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Potassium Acetate/18-Crown-6 Pair:Robust and Versatile Catalyst for Synthesis of Polyols from Ring-Opening Copolymerization of Epoxides and Cyclic Anhydrides

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Chinese Journal of Chemistry 2023年第1期41卷 83-92页

作者： Xiaoqing Dou Xiao-Hui liu Bin Wang yue-Sheng li School of Materials Science and Engineering Tiangong UniversityTianjin 300387China Tianjin Key Lab of Composite&Functional Materials School of Materials Science and EngineeringTianjin UniversityTianjin 300350China

Efficient synthesis of polyester polyols with tunable molecular weight and microstructures from cyclic anhydride/epoxide mixtures by taking advantage of chain transfer reaction remains a great challenge,because most of the catalysts exhibit poor tolerance to chain transfer agent(CTA).In this contribution,we demonstrated that potassium acetate(KOAc)and 18-crown-6(18-C-6)combination has great potential in the synthesis of diverse polyester polyols with controllable molecular weight and high-end group ***-pared with KOAc,KOAc/18-C-6 pair could induce a much faster chain transfer between the active and dormant chains,and thus produce polyester polyols with narrow and monomodal *** addition,polyester polyols could be efficiently prepared in laboratory by using commercially available cyclic anhydride without further purification(containing about 2%diacid residual as CTA)with an extremely low catalyst loading([catalyst pair]:[anhydride]:[epoxide]=1:50000:250000,[catalyst pair]=0.0004 mol%).KOAc/18-C-6 could also promote the self-switchable copolymerization of cyclic anhydride/epoxide/cyclic ester ***-opening copolymerization of cyclic ester was initiated automatically after the full conversion of cyclic anhydride,finally producing polyester polyols with ABA-type block structure.

关键词： Ring-opening polymerization Macrocyclic ligands Block copolymer Cyclic Anhydride Epoxide

Recent progress in synergistic electrocatalysis for generation of valuable products based on water cycle

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Nano Research 2023年第5期16卷 6444-6476页

作者： yue li Yanqing Jiao Haijing Yan Chungui Tian Aiping Wu Honggang Fu Key Laboratory of Functional Inorganic Material Chemistry Ministry of Education of the People’s Republic of China Heilongjiang UniversityHarbin 150080China

Given the grim situation of global warming and energy crisis,replacing traditional energy conversions based on carbon cycle with water cycle is a sustainable development *** synergistic electrocatalysis for value-added chemical production through oxygen species(O_(ads):OH^(*),O^(*),and OOH^(*))and the active hydrogen species(H_(ads))derived from water splitting powered by“green”electricity from renewable energy resource(wind,solar,etc.)is a promising manner,because of its reduced energy consumption and emission and high Faradaic *** study and summarization of catalytic mechanism of synergistic electrocatalysis are particularly significant,but are rarely *** this review,recent progress of various synergistic electrocatalysis systems for generating valuable products based on water cycle is systematically ***,the catalytic mechanism of synergistic electrocatalysis and the positive effect of O_(ads) and H_(ads) species produced by water splitting during the synergistic electrocatalytsis are detailedly ***,the regulation of water-derived O_(ads) and H_(ads) species for achieving efficient matchability of synergistic electrocatalysis is emphatically ***,we propose the limitations and future goals of this synergistic system based on water *** review is guidance for design of synergistic electrocatalysis architectures for producing valuable substances based on water cycle.

关键词： synergistic electrocatalysis water cycle active oxygen and hydrogen species valuable products

Ordered matrix representation supporting the visual analysis of associated data

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Science China(Information Sciences) 2020年第8期63卷 236-238页

作者： Yi CHEN Cheng LV yue li Wei CHEN Kwan-liu MA Beijing Key Laboratory of Big Data Technology for Food Safety Beijing Technology and Business University State Key Laboratory of CAD&CG Zhejiang University Department of Computer Science University of California

Associated data, which refer to sets of entities with specific relations and relational weights that can usually be expressed in a relational matrix, are found in many fields. Two typical examples are the pesticide residue dataset in food-safety, in which pesticides are associated with agricultural products [1], and E-transaction dataset, in which there is special relation between buyer and seller [2].However, on large data scales, finding the key en-

关键词： Visualization RW-Rank Ordered Matrix Associated Data Pesticide Residue Data

Omnidirectional Antenna Diversity System for High-Speed Onboard Communication

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Engineering 2022年第4期8卷 72-79页

作者： Yongjian Zhang yue li Weiquan Zhang Zhijun Zhang Zhenghe Feng Department of Electronic Engineering Tsinghua UniversityBeijing 100084China Beijing National Research Center for Information Science and Technology Tsinghua UniversityBeijing 100084China

In this article,an omnidirectional dual-polarized antenna with synergetic electromagnetic and aerodynamic properties is propounded for high-speed diversity *** propounded antenna comprises a probe-fed cavity for horizontally polarized radiation and a microstrip-fed slot for vertical ***-layer metasurfaces are properly designed as artificial magnetic conductor boundaries with direct metal-mountable onboard installation and compact *** attached wedge-shaped block is utilized for windage reduction in *** propounded antenna is fabricated for design verification,and the experimental results agree well with the simulated *** vertical polarization,the operating bandwidth is in the range of 2.37–2.55 GHz,and the realized gain variation in the azimuthal radiation pattern is 3.67 decibels(dB).While an impedance bandwidth in the range of 2.45–2.47 GHz and a gain variation of 3.71 dB are also achieved for horizontal polarization.A port isolation more than 33 dB is obtained in a compact volume of 0.247λ_(0)×0.345λ_(0)×0.074λ_(0),whereλ_(0)represents the wavelength in vacuum at the center frequency,wherein the wedge-shaped block is *** propounded diversity antenna has electromagnetic and aerodynamic merits,and exhibits an excellent potential for high-speed onboard communication.

关键词： Antenna diversity system Aerodynamics Electromagnetics Omnidirectional radiation High-speed onboard communication

New horizons for therapeutic applications of nanozymes in oral infection

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Particuology 2023年第9期80卷 61-73页

作者： Yanting Cai yue li Jin Zhang Nan Tang Xingfu Bao Zhen liu Department of Orthodontics Jilin Provincial Key Laboratory of Tooth Development and Bone RemodelingSchool and Hospital of StomatologyJilinUniversityChangchun130021China Beijing Advanced Innovation Center for Soft Matter Science and Engineering College of Life Science and TechnologyBeijing University of ChemicalTechnologyBeijing100029China

As a category of nanomaterials with excellent catalytic efficiency,great substrate specificity,and highrecovery efficiency,nanozymes have attracted increasing attention in various biomedical ***,numbers of nanozyme-assisted strategies have been well developed for the theranostics ofvarious diseases by taking advantages of their multienzyme-like characteristics,low cost,and *** the most prevalent oral diseases,oral infection poses a global hazard to human health,andcurrent therapeutic options are insufficient to resolve all the clinical *** on their admirableactivity,nanozymes can be frequently employed in the identification and treatment of various oral infectious ***,we provide a brief review focused on the classification of nanozymes,analysesof nanozyme-based antibacterial mechanism,research progress in oral bacterial control,and representative studies of nanozyme-assisted oral inflammatory ***,major challenges andpotential opportunities regarding the use of nanozymes in oral infectious diseases are also highlightedand *** review not only summarizes the recent studies of nanozymes in oral infection butalso promotes the further development of enzyme-mimetic strategies towards various oral diseases.

关键词： Nanozymes Oral infection Antibacterial therapy Anti-inflammatory therapy

Effects of combustion temperature on the optical properties of brown carbon from biomass burning

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Journal of Environmental Sciences 2024年第3期137卷 302-309页

作者： Peng Gao Rule Deng Song Jia yue li Xuefei Wang Qian Xing School of Chemistry Sciences University of Chinese Academy of SciencesBeijing 100049China College of Chemistry and Materials Engineering Beijing Technology and Business UniversityBeijing 100048China

Biomass burning has been known as one of main sources of Brown Carbon(BrC)in *** this study,by controlling the combustion temperature at 250℃,350℃,and 450℃,the methanol soluble organic carbon(MSOC)and methanol insoluble carbon(MISC)from pine wood burning was collected by ***–Vis,excitation emission matrix(EEM),TEM and FTIR spectra were applied to investigate the properties of BrC *** MSOC at 250℃ and 350℃,all the spectral profiles of UV–Vis absorption and excitation emission matrix are almost the same,while the EEM of MSOC at 450℃ are different from that of the other *** MISC fuorescence was observed only in the case of 450℃.In the FTIR spectra,with the temperature increasing the peaks associated to the oxygen-contained functions was weakened,indicating the formation of the fuorophores with larger conjugated system,especially aromatic *** results show that biomass combustion at low temperature produces more oxygen-riched BrC,which possesses relatively lower light absorption,while at high temperature produces more aromatics hydrocarbons with relatively strong light *** results of this work are helpful to trace the source of brown carbon and optimize biomass energy utilization.

关键词： Biomass burning Combustion temperature Methanol-soluble brown carbon EEM Impinger

Quasi-topological electromagnetism:Dark energy,dyonic black holes,stable photon spheres and hidden electromagnetic duality

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Science China(Physics,Mechanics & Astronomy) 2020年第4期63卷 73-87页

作者： Hai-Shan liu Zhan-Feng Mai yue-Zhou li H.Lu Center for Joint Quantum Studies and Department of Physics Tianjin UniversityTianjin 300350China Institute for Advanced Physics&Mathematics Zhejiang University of TechnologyHangzhou 310023China

We introduce the quasi-topological electromagnetism which is defined to be the squared norm of the topological 4-form F ∧ F. A salient property is that its energy-momentum tensor is of the isotropic perfect fluid with the pressure being precisely the opposite to its energy density. It can thus provide a model for dark energy. We study its application in both black hole physics and *** quasi-topological term has no effect on the purely electric or magnetic Reissner-Nordstr o¨m black holes, the dyonic solution is however completely modified. We find that the dyonic black holes can have four real horizons. For suitable parameters, the black hole can admit as many as three photon spheres, with one being stable. Another intriguing property is that although the quasitopological term breaks the electromagnetic duality, the symmetry emerges in the on-shell action in the Wheeler-De Witt patch. In cosmology, we demonstrate that the quasi-topological term alone is equivalent to a cosmological constant, but the model provides a mechanism for the dark energy to couple with other types of matter. We present a concrete example of the quasi-topological electromagnetism coupled to a scalar field that admits the standard FLRW cosmological solutions.

关键词： quasi-topological electromagnetism dark energy black holes photon spheres electromagnetic duality

Functionalized periodic Au@MOFs nanoparticle arrays as biosensors for dual-channel detection through the complementary effect of SPR and diffraction peaks

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Nano Research 2017年第7期10卷 2257-2270页

作者： lifeng Hang Fei Zhou Dandan Men Huilin li Xinyang li Honghua Zhang Guangqiang liu Weiping Cai Cuncheng li yue li Key Lab of Materials Physics Anhui Key Lab of Nanomaterials and Nanotechnology Institute of Solid State Physics Chinese Academy of Sciences Hefei 230031 China University of Science and Technology of China Hefei 230026 China School of Chemistry and Chemical Engineering University ofJinan Jinan 250022 China

A facile and low-cost method to prepare periodic Au@metal-organic framework （MOF）（MIL-100（Fe）） nanoparticle arrays was developed. The arrays were fabricated in situ using monolayer colloidal crystals as templates, followed by Au deposition on substrates, and annealing. MIL-100（Fe） coatings were applied on the nanospheres using a simple solvent thermal process. The prepared periodic Au@MIL-100（Fe） nanoparticle （NP） arrays were characterized by two peaks in the visible spectra. The first peak represented the surface plasmon resonance （SPR） of the Au nanospheres, and the other peak, or the diffraction peak originated from the periodic structure in the NP array. After modification with 3-aminophenylboronic acid hemisulfate （PBA）, the Au@MIL-100（Fe） NP arrays exhibited sensitive responses to different glucose concentrations with good selectivity. These responses could be due to the strong interaction between PBA and glucose molecules. The diffraction peak was sensitive at low glucose concentrations （less than 12 mM）, whereas the SPR peak rapidly responded at high concentrations. The peaks thus demonstrated satisfactory complementary sensitivity for glucose detection in different concentration regions. These results can be used to develop a dual-channel biosensor. We also created a standard diagram, which can be used to efficiently monitor blood glucose levels. The proposed strategy can be extended to develop different dual-channel sensors using Au@MIL-100（Fe） NP arrays agents. functionalized with different recognition

关键词： Au nanosphere array Au@MIL-100(Fe) 3-aminophenylboronicacid hemisulfate glucose dual-channel detection

A geographical and operational deep graph convolutional approach for flight delay prediction

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Chinese Journal of Aeronautics 2023年第3期36卷 357-367页

作者： Kaiquan CAI yue li Yongwen ZHU Quan FANG Yang YANG Wenbo DU School of Electronic and Information Engineering Beihang UniversityBeijing 100191China Key Laboratory of National Airspace Technology Beijing 100085China National Lab of Pattern Recognition Institute of AutomationChinese Academy of SciencesBeijing 100190China Research Institute for Frontier Science Beihang UniversityBeijing 100191China

Flight delay prediction has attracted great interest in civil aviation community due to its significant role in airline planning,flight scheduling,airport operation,and passenger *** delay is affected by numerous factors and irregularly propagates in air transportation networks owing to flight connectivity,which brings critical challenges to accurate flight delay *** recent years,Graph Convolutional Networks(GCNs)have become popular in flight delay prediction due to the advantage in extracting complicated ***,most of the existing GCN-based methods have failed to effectively capture the spatial-temporal information in flight delay *** this paper,a Geographical and Operational Graph Convolutional Network(GOGCN)is proposed for multi-airport flight delay *** GOGCN is a GCN-based spatial-temporal model that improves node feature representation ability with geographical and operational spatial-temporal interactions in a ***,an operational aggregator is designed to extract global operational information based on the graph structure,while a geographical aggregator is developed to capture the similar nature among spatially close *** experiments on a real-world dataset demonstrate that the proposed approach outperforms the state-of-the-art methods with a satisfying accuracy improvement.

关键词： Flight delay prediction Flight operation pattern Geographical interactive information Graph neural network Spatial-temporal information