生动。本文以《尚书》的虞舜神话为研究对象,追溯并分析该神话的原型意义,以期说明神话内容对《尚书》叙事文学性的深刻影响。

关键词：《尚书》虞舜上古神话

光系统Ⅱ光驱动CO2同化的光合作用(英文)

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Chinese Journal of Catalysis 2023年第1期44卷 117-126页

作者：李跃辉司端惠王旺银薛松商文喆迟占有李灿郝策 Govindjee Govindjee 史彦涛大连理工大学化工学院化学系，智能材料化工前沿科学中心，精细化工国家重点实验室中国科学院大连化学物理研究所，催化基础国家重点实验室，洁净能源国家实验室(筹) 大连理工大学生物工程学院伊利诺伊大学厄巴纳香槟分校，生物化学系，植物生物学系和生物物理学与定量生物学中心

光合作用作为地球上最重要的化学反应,是一切生命活动赖以生存的基础.光合作用分为光反应和暗反应两个阶段.通常认为,光反应阶段产生O2,暗反应阶段CO2被还原(也称“CO2同化”).尽管这一观点已被公众所熟知,但也存在诸多疑点,一些科学家... 详细信息

光合作用作为地球上最重要的化学反应,是一切生命活动赖以生存的基础.光合作用分为光反应和暗反应两个阶段.通常认为,光反应阶段产生O2,暗反应阶段CO2被还原(也称“CO2同化”).尽管这一观点已被公众所熟知,但也存在诸多疑点,一些科学家(包括1931年的诺贝尔生理学或医学奖得主OttoWarburg)认为, CO2也可能在光反应阶段作为反应底物参与了产氧并被还原.然而,该观点至今没有在实验上获得充足的证据支持.那么,在光反应阶段是否能够进行CO2同化？如果能够发生,产物和机理是什么？毫无疑问,这些科学问题具有十分重要的研究价值,对这些问题的探索能帮助我们更加充分认识光合作用机制.然而,自上世纪十年代以来,相关研究已陷入停滞状态.为了解开光合作用领域的这个重要科学谜团,即在光合作用中CO2是否能通过光反应被还原,本文选取三类不同层次的光合作用体系(小球藻、叶绿体、PSII中心复合体)为研究对象,结合原位质谱、气相色谱和同位素标记等手段,设计了一系列实验,排除了呼吸作用和其它因素干扰,实验发现在光反应阶段PSII中心复合体不但产生O2,还能产生C1化合物CH3OH.13CO2和C18O2标记实验结果表明, CH3OH来源于CO2光还原,排除了CH3OH来自于光呼吸或细胞壁果胶脱甲基分解的可能.说明光合作用光反应阶段能够进行CO2还原,反应场所是PSII中心复合体,这与CO2的同化只能发生在暗反应阶段的传统观点相矛盾.因此,除了非光依赖性CO2同化这一已知路径外,还有一条未知的光驱动CO2同化路径.进一步推测,这种CO2光还原路径可能与暗反应下的CO2同化同时进行.目前,对这种光驱动下CO2同化机制仍需进一步深入研究.综上,本文丰富了人们对光合作用机理以及CO2同化路径的认知,并为长期以来存在争议的CH3OH来源问题提供了新解释.

关键词：光合作用 PSII中心复合体光反应 CO2同化甲醇