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Preparation and Microstructure of Nanosized GaN Crystals

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Chinese Physics Letters 1996年第6期13卷 444-446页

作者： YU San li hong-dong YANG Hai-bin li dong-mei SUN Hai-ping ZOU Guang-tian National Laboratory of Superhard Materials Jilin UniversityChangchun 130023

Gallium nitride crystals in nano-scale have been fabricated by dc arc plasma method using gallium and N_(2)+NH_(3) as starting *** electron microscope,selected area diffraction and x-ray diffraction investigation of the as-grown GaN crystals show that the well faceted crystals are single crystalline GaN in wurtzite structure having lattice constants a_(0)=3.18Åand c_(0)=5.18Å.

关键词： materials. GaN Crystal

Alloy as advanced catalysts for electrocatalysis:From materials design to applications

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Chinese Chemical Letters 2024年第6期35卷 104-122页

作者： Pingfan Zhang Shihuan hong Ning Song Zhonghui Han Fei Ge Gang Dai hongjun dong Chunmei li Advanced Chemical Engineering Laboratory of Green Materials and Energy of Jiangsu Province Institute of Green Chemistry and Chemical TechnologySchool of Chemistry and Chemical EngineeringJiangsu UniversityZhenjiang 212013China Daqo Group Co.Ltd. Zhenjiang 212221China Key Laboratory of Groundwater Resources and Environment Ministry of EducationJilin Provincial Key Laboratory of Water Resource and EnvironmentCollege of New Energy and EnvironmentJilin UniversityChangchun 130021China

With the deep integration of electrochemical research with energy,environment,catalysis,and other fields,more and more new electrochemical catalytic reactions have entered our research *** catalysts have recently emerged as a new type of nanomaterial due to the rapid development of kinetic controlled synthesis *** materials offer several advantages over monometallic catalysts,including larger element combinations,complex geometries,bifunctional sites,and reduced use of precious *** paper provides a review of alloy electrocatalysts that are designed and prepared specifically for electrocatalytic *** use of alloy materials in electrocatalyst design is also discussed,highlighting their widespread application in this ***,various synthesis methods and synthesis mechanisms are systematically *** that,by correlating the properties of materials with the structure,relevant strategies toward advanced alloy electrocatalysts including composition regulation,size,morphology,surface engineering,defect engineering,interface engineering and strain engineering are *** addition,the important electrocatalytic applications and mechanisms of alloy electrocatalysts are described and ***,the current challenges and prospects regarding the development of alloy nanomaterials are *** review serves as a springboard from a fundamental understanding of alloy structural dynamics to design and various applications of electrocatalysts,particularly in energy and environmental sustainability.

关键词： Alloy Nanomaterial Electrocatalyst Materials design Electrocatalysis

Rhizosphere microbes influence wogonoside accumulation in perennial Scutellaria baicalensis

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Pedosphere 2024年第3期34卷 553-566页

作者： Yang SUN hong liU Junwei PENG Minchong SHEN Yang HU dongsheng YU Jiangang li Yuanhua dong CAS Key Laboratory of Soil Environment and Pollution Remediation Institute of Soil ScienceChinese Academy of SciencesNanjing 210008(China) University of Chinese Academy of Sciences Beijing 100049(China) Tobacco Research Institute of Chinese Academy of Agricultural Sciences Qingdao 266101(China)

Dried roots of Scutellaria baicalensis Georgi are an acclaimed traditional Chinese medicine,and wogonoside content is a key indicator used to evaluate *** *** than rising linearly with cultivation years,*** quality initially increases and then ***,little is known regarding the dynamic variations in *** rhizosphere microorganisms under long-term cultivation and underlying mechanisms of their effects on wogonoside formation and *** aim of this study was to investigate the roles of soil nutrients and rhizosphere microbes on *** quality across different cultivation years(1-4 years).The wogonoside content(25.14 mg g^(-1))was highest in the biennial *** and then decreased following long-term *** soil nutrients(available nitrogen,available phosphorus,available iron,available manganese,and available zinc)were reduced significantly as cultivation years *** also affected rhizosphere bacterial community structure significantly,driving it toward deterministic process(i.e.,β-nearest taxon indexlity under long-term cultivation from the perspective of soil nutrients and microorganisms,which may theoretically support the future artificial cultivation and management of Chinese medicinal plants.

关键词： bacterial diversity medicinal plant rhizosphere bacterial community soil nutrient wogonoside content wogonoside formation

A Multi-Agent Immunology Model for Security Computer

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Wuhan University Journal of Natural Sciences 2001年第Z1期6卷 486-490页

作者： liang Yi wen, li Huan, Kang li shan, dong hong bin College of Computer Science, Wuhan University, Wuhan 430072, China College of Computer Science Wuhan University Wuhan China

This paper presents a computer immunology model for computer security, whose main components are defined as idea of Multi Agent. It introduces the natural immune system on the principle, discusses the idea and characteristics of Multi Agent. It gives a system model, and describes the structure and function of each agent. Also, the communication method between agents is described.

关键词： computer immunology multi agent computer security

Auto-parametric resonance of a continuous-beam-bridge model under two-point periodic excitation:an experimental investigation and stability analysis

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Earthquake Engineering and Engineering Vibration 2024年第2期23卷 445-454页

作者： li Yuchun Shen Chao liu Wei li dong Department of Hydraulic Engineering College of Civil EngineeringTongji UniversityShanghai 200092China

The auto-parametric resonance of a continuous-beam bridge model subjected to a two-point periodic excitation is experimentally and numerically investigated in this *** auto-parametric resonance experiment of the test model is conducted to observe and measure the auto-parametric resonance of a continuous beam under a two-point excitation on *** parametric vibration equation is established for the test model using the finite-element *** auto-parametric resonance stability of the structure is analyzed by using Newmark's method and the energy-growth exponent *** effects of the phase difference of the two-point excitation on the stability boundaries of auto-parametric resonance are studied for the test *** with the experiment,the numerical instability predictions of auto-parametric resonance are consistent with the test phenomena,and the numerical stability boundaries of auto-parametric resonance agree with the experimental *** a continuous beam bridge,when the ratio of multipoint excitation frequency(applied to the columns)to natural frequency of the continuous girder is approximately equal to 2,the continuous beam may undergo a strong auto-parametric *** with the present experiment and analysis,a hypothesis of Volgograd Bridge's serpentine vibration is discussed.

关键词： auto-parametric resonance continuous beam bridge model two-point excitation experimental investigation stability analysis vibration of Volgograd Bridge

State-Based Opacity Verification of Networked Discrete Event Systems Using Labeled Petri Nets

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IEEE/CAA Journal of Automatica Sinica 2024年第5期11卷 1274-1291页

作者： Yifan dong Naiqi Wu Zhiwu li The authors are with the Institute of Systems Engineering Macao University of Science and TechnologyTaipa 999078MacaoChina

The opaque property plays an important role in the operation of a security-critical system,implying that pre-defined secret information of the system is not able to be inferred through partially observing its *** paper addresses the verification of current-state,initial-state,infinite-step,and K-step opacity of networked discrete event systems modeled by labeled Petri nets,where communication losses and delays are *** on the symbolic technique for the representation of states in Petri nets,an observer and an estimator are designed for the verification of current-state and initial-state opacity,***,we propose a structure called an I-observer that is combined with secret states to verify whether a networked discrete event system is infinite-step opaque or K-step *** to the utilization of symbolic approaches for the state-based opacity verification,the computation of the reachability graphs of labeled Petri nets is avoided,which dramatically reduces the computational overheads stemming from networked discrete event systems.

关键词： infinite system symbolic

Carrimycin inhibits coronavirus replication by decreasing the efficiency of programmed–1 ribosomal frameshifting through directly binding to the RNA pseudoknot of viral frameshift-stimulatory element

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Acta Pharmaceutica Sinica B 2024年第6期14卷 2567-2580页

作者： hongying li Jianrui li Jiayu li Hu li Xuekai Wang Jing Jiang Lei Lei Han Sun Mei Tang Biao dong Weiqing He Shuyi Si Bin hong Yinghong li Danqing Song Zonggen Peng Yongsheng Che Jian-dong Jiang CAMS Key Laboratory of Antiviral Drug Research Institute of Medicinal BiotechnologyChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100050China Beijing Key Laboratory of Antimicrobial Agents Institute of Medicinal BiotechnologyChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100050China Key Laboratory of Biotechnology of Antibiotics the National Health and Family Planning Commission(NHFPC)Institute of Medicinal BiotechnologyChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100050China

The pandemic of SARS-CoV-2 worldwide with successive emerging variants urgently calls for small-molecule oral drugs with broad-spectrum antiviral ***,we show that carrimycin,a new macrolide antibiotic in the clinic and an antiviral candidate for SARS-CoV-2 in phase III trials,decreases the efficiency of programmed–1 ribosomal frameshifting of coronaviruses and thus impedes viral replication in a broad-spectrum *** binds directly to the coronaviral frameshift-stimulatory element(FSE)RNA pseudoknot,interrupting the viral protein translation switch from ORF1a to ORF1b and thereby reducing the level of the core components of the viral replication and transcription *** carrimycin with known viral replicase inhibitors yielded a synergistic inhibitory effect on *** the FSE mechanism is essential in all coronaviruses,carrimycin could be a new broad-spectrum antiviral drug for human coronaviruses by directly targeting the conserved coronaviral FSE *** finding may open a new direction in antiviral drug discovery for coronavirus variants.

关键词： Carrimycin Coronavirus Broad-spectrum antiviral activity Programmed-1 ribosomal frameshifting RNA pseudoknot Antiviral agent RNA target Synergistic inhibitory effect

Alloy/layer double hydroxide interphasic synergy via nano-heterointerfacing for highly reversible CO_(2)redox reaction in li-CO_(2)batteries

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Nano Research 2024年第6期17卷 5206-5215页

作者： Tianzhen Jian Wenqing Ma Jiagang Hou Jianping Ma Xianhong li Haiyang Gao Caixia Xu hong liu Institute for Advanced Interdisciplinary Research(iAIR) Collaborative Innovation Center of Technology and Equipment for Biological Diagnosis and Therapy in Universities of ShandongSchool of Chemistry and Chemical EngineeringUniversity of JinanJinan 250022China Kyiv College at Qilu University of Technology Qilu University of Technology(Shandong Academy of Sciences)Jinan 250353China State Key Laboratory of Crystal Materials Shandong UniversityJinan 250100China Shandong Sacred Sun Power Sources Co. Ltd.Qufu 273100China

li-CO_(2)batteries are among the most intriguing techniques for balancing the carbon cycle,but are challenged by the annoyed thermodynamic barrier of the li_(2)CO_(3)decomposition ***,we demonstrate the electrocatalytic performances of two-dimensional(2D)CoAl-layer double hydroxide(LDH)nanosheets can be significantly improved by trans-dimensional crosslinking with three-dimensional(3D)multilevel nanoporous(MP)-RuCoAl alloy(MP-RuCoAl alloy⊥CoAl-LDH).The MP-RuCoAl alloy⊥CoAl-LDH with multiscale pore channels and abundant nano-heterointerface is directly prepared by controllable etching Al from a Ru-Co-Al master alloy along with simultaneous partial oxidization of Al and Co *** MP-RuCoAl is composed of various intermetallic compounds and Ru with abundant grain boundaries,and forms numerous heterointerface with 2D CoAl-LDH *** multiscale porous metallic network benefits mass and electron transportation as well as discharge product storage and enables a rich multiphase reaction *** situ differential electrochemical mass spectrometry shows that the mass-to-charge ratio in the charging process is~0.733 which is consistent with the theoretical value of 3/4,stating that the reversible co-decomposition of li_(2)CO_(3)and C can be achieved with the MP-RuCoAl alloy⊥*** Ketjen black(KB)/MP-RuCoAl⊥CoAl-LDH battery demonstrates a high cyclability for over 2270 h(227 cycles)with a lower voltage gap stabilized at~1.3 V at 200 mA·g^(−1).Our findings here provide useful guidelines for developing high efficiency transition metal based electrocatalysts by coupling with conductive porous substrate for impelling the development of practical li-CO_(2)battery systems.

关键词： heterojunction interface nanoporous li-CO_(2)battery dealloying

Optimizing near-carbon-free nuclear energy systems:advances in reactor operation digital twin through hybrid machine learning algorithms for parameter identification and state estimation

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Nuclear Science and Techniques 2024年第8期35卷 177-203页

作者： li‑Zhan hong He‑lin Gong hong‑Jun Ji Jia‑liang Lu Han li Qing li Paris Elite Institute of Technology Shanghai Jiao Tong UniversityShanghai 200240China Science and Technology on Reactor System Design Technology Laboratory Nuclear Power Institute of ChinaChengdu 610041China

Accurate and efficient online parameter identification and state estimation are crucial for leveraging digital twin simulations to optimize the operation of near-carbon-free nuclear energy *** previous studies,we developed a reactor operation digital twin(RODT).However,non-differentiabilities and discontinuities arise when employing machine learning-based surrogate forward models,challenging traditional gradient-based inverse methods and their *** study investigated deterministic and metaheuristic algorithms and developed hybrid algorithms to address these *** efficient modular RODT software framework that incorporates these methods into its post-evaluation module is presented for comprehensive *** methods were rigorously assessed based on convergence profiles,stability with respect to noise,and computational *** numerical results show that the hybrid KNNLHS algorithm excels in real-time online applications,balancing accuracy and efficiency with a prediction error rate of only 1%and processing times of less than 0.1 ***,algorithms such as FSA,DE,and ADE,although slightly slower(approximately 1 s),demonstrated higher accuracy with a 0.3%relative L_2 error,which advances RODT methodologies to harness machine learning and system modeling for improved reactor monitoring,systematic diagnosis of off-normal events,and lifetime management *** developed modular software and novel optimization methods presented offer pathways to realize the full potential of RODT for transforming energy engineering practices.

关键词： Parameter identification State estimation Reactor operation digital twin Reduced order model Inverse problem