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Science Bulletin 2024年第11期69卷 1653-1659页

作者：姜斌 Adrien Bouhon 吴世巧孔泽霖林志康 robert-Jan Slager 蒋建华 Suzhou Institute for Advanced Research University of Science and Technology of ChinaSuzhou 215123China School of Physical Science and Technology&Collaborative Innovation Center of Suzhou Nano Science and Technology Soochow UniversitySuzhou 215006China TCM Group Cavendish LaboratoryUniversity of CambridgeCambridge CB30HEUK NORDITA Stockholm University and KTH Royal Institute of TechnologyStockholm SE-10691Sweden

Topological band theory has conventionally been concerned with the topology of bands around a single gap. Only recently non-Abelian topologies that thrive on involving multiple gaps were studied, unveiling a new horizon in topological physics beyond the conventional paradigm. Here, we report on the first experimental realization of a topological Euler insulator phase with unique meronic characterization in an acoustic metamaterial. We demonstrate that this topological phase has several nontrivial features:First, the system cannot be described by conventional topological band theory, but has a nontrivial Euler class that captures the unconventional geometry of the Bloch bands in the Brillouin ***, we uncover in theory and probe in experiments a meronic configuration of the bulk Bloch states for the first time. Third, using a detailed symmetry analysis, we show that the topological Euler insulator evolves from a non-Abelian topological semimetal phase via. the annihilation of Dirac points in pairs in one of the band gaps. With these nontrivial properties, we establish concretely an unconventional bulk-edge correspondence which is confirmed by directly measuring the edge states via. pump-probe techniques. Our work thus unveils a nontrivial topological Euler insulator phase with a unique meronic pattern and paves the way as a platform for non-Abelian topological phenomena.

关键词： Euler insulators Meronic waves Acoustic metamaterials Topological phases of matter

Hydrogen Peroxide Electrosynthesis in a Strong Acidic Environment Using Cationic Surfactants

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Precision Chemistry 2024年第4期2卷 129-137页

作者： Zachary Adler Xiao Zhang Guangxia Feng Yaping shi Peng Zhu Yang Xia Xiaonan Shan Haotian Wang Rice University Department of Chemical and Biomolecular EngineeringHoustonTexas 77005United States University of Houston Department of Electrical and Computer EngineeringHoustonTexas 77004United States

The two-electron oxygen reduction reaction(2e^(−)-ORR)can be exploited for green production of hydrogen peroxide(H_(2)O_(2)),but it still suffers from low selectivity in an acidic electrolyte when using non-noble metal ***,inspired by biology,we demonstrate a strategy that exploits the micellization of surfactant molecules to promote the H_(2)O_(2)selectivity of a low-cost carbon black catalyst in strong acid *** surfactants near the electrode surface increase the oxygen solubility and transportation,and they provide a shielding effect that displaces protons from the electric double layer(EDL).Compared with the case of a pure acidic electrolyte,we find that,when a small number of surfactant molecules were added to the acid,the H_(2)O_(2)Faradaic efficiency(FE)was improved from 12%to 95%H_(2)O_(2)under 200 mA cm^(−2),suggesting an 8-fold *** in situ surface enhanced Raman spectroscopy(SERS)and optical microscopy(OM)studies suggest that,while the added surfactant reduces the electrode’s hydrophobicity,its micelle formation could promote the O_(2) gas transport and its hydrophobic tail could displace local protons under applied negative potentials during catalysis,which are responsible for the improved H_(2)O_(2)selectivity in strong acids.

关键词： electrocatalysis hydrogen peroxide electrosynthesis oxygen reduction reaction interfacial engineering surfactant CTAB

学业·交游·转型:余光中与创意写作教育的接受

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湖北大学学报（哲学社会科学版） 2024年第5期51卷 98-106,F0003页

作者：宋时磊武汉大学汉语写作研究中心湖北武汉430072

1958—1959年,余光中到美国爱荷华大学创作班学习并获得艺术硕士学位,成为首位系统接受创意写作专业教育的中国作家,就此拉开了创意写作中国发展史的序幕。余光中的留学契机得益于多重背景和机缘,最终促成了此次美国之行。爱荷华大学创... 详细信息

1958—1959年,余光中到美国爱荷华大学创作班学习并获得艺术硕士学位,成为首位系统接受创意写作专业教育的中国作家,就此拉开了创意写作中国发展史的序幕。余光中的留学契机得益于多重背景和机缘,最终促成了此次美国之行。爱荷华大学创作班的学业促进了余光中的成长,与现代诗人弗罗斯特等人的交往成为其难忘记忆;他交游广泛,对现代主义文学艺术有了深刻理解,在美国的风景和文化现场中他开始反观中国。这一时期是余光中诗歌翻译事业的关键期,又是他散文写作的起步期。诗歌方面,他以美国留学的内心体验为素材写成诗集《万圣节》,这部诗集诠释了他现代主义的诗歌理念,标志着其诗歌艺术的提升,更重要的是余光中怀乡和乡愁的内涵发生转变,上升到依恋中国以及文化母体的层面。无论从个人发展和文学创作来审视,还是从创意写作教育中国接受史来衡量,余光中接受创意写作教育无疑是当代中国一个重要的文学和教育事件。

关键词：余光中创意写作爱荷华大学创作转型

New developments in Western blot technology

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Chinese Chemical Letters 2015年第4期26卷 416-418页

作者： shi Jin robert T.Kennedy Department of Chemistry University of Michigan

Western blotting is a highly valued method for protein identification and relative quantitation in complex samples. It combines size-based electrophoretic separation with immunoaffinity to identify specific proteins. This technique remains popular and has become a workhorse in biochemical research and clinical laboratories. Despite its utility and popularity, this method has many limitations including slow analysis, incompatibility with limited sample application, low throughput and low information content. Recently there has been significant success in improving different aspects of Western blotting. In this review, we provide an overview of the developments in the area of improving conventional Western blotting methods with a focus on recent developments in microfluidic Western blotting. We overview different separation platforms, and discuss studies on protein transfer methods as well as protein immobilization methods and chemistries. We also describe integrated miniaturized platforms that can perform rapid separations and immunodetections.

关键词： Western blotMicrofluidicGel electrophoresislmmunoassay

Highly enantioselective construction of CF_(3) -bearing all-carbon quaternary stereocenters: Chiral spiro-fused bisoxazoline ligands with 1,1'-binaphthyl sidearm for asymmetric Michael-type Friedel-Crafts reaction

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Chinese Chemical Letters 2022年第5期33卷 2415-2419页

作者： robert Li-Yuan Bao Lei shi Kang Fu School of Science Harbin Institute of TechnologyShenzhen 518055China State Key Laboratory of Elemento-Organic Chemistry Nankai UniversityTianjin 300071China Guangdong Provincial Key Laboratory of Catalysis Southern University of Science and TechnologyShenzhen 518055China School of Chemistry and Chemical Engineering Harbin Institute of TechnologyHarbin 150001China

A novel class of chiral spiro-fused bisoxazoline ligands possessing a deep chiral pocket was *** developed ligands have been employed in the nickel-catalyzed highly enantioselective Michael-type Friedel-Crafts reaction, affording the products bearing a trifluoromethylated all-carbon quaternary stereocenter with moderate to excellent yields(up to 99%) and good to excellent enantioselectivies(up to> 99.9% ee). Moreover, a proposed model of chiral pocket revealed that the attack of indole from the Re-face of β-CF_(3)-β-disubstituted nitroalkene was favorable.

关键词： Chiral bisoxazoline ligand Chiral pocket Chiral spiro ligand Friedel-Crafts reaction Trifluoromethylated all-carbon quaternary stereocenter

Mesoproterozoic biomineralization:Cyanobacterium-like filamentous siderite sheaths~1.4 Ga

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Journal of Palaeogeography 2023年第3期12卷 384-400页

作者： Dong-Jie Tang Xiao-Ying shi Xi-Qiang Zhou robert Riding State Key Laboratory of Biogeology and Environmental Geology China University of Geosciences(Beijing)Beijing 100083China Institute of Earth Sciences China University of Geosciences(Beijing)Beijing 100083China School of Earth Sciences and Resources China University of Geosciences(Beijing)Beijing 100083China Key Laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China Department of Earth and Planetary Sciences University of TennesseeKnoxvilleTN 37996-1526USA

Biomineralization was a key development in a wide variety of organisms,yet its history prior to the Ediacaran remains poorly *** this paper,we describe~1420-1330 million year old microscopic tubes preserved as siderite(FeCO_(3)).In size and shape these tubes closely resemble cyanobacterial sheaths forming mineralized *** consider two competing explanations for their ***,the tubes and associated sediment were originally composed of Ca-carbonate that was subsequently replaced by *** this case,siderite mineralization was early,but post-mortem,as in early silicification,and preferentially preserved the more resilient ***,no relict calcite is ***,the Fe-carbonate mineralogy of the tubes and sediment is *** this case,photosynthetic oxygen may have precipitated Fe-oxyhydroxide that was promptly converted to siderite by dissimilatory iron reduction(DIR).Primary siderite mineralization of cyanobacteria has not been described *** explanations link photosynthetic processes to preferential sheath mineralization during the life of the cyanobacteria,as observed in present-day calcified *** process might include CO_(2)-concentrating mechanisms(CCMs)linked to relatively low levels of atmospheric CO_(2),consistent with empirical estimates of mid-Proterozoic CO_(2)levels based on paleosols and weathering *** either case,these cyanobacterium-like fossils preserved in siderite provide an early example of biomineralization and suggest the interactive in-fluences of both metabolic processes and ambient seawater chemistry.

关键词： Xiamaling Formation Siderite Ferruginous Dissimilatory iron reduction(DIR) Iron formation(IF) CO_(2)-concentrating mechanism(CCM)

Detection and Classification of Transmission Line Transient Faults Based on Graph Convolutional Neural Network

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CSEE Journal of Power and Energy Systems 2021年第3期7卷 456-471页

作者： Houjie Tong robert C.Qiu Dongxia Zhang Haosen Yang Qi Ding Xin shi Department of Electrical Engineering Center for Big Data and Artificial IntelligenceShanghai Jiao Tong UniversityShanghai 200240China School of Electronic Information and Communication Huazhong University of Science and TechnologyWuhan 430000China Electric Power Research Institute Haidian DistrictBeijing 100192China School of Control and Computer Engineering North China Electric Power UniversityBeijing 102206China

We present a novel transient fault detection and classification approach in power transmission lines based on graph convolutional neural *** with the existing techniques,the proposed approach considers explicit spatial information in sampling sequences as prior knowledge and it has stronger feature extraction *** this basis,a framework for transient fault detection and classification is *** structure is generated to provide topology information to the *** approach takes the adjacency matrix of topology graph and the bus voltage signals during a sampling period after transient faults as inputs,and outputs the predicted classification results ***,the proposed approach is tested in various situations and its generalization ability is verified by experimental *** results show that the proposed approach can detect and classify transient faults more effectively than the existing techniques,and it is practical for online transmission line protection for its rapidness,high robustness and generalization ability.

关键词： Graph convolutional network(GCN) power transmission line fault detection and classification spatio-temporal data topology information

Testing allometric scaling relationships in plant roots

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Forest Ecosystems 2020年第4期7卷 770-780页

作者： Qiang Deng Zhiyou Yuan Xinrong shi T.Ryan Lock robert L.Kallenbach State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau Institute of Soil and Water ConservationChinese Academy of Sciences and Ministry of Water ResourcesYangling 712100ShaanxiChina. University of Chinese Academy of Sciences Beijing 100049China. Institute of Soil and Water Conservation Northwest A&F UniversityYangling 712100ShaanxiChina Division of Plant Sciences College of AgricultureFoodand Natural ResourcesUniversity of Missouri108 Waters HallColumbiaMO 65211USA.

Background:Metabolic scaling theory predicts that plant productivity and biomass are both ***,this theory has not yet been tested in plant ***:In this study,we tested how metabolic scaling occurs in plants using a comprehensive plant root dataset made up of 1016 observations from natural *** generated metabolic scaling exponents by logtransformation of root productivity versus ***:Results showed that the metabolic scaling exponents of fine root(2mm in diameter).Conclusions:We found isometric metabolic scaling in fine roots,a metabolically active organ similar to seedlings or *** findings also indicate a shift in metabolic scaling during plant ***,our study supports the absence of any unified single constant scaling exponent for metabolism-biomass relationships in terrestrial plants,especially for forests with woody species.

关键词： Allometry Biomass Metabolic scaling Plant roots Productivity

The Mechanochemical Release of Naphthalimide Fluorophores fromβ-Carbonate andβ-Carbamate Disulfide-Centered Polymers

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CCS Chemistry 2021年第11期3卷 2333-2344页

作者： Zhiyuan shi Qingchuan Song robert Göstl Andreas Herrmann DWI—Leibniz Institute for Interactive Materials Aachen 52056 Institute of Technical and Macromolecular Chemistry RWTH Aachen UniversityAachen 52074 Department I of Internal Medicine University Hospital of CologneCologne 50937 Zernike Institute for Advanced Materials University of Groningen9747 AG Groningen

The covalent attachment of cargo molecules(e.g.,drugs and fluorophores)inβ-position to a disulfide moiety through carbamate and carbonate bonds finds many applications in responsive release ***,we showed that the combination of this release process with polymer mechanochemistry-induced disulfide scission enabled the remote-controlled release of small molecule drugs and fluorophores from their inactive parent macromolecules using *** nature of the linker bond largely governed the subsequent release kinetics,an aspect that has not been investigated so *** compare the differences,we here employ disulfide-centered polymers releasing either hydroxyl-or amino-naphthalimides from their respectiveβ-carbonate or-carbamate linkers by forceinduced intramolecular 5-exo-trig *** present the synthesis,characterization,and cell imaging evaluation of three naphthalimides featuring colorimetric and green fluorescence turn-on upon release,allowing monitoring of the release *** believe that the insights gained from these experiments would advance the tailoring of release rates for force-induced pharmacotherapy.

关键词： mechanochemistry polymers drug delivery bioimaging sonopharmacology