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Science China Materials 2025年第1期68卷 65-85页

作者： Zeqi Wu feng niu Da Chen Yuexiang Huang Guigao Liu Yong Zhou Wenguang Tu Xi Zhu Zhigang Zou College of Materials and Chemistry China Jiliang UniversityHangzhou 310018China School of Science and Engineering The Chinese University of Hong Kong(Shenzhen)Shenzhen 518172China National Special Superfine Powder Engineering Research Center School of Chemistry and Chemical EngineeringNanjing University of Science and TechnologyNanjing 210094China Jiangsu Key Laboratory for Nano Technology National Laboratory of Solid State MicrostructuresCollaborative Innovation Center of Advanced MicrostructuresSchool of PhysicsNanjing UniversityNanjing 210093China

Phase transformation of two-dimensional(2D)nanomaterials can lead to significant changes in electronic and optical properties,which enables the development of novel *** strategies for phase engineering of 2D nanomaterials have drawn considerable attention in recent *** review focuses on the state-of-the-art progress in the phase transformation of 2D nanomaterials and their catalytic ***,the basic concepts of phase transformation and the outstanding electronic and optical properties induced by phase transformation are briefly ***,different strategies for achieving phase transformation are discussed in detail and classified into several types based on their characteristics,including(i)doping,(ii)external fields,(iii)optical irradiation,(iv)strain effect,(v)high-energy particle excitation,and(vi)thermal *** applications of 2D nanomaterials in catalysis based on phase transformation have also been ***,a summary of the technical challenges to phase control in 2D nanomaterials and potential opportunities for developing novel applications is presented.

关键词： phase transformation two-dimensional nanomaterials strategy catalysis application

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后全运时期陕西省体育场馆建设的策略研究

当代体育科技 2025年第1期15卷 95-97,102页

作者：牛峰西安交通大学城市学院陕西西安710018

十四届全运会的成功举办加速了陕西省体育场馆的建设进程。该文依托第十四届全运会留下的遗产与红利,深入分析了陕西省体育场馆建设的制约因素,并提出了相应的建设策略,旨在为后续的体育场馆建设提供有益的参考,进而推动陕西体育强省的... 详细信息

十四届全运会的成功举办加速了陕西省体育场馆的建设进程。该文依托第十四届全运会留下的遗产与红利,深入分析了陕西省体育场馆建设的制约因素,并提出了相应的建设策略,旨在为后续的体育场馆建设提供有益的参考,进而推动陕西体育强省的建设步伐。该文采用了文献资料法、专家访谈法、实地调查法和逻辑分析法等多种研究方法。研究结果显示:体育场馆建设中存在资源浪费的问题;体育场馆的选址与布局不尽合理;体育场馆建设的投资主体较为单一;体育场馆的设计功能较为单一。针对上述问题,该文提出以下建议:一是尽快全面贯彻落实相关法律法规,以有效避免资源浪费现象的发生;二是在土地使用方面应给予体育场馆建设更多的支持,确保选址合理、布局科学;三是加大政府财政投资力度,并积极吸引社会资本参与投资;四是大力培养体育复合型人才,以满足体育场馆建设和运营的多方面需求。

关键词：体育强省后全运时期体育场馆建设体育场馆经营

Strong Commutativity-preserving Generalized Derivations on Semiprime Rings

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Acta Mathematica Sinica,English Series 2008年第11期24卷 1835-1842页

作者： Jing MA Xiao Wei XU feng Wen niu Institute of Mathematics Jilin University Changchun 130012 P. R. China Department of Mathematics Shandong University Jinan 250100 P. R. China

Let R be a ring with a subset S. A mapping of R into itself is called strong commutativitypreserving （scp） on S, if [f（x）, f（y）] = [x, y] for all x, y ∈ S. The main purpose of this paper is to describe the structure of the generalized derivations which are scp on some ideals and right ideals of a prime ring, respectively. The semiprime case is also considered.

关键词： (semi-)prime ring generalized derivation GPI strong commutativity-preserving

A novel thyristor-based hybrid DC circuit breaker with short arcing capability

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High Voltage 2024年第6期9卷 1288-1301页

作者： Guanlong Jia Yuchen Yuan Hongjiang Guo Xiaoxue Wang feng niu Key Laboratory of Electromagnetic Field and Electrical Apparatus Reliability of Hebei Province School of Electrical EngineeringHebei University of TechnologyTianjinChina

Multi-terminal flexible high-voltage direct current(HVDC)transmission and DC grid technology are developing *** hybrid DC circuit breaker(HCB)has broad application prospects in the field of HVDC transmission and DC power ***-theless,existing HCBs have one or more following blemishes:arc suppression scheme of mechanical switch,high cost and unreliable adaptive *** this paper,a modified thyristor-based hybrid DC circuit breaker with short arcing capacity(SA-HCB)is introduced,which consists of the main branch,the fault handling branch and the pre-charging ***,the modified SA-HCB has the inherent capability of adaptive *** advantages of thyristors are fully used in the SA-HCB,such as low cost,low conduction voltage drop,and natural *** detailed structure diagram and mathematical model of the SA-HCB are introduced,and the operation processes of the fault current transfer are also ***,a design method for parameters of the proposed SA-HCB is ***,a single-ended equivalent system is built in PSCAD/EMTDC to verify the accuracy of the theoretical analysis and parameter ***,based on four-terminal simulation,the economy of the SA-HCB is verified by comparing with the topology proposed by ***,the small-scale experiment of the proposed SA-HCB is introduced.

关键词： PSCAD/EMTDC branch fault

Sensorless Control of Permanent Magnet Synchronous Motor Based on New Sliding Mode Observer with Single Resistor Current Reconstruction

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CES Transactions on Electrical Machines and Systems 2022年第4期6卷 378-383页

作者： Qingguo Sun Xiaolei Zhu feng niu IEEE Hebei University of Technology

To solve the chattering problem caused by discontinuous switching function in traditional sliding mode observer,a piecewise square root switching function with continuously varying characteristics is designed,and its stability is analyzed by using Lyapunov stability ***,according to the relationship among bus current,switching state and phase current,a single bus resistance sampling current reconstruction scheme without current sensors is adopted,which effectively reduces the cost of motor ***,the feasibility and effectiveness of the proposed scheme are verified by simulation.

关键词： Permanent magnet synchronous motor New sliding mode observer Phase-locked loop Single resistor Current reconstruction

Characterization of Gallic Acid Interaction with Human Serum Albumin by Spectral and Molecular Modeling Methods

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Chemical Research in Chinese Universities 2012年第2期28卷 287-290页

作者： LIU Zuo-jia LI Dan niu feng-lan School of Public Health Jilin UniversityChangchun 130021P.R.China

The binding of drugs with human serum albumin（HSA） is a crucial factor influencing the distribution and bioactivity of drugs in the *** understand the action mechanisms between gallic acid（GA,3,4,5-trihydroxybenzoic acid） and HSA,the binding of GA with HSA was investigated by a combined experimental and computational *** fluorescence properties of HSA and the binding parameters of GA collectively indicate that the binding is characterized by static quenching mechanism at one high affinity binding *** to the estimated molecular distance between the donor（HSA） and the acceptor（GA）,the binding is related to the fluorescence resonance energy *** indicated by the thermodynamic parameters,hydrophobic interaction plays a major role in the GA-HSA ***,the experimental results reveal that GA is bound in the large hydrophobic cavity of subdomain IIA in the site I of HSA,which is well approved by molecular docking.

关键词： Gallic acid Human serum albumin Fluorescence quenching Molecular modeling

Study of electrospray ionization tandem mass spectrometry of the benzofuranone compounds

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Chinese Chemical Letters 2008年第3期19卷 324-328页

作者： Zhan Qi niu Yu Min Sun feng niu Jian Han Da Wei Chen School of Pharmacy of Shenyang Pharmaceutical University Shenyang 110016 China ShiJiaZhuang Pharnta Group NBP Pharmaceutical Co. Ltd. Shijiazhuang 052160 China Department of Pharmaceutical Engineering School of Chemical EngineeringDalian University of Technology Dalian 116000 China Department of Natural Medicines School of Pharmaceutical Sciences Peking Universio Health Science Center Beijing 10008.3 China

A detailed analysis of benzofuranone compounds under multiple tandem mass spectrometry （ESI-MS^n） conditions is reported. Element composition data of the fragment ions were obtained with the aid of comparison of the multiple tandem mass spectra of four compounds, and the structures of which are identical except for some substituted groups or epimers or cis-trans-isomers. Attempts have been made to provide rational pathways for the formation of the fragment ions from these protonated compounds. And the structure-fragmentation relationships will facilitate the characterization of the structures of other analogs.

关键词： ESI-MS^n Benzofuranones Epimer: cis-trans-Isomer

Master event based backazimuth estimation and its application to downhole microseismic monitoring

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Petroleum Science 2022年第6期19卷 2675-2682页

作者： Xiao-Bo Meng Hai-Chao Chen feng-Lin niu Yi-Jing Du Department of Geophysics Chengdu University of TechnologyChengduSichuan610059China Unconventional Petroleum Research Institute and State Key Laboratory of Petroleum Resources and ProspectingChina University of PetroleumBeijing102249China Department of Earth Environmental and Planetary SciencesRice UniversityHoustonTX77005USA Petro China Research Institute of Petroleum Exploration and Development Beijing100083China

Microseismic monitoring provides a valuable tool for evaluating the effectiveness of hydraulic fracturing ***,robust detection and accurate location of microseismic events are challenging due to the low signal to noise ratio(SNR)of their signals on *** a downhole monitoring setting,P-wave polarization direction measured from 3-component records is usually considered as the backazimuth of the microseismic event,i.e.,the direction of the *** direction and arrival time difference between the P and S waves is used to locate the seismic *** SNR is low,an accurate estimate of event backazimuth becomes very challenging with the traditional covariance matrix *** we propose to employ a master event and use a grid search method to find the backazimuth of a target event that maximizes the dot product of the two backazimuthal vectors of the master and target *** compared the backazimuths measured with the proposed grid-search and the conventional covariance-matrix methods using a large synthetic *** found that the grid-search method yields more accurate backazimuth estimates from low SNR records when measurements are made at single geophone *** array data are combined,the proposed method also has some advantage over the covariance-matrix method,especially when the number of geophones is *** also applied the method to a microseismic dataset acquired by a hydraulic fracturing project at a shale play site in southwestern China and found that the relocated microseismic events tend to align along existing faults more tightly than those in the original catalog.

关键词： Hydraulic fracturing Microseismic event Back azimuth Master event Grid search Covariance-matrix

Feasibility analysis of 60Co production in pressurized water reactors

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Nuclear Science and Techniques 2019年第10期30卷 21-29页

作者： Wei Zhang feng-Lei niu Ying Wu Zhang-Peng Guo Beijing Key Laboratory of Passive Safety Technology for Nuclear Energy North China Electric Power University

The radioactive isotope 60Co is used in many applications and is typically produced in heavy water *** most of the commercial reactors in operation are pressurized light water reactors(PWRs),the world supply of high level radioactive cobalt would be greatly increased if 60Co could be produced in ***,60Co production in PWRs has not been extensively studied;for the 59Co(n,c)60Co reaction,the positioning of 59Co rods in the reactor determines the rate of *** article primarily uses the models of 60Co production in Canadian CANDU power reactors and American boiling water reactors;based on relevant data from the pressurized water Daya Bay nuclear power plant,a PWR core model is constructed with the Monte Carlo N-Particle Transport Code;this model suggests changes to existing fuel assemblies to enhance 60Co *** addition,the plug rods are replaced with 59Co rods in the improved fuel assemblies in the simulation model to calculate critical parameters including the effective multiplication factor,neutron flux density,and distribution of energy *** considering different numbers of 59Co rods,the simulation indicates that different layout schemes have different impact levels,but the impact is not *** a whole,the components with four 59Co rods have a small impact,and the parameters of the reactor remain almost unchanged when four 59Co rods replace the secondary neutron ***,in theory,the use of a PWR to produce 60Co is feasible.

关键词： MCNP Fuel assembly Neutron flux Reactor power 60Co

Synthesis of the Biomimetic Polymer: Aliphatic Diamine and RGDS Modified Poly(d,l-lactic acid)

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Chinese Chemical Letters 2005年第8期16卷 1035-1038页

作者： Xu feng niu Yuan Liang WANG Yan feng LUO Jun PAN Li Xia GUO Key Lab of Biomechanics ＆ Tissue Engineering （Chongqing University） Ministry of Education Bioengineering College of Chongqing University Chongqing 400044

A novel poly（d, /-lactic acid）（PDLLA） based biomimetic polymer was synthesized by grafting maleic anhydride, butanediamine and arg-gly-asp-ser （RGDS） peptides onto the backbone of PDLLA, aiming to overcome the acidity and auto-accelerating degradation of PDLLA during degradation and to improve its biospecificity and biocompatibility. The synthetic copolymer was characterized by FTIR, ^13C NMR and amino acid analyzer （AAA）.

关键词： Poly(d,l-lactic acid) maleic anhydride butanediamine arg-gly-asp-ser modification.