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Axially N-Embedded Quasi-Carbon Nanohoops with Multioxidation States

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CCS Chemistry 2023年第8期5卷 1763-1772页

作者： Shuhai Qiu Yongye Zhao Li Zhang Yong Ni Yanan wu Huan Cong Da-Hui Qu Wei Jiang jishan wu He Tian Zhaohui Wang Key Laboratory for Advanced Materials and Joint International Research Laboratory of Precision Chemistry and Molecular Engineering Feringa Nobel Prize Scientist Joint Research CenterFrontiers Science Center for Materiobiology and Dynamic ChemistryInstitute of Fine ChemicalsSchool of Chemistry and Molecular EngineeringEast China University of Science and TechnologyShanghai 200237 Key Laboratory of Photochemical Conversion and Optoelectronic Materials Technical Institute of Physics and Chemistry and University of Chinese Academy of SciencesChinese Academy of SciencesBeijing 100190 Department of Chemistry National University of SingaporeSingapore 117543 Key Laboratory of Organic Optoelectronics and Molecular Engineering Department of ChemistryTsinghua UniversityBeijing 100084

The incorporation of heteroatoms into carbon nanohoops can significantly overcome aromatic stabilization energy and enrich their physicochemical properties depending on the positions and numbers of the doped *** a V-shaped dipyreneo[c,e]dihydrophenazine as the building block,herein we report a novel kind of axially N-embedded quasi-carbon nanohoops by integratingπ-extended dihydropyrazine and para-phenylene *** X-ray diffraction analyses revealed that their geometrical structures varied from droplet-shaped geometry for DPP-M and suppressed elliptical cross-section configuration for DPP-D to triangularly prismatic configuration for *** measurements confirmed rich electronic properties,especially multioxidation behaviors due to the embedding of graphitic-N atoms,which are not observed in carbonaceous nanohoops and other *** investigations,including electron spin resonance spectroscopy,theoretical calculations,and single-crystal structure analyses,on the oxidized species of both DPP-D and DPP-T demonstrated their tunable open-shell ground states for the *** work provides a new synthetic strategy to axially N-embedded quasi-carbon nanohoops and gives insights into the design of structure-precise segments of graphitic-N-doped single-walled carbon nanotubes.

关键词： N-embedded macrocycles Yamamoto coupling reactions geometrical structures redox properties dications

Benzo[1,2-c;4,5-c']bis[1,2,5]thiadiazole-porphyrin-based near-infrared dyes

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SmartMat 2021年第3期2卷 398-405页

作者： Yi Liu Shaofei wu Tullimilli Y.Gopalakrishna jishan wu Department of Chemistry National University of SingaporeSingaporeSingapore Joint School of National University of Singapore and Tianjin University International Campus of Tianjin UniversityFuzhouBinhai New CityChina

Benzo[1,2-c;4,5-cʹ]bis[1,2,5]thiadiazole(BBT)has intrinsic diradical character and herein it is used to construct organic near-infrared(NIR)dyes together with the aromatic porphyrin *** BBT-porphyrin hybrid dyes 1-3 with different linkage modes are synthesized by Pd-catalyzed Sonogashira crosscoupling between meso-ethynylene porphyrin units and monobromo-/dibromo-BBT,or through unexpected homocoupling between the BBT *** all possess small open-shell diradical character and display intense NIR absorption in the range of 800-1000 *** also exhibit amphoteric redox ***-based diradicaloids are thus good candidates for organic NIR dyes.

关键词： benzo[1,2-c 4,5-c']bisthiadiazole diradical character near-infrared dye porphyrin

CsPbBr_(3)quantum dots/PDVT-10 conjugated polymer hybrid film-based photonic synaptic transistors toward high-efficiency neuromorphic computing

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Science China Materials 2022年第11期65卷 3077-3086页

作者： Congyong Wang Qisheng Sun Gang Peng Yujie Yan Xipeng Yu Enlong Li Rengjian Yu Changsong Gao Xiaotao Zhang Shuming Duan Huipeng Chen jishan wu Wenping Hu Joint School of National University of Singapore and Tianjin University International Campus of Tianjin UniversityBinhai New CityFuzhou 350207China Department of Chemistry National University of Singapore3 Science Drive 3Singapore 117543Singapore Tianjin Key Laboratory of Molecular Optoelectronic Sciences Department of ChemistrySchool of ScienceTianjin University&Collaborative Innovation Center of Chemical Science and Engineering(Tianjin)Tianjin 300072China Institute of Optoelectronic Display National&Local United Engineering Lab of Flat Panel Display TechnologyFuzhou UniversityFuzhou 350002China Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China Fuzhou 350100China School of Materials Science and Engineering Xiamen University of TechnologyXiamen 361024China

Photonic synaptic transistors are promising neuromorphic computing systems that are expected to circumvent the intrinsic limitations of von Neumann-based *** design and construction of photonic synaptic transistors with a facile fabrication process and highefficiency information processing ability are highly desired,while it remains a tremendous ***,a new approach based on spin coating of a blend of CsPbBr_(3) perovskite quantum dot(QD)and PDVT-10 conjugated polymer is reported for the fabrication of photonic synaptic *** combination of flat surface,outstanding optical absorption,and remarkable charge transporting performance contributes to high-efficiency photon-to-electron conversion for such perovskite-based ***-performance photonic synaptic transistors are thus fabricated with essential synaptic functionalities,including excitatory postsynaptic current(EPSC),paired-pulse facilitation(PPF),and long-term *** utilizing the photonic potentiation and electrical depression features,perovskite-based photonic synaptic transistors are also explored for neuromorphic computing simulations,showing high pattern recognition accuracy of up to 89.98%,which is one of the best values reported so far for synaptic transistors used in pattern *** work provides an effective and convenient pathway for fabricating perovskite-based neuromorphic systems with high pattern recognition accuracy.

关键词： CsPbBr_(3)quantum dots photonic synaptic transistor synaptic functionalities neuromorphic computing pattern recognition accuracy

Debris Flow Dam Formation in Southeast Tibet

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Journal of Mountain Science 2005年第2期2卷 155-163页

作者： CHENG Zunlan wu jishan GENG Xueyong Institute of Mountuin Hazards and Environment Chinese Academy of SHences ＆ Ministry of Water Conservancy Chengdu Sichuan 610041 China

Glaciers with their deposits abound in the alpine areas of Southeast Tibet. Large debris flows occur frequently from these deposits and form dams that block streams. In this paper,3 events of large debris flows reported in Peilong Valley located in Southeast Tibet,and which resulted 2 blocking dams resulted,are discussed in details,focusing on the major factors controlling dam formation. The results shows that the first surge group caused by snow and ice avalanches,ice-lake breaks,and large-scale landslides,with a high peak discharge and high velocity,and an abundance of boulders,are most likely to form blocking dams.

关键词： Southeast Tibet debris-flow dam dam formation

Stable Quadruple Helical Tetraradicaloid with Thermally Induced Intramolecular Magnetic Switching

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CCS Chemistry 2022年第1期4卷 95-103页

作者： Jing Guo Zhiyu Li Jun Zhang Bo Li Yuan Liang Yanpei Wang Sheng Xie Hoa Phan Tun Seng Herng Jun Ding jishan wu Ben Zhong Tang Zebing Zeng State Key Laboratory of Chemo/Biosensing and Chemometrics College of Chemistry and Chemical Engineering/Shenzhen Research InstituteHunan UniversityChangsha 410082 School of Materials and Chemical Engineering Anhui Jianzhu UniversityHefei 230039 Jiurui Biotechnology Co. Ltd.Zhangjiajie 427000 Department of Chemistry National University of SingaporeSingapore 117543 Department of Materials Science and Engineering National University of SingaporeSingapore 119260 Department of Chemistry Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and ReconstructionInstitute for Advanced Study and HKUST-Shenzhen Research InstituteSCUT-HKUST Joint Research InstituteHong Kong University of Science and TechnologyHong Kong 999077

We report an air-stable tetraradicaloid based on a rarely explored perylenequinonoid(PQ)core,namely,tetrabenzo-annulated tetracyclopenta[b,e,k,n]perylene(TBCP),which has a quadruple helical *** validated by X-ray crystallographic analysis and theoretical calculations,the nonplanar TBCP possesses unique hybrid resonance structures of two open-shell singlet ***,magnetic measurements reveal that TBCP in powder form shows unusual magnetic hysteresis upon heating followed by cooling,corresponding to interconversion of structure isomers with different magnetic *** electronic properties can be rationalized as the response of structural changes to external thermal stimuli,accompanied by a subtle balance of two types of intramolecular magnetic interactions between four-site spin *** results provide a novel organic polyradicaloid as an unprecedented example of a functional material with the potential for intramolecular magnetic switching.

关键词： polycyclic hydrocarbons polyradicaloid electronic structure singlet-to-triplet energy gap intramolecular magnetic interaction

Facile Synthesis of Aryl-Substituted Cycloarenes via Bismuth(III)Triflate-Catalyzed Cyclization of Vinyl Ethers

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CCS Chemistry 2021年第5期3卷 1445-1452页

作者： Wei Fan Yi Han Shaoqiang Dong Guangwu Li Xuefeng Lu jishan wu Department of Chemistry National University of SingaporeSingapore 117543 Department of Materials Science Fudan UniversityShanghai 200438 Joint School of National University of Singapore and Tianjin University International Campus of Tianjin UniversityFuzhou 350207

Cycloarenes are an essential class of polycyclic aromatic hydrocarbons with unique electronic structure,but their synthesis is very ***,we report a facile synthetic strategy primarily involving macrocyclization by the Suzuki coupling reaction,followed by bismuth(III)triflate-catalyzed cyclization of vinyl *** utilizing this approach,aryl-substituted soluble cycloarenes 7 and 8 with different sizes were obtained.X-ray crystallographic analysis revealed a slightly distorted backbone in the kekulene derivative 7 and a saddle-shaped skeleton in the octulene derivative *** length analysis suggested that both of the cycloarenes mainly complied with the Clar’s bonding model with dominant local aromaticity,which was also in accord with our NMR measurements and the theoretical calculations[nucleus-independent chemical shift[NICS],anisotropy of the induced current density(ACID),three-dimensional isochemical shielding surface(3D ICSS)].The optical properties were investigated by UV-Vis absorption and fluorescence spectral *** method opens opportunities to access various expanded and core-modified cycloarenes in the future.

关键词： polycyclic aromatic hydrocarbon cycloarene kekulene octulene aromaticity

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Author Spotlight

CCS Chemistry 2021年第5期3卷 I0004-I0005,1231页

作者： Ma, Shengqian wu, jishan Zhang, Xingang Argonne Natl Lab Argonne IL 60439 USA Univ S Florida Dept Chem Tampa FL 33620 USA Univ North Texas Dept Chem Denton TX USA Univ Calif Los Angeles Los Angeles CA USA NUS Dept Chem Singapore Singapore Univ Illinois Urbana IL 61801 USA

Shengqian Ma(马胜前)*** Ma obtained his *** from Jilin University in 2003 and graduated from Miami University(Ohio,USA)with a *** in *** finishing a two-year Director’s Postdoctoral Fellowship at Argonne National Laboratory(USA),he joined the Department of Chemistry at the University of South Florida(USA)as an Assistant Professor in August *** was promoted to Associate Professor with early tenure in 2015 and Full Professor in *** August 2020,he joined the Department of Chemistry at the University of North Texas(USA)as the Robert *** Chair in *** current research focuses on task-specific design and functionalization of advanced nanoporous materials including metal-organic framework,covalent organic framework,and porous organic polymer for energy,biological,environmental-related *** has received a number of awards during his research career,including NSF CAREER Award(2014),IUPAC Prize for Young Chemists(2009),and Young Investigator Award from American Chemical Society Division of Inorganic Chemistry(2008).

关键词： finishing Director doctor

Surface molecular doping of all-inorganic perovskite using zethrenes molecules

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Nano Research 2019年第1期12卷 77-84页

作者： Arramel Hu Pan Aozhen Xie Songyan Hou Xinmao Yin Chi Sin Tang Nguyen T.Hoa Muhammad D.Birowosuto Hong Wang Cuong Dang Andrivo Rusydi Andrew T.S.Wee jishan wu Department of Physics National University of Singapore2 Science Drive 3Singapore 117542Singapore Centre for Advanced 2D Materials National University of SingaporeBlock S14Level 66 Science Drive 2Singapore 117546Singapore Department of Chemistry National University of Singapore3 Science Drive 3Singapore 117543Singapore CINTRA UMICNRS/NTU/THALES 3288 Research Techno Plaza50 Nanyang DriveLevel 6Border X BlockSingapore 637553Singapore School of Electrical and Electronic Engineering Nanyang Technological University50 Nanyang AvenueSingapore 639798Singapore Energy Research Institute@NTU(ERI@N) Nanyang Technological UniversityResearch Techno PlazaX-Frontier BlockLevel 550 Nanyang DriveSingapore 637553Singapore Singapore Synchrotron Light Source National University of Singapore5 Research LinkSingapore 1176033Singapore NUS Graduate School for Integrative Sciences and Engineering(NGS) National University of SingaporeSingapore 117456Singapore NUSNNI-NanoCore National University of SingaporeSingapore 117411Singapore Institute of Materials Research&Engineering(IMRE) Agency far ScienceTechnology and Research(A^*STAR)2 Fusionopolis WayInnovisSingapore 138634Singapore

We present an optical and photoelectron spectroscopic study to elucidate the interfacial electronic properties of organic-inorganic semiconductor heterojunctions formed in a kinetically blocked heptazethrene triisopropylsilyl ethynylene (HZ-TIPS) and its homologue,octazethrene (OZ-TIPS) on an all-inorganic perovskite cesium lead bromide (CsPbBr3) *** photoluminescence behavior of the underlying perovskites upon differing molecular doping conditions was *** turns out that the charge transfer dynamics of thermally-evaporated OZ-TIPS molecule exhibited a faster average lifetime than that of the HZ-TIPS case suggesting the importance of the biradical state in the former *** interfacial dipole was formed at the interface due to the competing interaction between the dispersion force of the bulky TIPS-substituent group and the attractive van der Waals interaction at the first few *** spectroscopy of the physisorbed HZ-TIPS shows chemical shifts,which indicates electron transfer from HZ-TIPS molecules to the CsPbBr3 perovskite single *** contrast,the adsorbed OZ-TIPS molecular layer on CsPbBr3 demonstrates the opposite trend indicating a hole transfer *** average molecular orientation as determined by near edge X-ray absorption fine structure (NEXAFS) suggests that the HZ-TIPS molecular plane is generally lifted with respect to the perovskite *** suggest that the nature of the closed-shell electronic ground state of HZ-TIPS could contribute to the formation of interfacial dipole at the molecule/perovskite interface.

关键词： zethrene photoelectron spectroscopy perovskite near edge X-ray absorption fine structure and molecular doping

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应当避免对高校图书馆向社会开放的误读

大学图书馆学报 2009年第3期27卷 16-19页

作者：武继山中国人民大学图书馆北京100872

高校图书馆向社会开放是高校图书馆在完成对本校服务的前提下开展的工作,对这样的"开放"应该有正确的解读,应该根据我国的实际情况讨论问题,应避免用不切实际的理论或理由来要求、评价这种开放。

关键词：高校图书馆开放文献利用率