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Continuity and Discontinuity： Narratives of the Yellow Emperor in Early Twentieth-Century History Textbooks

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Frontiers of History in China 2013年第2期8卷 176-201页

作者： Jiang Sun institute of advanced studies in Humanities and Science Nanjing University Nanjing 210093China

在中国文明的起源的学习，关于黄皇帝(Huangdi ) 的身份有可观的争论。有二条主要途径：一个人建议黄皇帝的记忆在第二十个世纪在民族性的影响下面被改变。其它主张自从古老的时间起，存储器在连续的、未改变的流被传了。由在出版在期... 详细信息

在中国文明的起源的学习，关于黄皇帝(Huangdi ) 的身份有可观的争论。有二条主要途径：一个人建议黄皇帝的记忆在第二十个世纪在民族性的影响下面被改变。其它主张自从古老的时间起，存储器在连续的、未改变的流被传了。由在出版在期间的历史课本中检验叙述关于和 Huangdi 的图象早第二十个世纪，这件物品在政治世界上作为一个符号的数字从 Huangdi 转移焦点到我们在日常世界上在检验他的接收的。因此，我们将探索不同 Huangdis，收起记忆，连续性，和断绝的方面。

关键词：非连续性教科书历史早期文明起源民族主义象征性内存

On Generalization of Cycles and Chordality to Clutters from an Algebraic Viewpoint

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Algebra Colloquium 2017年第4期24卷 611-624页

作者： Ashkan Nikseresht Rashid Zaare-Nahandi Department of Mathematics Institute for Advanced Studies in Basic Sciences P.O. Box 45195-1159 Zanjan Iran

In this paper, we study the notion of chordality and cycles in clutters from a commutative algebraic point of view. The corresponding concept of chordality in commutative algebra is having a linear resolution. We mainly consider the generalization of chordality proposed by Bigdeli et al. in 2017 and the concept of cycles introduced by Can- non and Faridi in 2013, and study their interrelations and algebraic interpretations. In particular, we investigate the relationship between chordality and having linear quotients in some classes of clutters. Also, we show that if e is a clutter such that （） is a vertex decomposable simplicial complex or I（） is squarefree stable, then is chordal.

关键词： chordal clutter squarefree monomial ideal linear resolution cycle simplicialcomplex

Uncovering growth species of multivariate MOFs in liquid phase by mass spectrometry

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Chinese Chemical Letters 2022年第8期33卷 3993-3998页

作者： Jinli Han Suming Chen Xiaochun Zhou Hexiang Deng Key Laboratory of Biomedical Polymers-Ministry of Education College of Chemistry and Molecular SciencesWuhan UniversityWuhan 430072China Division of advanced Nanomaterials Suzhou Institute of Nano-tech and Nano-bionicsChinese Academy of SciencesSuzhou 215125China The Institute for Advanced Studies Wuhan UniversityWuhan 430072China

The unveiling of MOF growth mechanism is hampered by the lack of fundamental knowledge about the very early stage of nucleation,especially the form and ratio of molecular species in the solution for crystal growth.Herein,we report the detection of growth species for a series of MOFs with mono-linker,CuMOF-2-BDC and Cu-MOF-2-NDC,and two linkers,MTV-MOF-2-(C_(4)H_(4))x,by high resolution ESI-MS,where a large variety of Cu-containing species are identified unambiguously.The solvent molecules such as H_(2)O,methanol and DMF participate in the formation of these species,other than ethanol.Furthermore,in the growth solution of MTV-MOF-2-(C_(4)H_(4))x,growth species containing two different organic linkers are observed.The feeding ratio is not the only factor controlling the distribution of growth species for MTVMOFs,but also the solvent involves in coordination,an aspect usually overlooked previously.

关键词： Metal-organic framework Multivariate MOFs Mass spectrometry Growth species Self-assembly

Oxidation-Induced C--H Functionalization： A Formal Way for C--H Activation

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Chinese Journal of Chemistry 2018年第8期36卷 692-697页

作者： Yichang Liu Hong Yi Aiwen Lei The Institute for Advanced Studies (IAS) College of Chemistry and Molecu ar Sc ences Wuhan University Wuhan Hubei 430072 China

Cross-coupling reactions have developed widely and provided a powerful means to synthesize a variety of compounds in each chemical field. The compounds which have C--H bonds are widespread in fossil fuels, chemical raw materials, biologically active molecules, etc. Using these readily- available substances as substrates is high atom- and step-economy for cross-coupling reactions. Over the past decades, our research group focused on finding and developing new strategies for C--H functionalization. Compared with classical C--H activation methods, for example, C--H bonds are depro- tonated by strong base or converted into C--M bonds, oxidation-induced C--H functionalization would be another pathway for C--H bond activation. This perspective shows a brief introduction of our recent works in this oxidation-induced C--H functionalization. We categorized this approach of these C--H bond activations by the key intermediates, radical cations, radicals and cations.

关键词： oxidation-induced C--H functionalization cross-coupling radical reactions

Hierarchical mesoporous S,N-codoped carbon nanostructures composed of Co/Co-Cu-S/carbon nanoplate arrays on carbon nanofibers as a self-supported air cathode for long-lasting rechargeable Zn-air batteries

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Science China(Technological Sciences) 2022年第3期65卷 693-703页

作者： XU ZhuYing YAN Lei SHEN JunLing YANG XiaoJing NING JiQiang ZHONG YiJun HU Yong Key Laboratory of the Ministry of Education for advanced Catalysis Materials Department of ChemistryZhejiang Normal UniversityJinhua 321004China Department of Optical Science and Engineering Fudan UniversityShanghai 200438China Hangzhou institute of advanced studies Zhejiang Normal UniversityHangzhou 311231China

One of the primary roadblocks to widespread applications of rechargeable Zn-air batteries is the durability issue with oxygen reduction and evolution processes(ORR/OER)bifunctional electrocatalysts.We herein report the construction of a selfsupported air cathode for Zn-air batteries made of S,N-codoped porous complex carbon nanostructures of Co/Co-Cu-S/carbon nanoplate arrays and carbon nanofibers(denoted as Co/Co-Cu-S@SNPCP-CFs).The hierarchical heteroatom-doped mesoporous carbon nanohybrids with multiple active species not only provide a high surface-to-volume ratio,exposing more catalytic sites and accelerating the charge and mass transfer,but also boost the activity and durability.The Co/Co-Cu-S@SNPCP-CFs catalyst reveals a small potential gap(ΔE=0.67 V)between the half-wave potential of ORR and OER potential at 10 m A ccm^(-2),demonstrating outstanding bifunctional performance.Furthermore,the rechargeable Zn-air battery made with the as-obtained electrocatalyst exhibits a high-power density of 220 m W cm^(-2)and a long cycling time of over 800 h at 10 m A ccm^(-2),and the flexible solid-state rechargeable Zn-air battery based on Co/Co-Cu-S@SNPCP-CFs self-supporting air cathode also displays a long duration time of over 60 h.

关键词： Co Co-Cu-S carbon bifunctional electrocatalyst rechargeable Zn-air batteries

A Flexible Space-Time Tradeoff on Hybrid Index with Bicriteria Optimization

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Tsinghua Science and Technology 2019年第1期24卷 106-122页

作者： Xingshen Song Yuexiang Yang Yu Jiang School of advanced Interdisciplinary studies National University of Defense Technology College of Computer National University of Defense Technology Northwest institute of Nuclear Technology

Inverted indexes are widely adopted in the vast majority of information systems. Growing requirements for efficient query processing have motivated the development of various compression techniques with different spacetime characteristics. Although a single encoder yields a relatively stable point in the space-time tradeoff curve,flexibly transforming its characteristic along the curve to fit different information retrieval tasks can be a better way to prepare the index. Recent research comes out with an idea of integrating different encoders within the same index,namely, exploiting access skewness by compressing frequently accessed regions with faster encoders and rarely accessed regions with succinct encoders, thereby improving the efficiency while minimizing the compressed size.However, these methods are either inefficient or result in coarse granularity. To address these issues, we introduce the concept of bicriteria compression, which aims to formalize the problem of optimally trading the compressed size and query processing time for inverted index. We also adopt a Lagrangian relaxation algorithm to solve this problem by reducing it to a knapsack-type problem, which works in O(n log n)time and O(n)space, with a negligible additive approximation. Furthermore, this algorithm can be extended via dynamic programming pursuing improved query efficiency. We perform an extensive experiment to show that, given a bounded time/space budget, our method can optimally trade one for another with more efficient indexing and query performance.

关键词： inverted index bicriteria compression Lagrangian relaxation

Ni-Catalyzed Enantioselective Reductive Difunctionalization of Alkenes

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Ni-Catalyzed Enantioselective Reductive Difunctionalization ...

Antisense oligonucleotide technology can be used to investigate a circular but not linear RNA-mediated function for its encoded gene locus

中国化学会·第十三届全国物理有机化学学术会议

作者： Wangqing Kong The Institute for Advanced Studies (IAS) Wuhan University

Catalytic reductive dicarbofunctionalization of alkenes involving simultaneous incorporation of two carbon electrophiles across the double bond in a single operation have received increasing attention in recent years. As they represent a powerful tool for the construction complex and useful compounds with stereocenters, and allow reactions to proceed under mild conditions with high functional-group compatibility, without any additional prepreparation of sensitive organometallics in comparison to classical alkene difunctionalization with one carbon nucleophile and one carbon electrophile. Although there have been several reports in recent years on racemic reactions, highly enantioselective versions of these processes are not yet reported. We reported the first examples of Ni-catalyzed high enantioselective reductive diarylation of alkenes by domino cyclizative/cross-coupling of two aryl bromides. Moreover, a highly regio-and enantioselective reductive cyclization of acrylamides with internal alkynes to 2,3-fused cyclopentannulated indolines had also been developed(Scheme 1). Very recently, we reported an enantioselective reductive aryl-monofluoroalkenylation reaction of aryl bromides with gem-difluoroalkenes. These reactions proceed under very mild conditions and show broad substrate scope, without requiring the use of preformed organometallic reagents. This approach provides direct access to various nitrogen-containing heterocycles bearing all-carbon quaternary centers in good yields with excellent enantioselectivities.

关键词： Asymmetric catalysis alkene difunctionalization reductive coupling nickel-catalyst

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Science China(Life Sciences) 2021年第5期64卷 784-794页

作者： Zhenxing Song Ruirui Jia Mingfeng Tang Fei Xia Haiyang Xu Zhengguo Li Chuan Huang School of Life Sciences Chongqing UniversityChongqing 400044China Center of Plant Functional Genomics Institute of Advanced Interdisciplinary StudiesChongqing UniversityChongqing 400044China

As a class of powerful molecular tool,antisense oligonucleotides(ASOs)are not only broadly used in protein and RNA biology,but also a highly selective therapeutic strategy for many diseases.Although the concept that ASO reagents only reduce expression of the targeted gene in a post-transcriptional manner has long been established,the effect and mechanism of ASO reagents on RNA polymerase II(Pol II)transcription are largely unknown.This raised question is particularly important for the appropriate use of ASOs and the valid interpretation of ASO-mediated experiments.In this study,our results show that linear RNA ASO attenuates transcription of nascent transcripts by inducing premature transcription termination which is combinatorially controlled by Integrator,exosome,and Rat1 in Drosophila.However,circular RNA(circRNA)ASO transfection does not affect transcription activity of the encoded gene.These data suggest that the ASO technique can be applied to study a circRNA-mediated but not linear RNA-mediated function for its encoded gene locus.

关键词： antisense oligonucleotide premature transcription termination circular RNA linear RNA

Sulfur-doped CMK-5 with expanded lattice for high-performance lithium ion batteries

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Chinese Chemical Letters 2023年第7期34卷 279-283页

作者： Zhenjin Liang Yuhao Peng Xing Zhang Kewei Cao Wei Xiao Dong Gu The Institute for Advanced Studies Wuhan UniversityWuhan 430072China College of Chemistry and Molecular Sciences Hubei Key Laboratory of Electrochemical Power SourcesWuhan UniversityWuhan 430072China

Heteroatom-doped porous carbon materials are very attractive for lithium ion batteries(LIBs) owing to their high specific surface areas, open pore structures, and abundant active sites. However, heteroatomdoped porous carbon with very high surface area and large pore volume are highly desirable but still remain a big challenge. Herein, we reported a sulfur-doped mesoporous carbon(CMK-5-S) with nanotubes array structure, ultrahigh specific surface area(1390 m^(2)/g), large pore volume(1.8 cm^(3)/g), bimodal pore size distribution(2.9 and 4.6 nm), and high sulfur content(2.5 at%). The CMK-5-S used as an anode material for LIBs displays high specific capacity, excellent rate capability and highly cycling stability. The initial reversible specific capacity at 0.1 A/g is as high as 1580 mAh/g and simultaneously up to 701 mAh/g at 1A/g even after 500 cycles. Further analysis reveals that the excellent electrochemical storage performances is attributed to its unique structures as well as the expanded lattice by sulfur-doping.

关键词： Mesoporous material CMK-5 Hollow structure Sulfur-doping Lithium ion batteries