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Chinese Journal of Mechanical Engineering 2017年第6期30卷 1285-1295页

作者： pan-pan Wang Qiang Yu yong-Jun Hu Chang-Xin Miao School of Electrical and Power Engineering ChinaUniversity of Mining and Technology Xuzhou 221116China

Current research in broken rotor bar （BRB） fault detection in induction motors is primarily focused on a high-frequency resolution analysis of the stator current. Compared with a discrete Fourier transformation, the parametric spectrum estimation technique has a higher frequency accuracy and resolution. However, the existing detection methods based on parametric spectrum estima- tion cannot realize online detection, owing to the large computational cost. To improve the efficiency of BRB fault detection, a new detection method based on the min-norm algorithm and least square estimation is proposed in this paper. First, the stator current is filtered using a band-pass filter and divided into short overlapped data windows. The min-norm algorithm is then applied to determine the fre- quencies of the fundamental and fault characteristic com- ponents with each overlapped data window. Next, based on the frequency values obtained, a model of the fault current signal is constructed. Subsequently, a linear least squares problem solved through singular value decomposition is designed to estimate the amplitudes and phases of the related components. Finally, the proposed method is applied to a simulated current and an actual motor, the results of which indicate that, not only parametric spectrum estimation technique.

关键词： Fault detection Broken rotor bars Min-norm Least squares method Induction motors

Some 3-adic congruences for binomial sums

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Science China Mathematics 2014年第4期57卷 711-718页

作者： zhanG yong pan Hao Department of Basic Course Nanjing Institute of Technology Department of Mathematics Nanjing University

We prove some 3-adic congruences for binomial sums,which were conjectured by Zhi-Wei *** example,for any integer m≡1（mod 3）and any positive integer n,we have v3（1/n ∑n-1X k=0 1/mk 2k/ k〉））≥min{3（n）,3（m-1）-1},where 3（n）denotes the 3-adic order of *** our proofs,we use several auxiliary combinatorial identities and a series converging to 0 over the 3-adic field.

关键词： 3-adic order binomial sum

Mineral transition and formation mechanism of calcium aluminate compounds in CaO-Al2O3-Na2O system during high-temperature sintering

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International Journal of Minerals,Metallurgy and Materials 2020年第7期27卷 924-932页

作者： Hai-yan Yu Xiao-lin pan yong-pan Tian Gan-feng Tu School of Metallurgy Northeastern UniversityShenyang 110819China

The mineral transition and formation mechanism of calcium aluminate compounds in CaO-Al2O3-Na2O system during the hightemperature sintering process were systematically investigated using DSC-TG,XRD,SEM-EDS,FTIR,and Raman spectra,and the crystal structure of Na4Ca3(AlO2)10 was also simulated by Material Studio *** results indicated that the minerals formed during the sintering process included Na4Ca3(AlO2)10,CaO·Al2O3,and 12 CaO·7 Al2O3,and the content of Na4Ca3(AlO2)10 could reach 92 wt%when sintered at 1200°C for 30 *** main formation stage of Na4Ca3(AlO2)10 occurred at temperatures from 970 to 1100°C,and the content could reach82 wt%when the reaction temperature increased to 1100°*** crystal system of Na4Ca3(AlO2)10 was tetragonal,and the cells preferred to grow along crystal planes(110)and(210).The formation of Na4Ca3(AlO2)10 was an exothermic reaction that followed a secondary reaction model,and its activation energy was 223.97 kJ/mol.

关键词： calcium aluminate sodium oxide crystal structure formation kinetics sintering

Performance comparison of different microbial DNA extraction methods on bird feces

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Avian Research 2021年第2期12卷 247-254页

作者： Xian Hou Shengkai pan Zhenzhen Lin Jiliang Xu Xiangjiang zhan School of Ecology and Nature Conservation Beijing Forestry UniversityBeijing 100083China Key Lab of Animal Ecology and Conservation Biology Institute of ZoologyChinese Academy of SciencesBeijing 100101China Cardiff University-Institute of Zoology Joint Laboratory for Biocomplex-ity Research Chinese Academy of SciencesBeijing 100101China Center for Excellence in Animal Evolution and Genetics Chinese Academy of Sci-encesKunming 650223China

Background:As an important player during food digestion,gut microbiota has attracted much attention in diet adaptation studies in *** extracted from feces has been widely used as a proxy for gut *** several methods have been developed for microbial DNA extraction,their performances in the bird feces have not been systematacially evaluated ***:In this study,we applied three DNA extraction methods(Qiagen,MoBio and Bead)to extract DNA from feces of three avian dietary guilds(granivore,omnivore and carnivore),sequenced V4 region of 16S rRNA gene for each extract and evaluated the performances of DNA yield,DNA integrity,microbial composition,cell lysis capacity and alpha diversity for the three methods on each dietary ***:Bead method was the best on the performance of both DNA yield and DNA integrity regardless of dietary *** granivore,microbial relative abundance at both species and phylum levels,alpha diversity and cell lysis capacity were comparable among all *** omnivore,Qiagen had the best performance on alpha diversity,fol-lowed by Bead and *** were small variations on microbial relative abundance at both species and phylum levels among different extraction *** exhibited the best performance on cell lysis *** carnivore,considerable variations were found on microbial relative abundance at both species and phylum *** had the best performance on alpha diversity,followed by MoBio and *** had the highest cell lysis ***:DNA yield and integrity have no obvious impact on microbial composition,alpha diversity or cell lysis *** microbiota results(e.g.,microbial composition,cell lysis capacity,alpha diversity)obtained from differ-ent methods are comparable in granivorous avian species but not in omnivorous or carnivorous *** method could be used in granivore microbiota *** omnivores and carnivores,we recommend Qiagen method when the

关键词： 16S rRNA Alpha diversity Avian Dietary guild Feces DNA extraction method Microbial relative abundance

Strategies to enhance Li^(+) transference number in liquid electrolytes for better lithium batteries

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Nano Research 2023年第6期16卷 8055-8071页

作者： pan Zhou Xiaokun zhang yong Xiang Kai Liu Department of Chemical Engineering Tsinghua UniversityBeijing 100084China School of Materials and Energy University of Electronic Science and Technology of ChinaChengdu 611731China Advanced Energy Research Institute University of Electronic Science and Technology of ChinaChengdu 611731China Sichuan Provincial Engineering Research Center of Flexible Display Material Genome University of Electronic Science and Technology of ChinaChengdu 611731China

Growing market demand from portable electronics to electric automobiles boosts the development of lithium-ion batteries(LIBs)with high energy density and rate ***,strong solvation effect between lithium ions(Li^(+))and solvent molecules in common electrolytes limits the mobility of Li^(+)ions in ***,anions dominate the charge conduction in electrolytes,and in most cases,the value of Li^(+)transference number(T_(+))is between 0.2 and 0.4.A low T_(+)will aggravate concentration polarization in the process of charging and discharging,especially at high rate,which not only increases the overpotential but also intensifies side reactions,along with uneven deposition of lithium(Li)and the growth of lithium dendrites when lithium metal is used as *** this review,promising strategies to improve T_(+)in liquid electrolytes would be *** migration of Li^(+)ions is affected directly by the types and concentration of lithium salts,solvents,and additives in bulk ***,Li^(+)ions will pass through the separator and solid electrolyte interphase(SEI)when transferring between anodes and *** this in mind,we will classify and summarize threads of enhancing T_(+)from five aspects:lithium salts,solvents,additives,separators,and SEI based on different mechanisms,including covalently bonding,desolvation effect,Lewis acid-base interaction,electrostatic interaction,pore sieving,and supramolecular *** believe this review will present a systematic understanding and summary on T_(+)and point out some feasible threads to enhance battery performance by enhancing T_(+).

关键词： lithium batteries Li^(+)transference number rate performance strategies mechanisms

Analysis of infrared spectra with narrow band absorption by a graphene/square-ring structure

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Science China(Technological Sciences) 2020年第4期63卷 648-654页

作者： pan QingHui ZHOU SiHong SHUAI yong TAN HePing School of Energy Science of Engineering Harbin Institute of TechnologyHarbin 150001China

A graphene covered on square-ring structure is designed and fabricated to achieve narrow band absorption of three peaks in the infrared *** absorption rates of graphene/square-ring structures calculated by simulation are 90.49%,65.67%and 20.38%,respectively,and the experimentally measured absorption rates are 82.12%,53.13%,and 16.58%,*** the absorption rate of simulation calculation with experimental measurement,as well as the reasons for the differences are *** dynamic control characteristics of the graphene device are not observed with this structure in the experiment,which is different from the *** analyzed the reason for this distinction and proposed three solutions based on the experimental *** research results of this paper provide an important reference to the design and preparation of graphene devices.

关键词： graphene CVD infrared spectroscopy absorption

A review on current development of thermophotovoltaic technology in heat recovery

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International Journal of Extreme Manufacturing 2024年第2期6卷 297-323页

作者： Shuni Chen Yanming Guo Qinghui pan yong Shuai Ministry of Industry and Information Technology Key Laboratory of Aerospace Thermophysics School of Energy Science and EngineeringHarbin Institute of TechnologyHarbin 150001People’s Republic of China

The burning of fossil fuels in industry results in significant carbon emissions,and the heat generated is often not fully *** high-temperature industries,thermophotovoltaics(TPVs)is an effective method for waste heat *** review covers two aspects of high-efficiency TPV systems and industrial waste heat *** the system level,representative results of TPV complete the systems,while selective emitters and photovoltaic cells in the last decade are *** key points of components to improve the energy conversion efficiency are further analyzed,and the related micro/nano-fabrication methods are *** the application level,the feasibility of TPV applications in high-temperature industries is shown from the world waste heat utilization *** potential of TPV in waste heat recovery and carbon neutrality is illustrated with the steel industry as an example.

关键词： thermophotovoltaic waste heat recovery micro/nano-fabrication carbon neutrality

Characterization of blueberry exosome-like nanoparticles and miRNAs with potential cross-kingdom human gene targets

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Food Science and Human Wellness 2024年第2期13卷 869-878页

作者： Yangfan Leng Liubin Yang Siyi pan Leilei zhan Fang Yuan College of Food Science and Technology Huazhong Agricultural UniversityWuhan 430070China Hubei Key Laboratory of Fruit&Vegetable Processing&Quality Control Huazhong Agricultural UniversityWuhan 430070China Wuhan GeneCreate Biological Engineering Co. Ltd.Wuhan 430070China

Edible plant derived exosome-like nanoparticles(ELNs)have been shown to have multiple nutraceutical ***,the diversity of plant materials makes the plant derived ELN study *** efforts are still needed to explore the feasible isolation methods of edible plant derived ELNs and the possible roles of food-derived ELNs in improving human *** this study,a size exclusion chromatography based method was compared with the traditional ultracentrifugation method to isolate blueberry derived ELNs(B-ELNs),and the miRNA profile of B-ELNs was analyzed by high-throughput sequencing.A total of 36 miRNAs were found to be enriched in B-ELNs compared with berry tissue,and their potential cross-kingdom human gene targets were further *** showed that size exclusion chromatography was effective for B-ELN *** most abundant miRNAs in B-ELNs mainly belonged to the miR166 family and miR396 *** gene prediction indicated that B-ELNs could potentially regulate pathways related to the human digestive system,immune system and infectious diseases.

关键词： Edible plant derived exosomes-like nanoparticles Size exclusion chromatography miRNA Target gene prediction Blueberry

Finite-time fault-tolerant control of teleoperating cyber physical system against faults

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Journal of Systems Engineering and Electronics 2023年第2期34卷 469-478页

作者： pan Chengwei LIU Xia CHEN yong LI Meng School of Automation Engineering University of Electronic Science and Technology of ChinaChengdu 611731China Institute of Electric Vehicle Driving System and Safety Technology University of Electronic Science and Technology of ChinaChengdu 611731China School of Electrical Engineering and Electronic Information Xihua UniversityChengdu 610039China

This paper studies a finite-time adaptive fractionalorder fault-tolerant control(FTC)scheme for the slave position tracking of the teleoperating cyber physical system(TCPS)with external disturbances and actuator *** on the fractional Lyapunov stability theory and the finite-time stability theory,a fractional-order nonsingular fast terminal sliding mode(FONFTSM)control law is proposed to promote the tracking and fault tolerance performance of the considered ***,the adaptive fractional-order update laws are designed to cope with the unknown upper bounds of the unknown actuator faults and external ***,the finite-time stability of the closed-loop system is ***,comparison simulation results are also provided to show the validity and the advantages of the proposed techniques.

关键词： teleoperating cyber physical system(TCPS) fractional Lyapunov stability fault-tolerant control(FTC) finite-time stability

A REF6-dependent H3K27me3-depleted state facilitates gene activation during germination in Arabidopsis

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Journal of Genetics and Genomics 2023年第3期50卷 178-191页

作者： Jie pan Huairen zhang Zhenping zhan Ting Zhao Danhua Jiang State Key Laboratory of Plant Genomics Institute of Genetics and Developmental BiologyThe Innovative Academy for Seed DesignChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

Seed germination is a critical developmental switch from a quiescent state to active growth,which involves extensive changes in metabolism,gene expression,and cellular ***,our understanding of epigenetic and transcriptional reprogramming during this process is *** histone H3 lysine 27 trimethylation(H3K27me3)plays a key role in regulating gene repression and cell fate ***,we profile H3K27me3 dynamics and dissect the function of H3K27 demethylation during germination in *** temporal genome-wide profiling of H3K27me3 and transcription reveals delayed H3K27me3reprogramming compared with transcriptomic changes during germination,with H3K27me3 changes mainly occurring when the embryo is entering into vegetative *** OF EARLY FLOWERING 6(REF6)-mediated H3K27 demethylation is necessary for robust germination but does not significantly contribute to H3K27me3 dynamics during germination,but rather stably establishes an H3K27me3-depleted state that facilitates the activation of hormone-related and expansin-coding genes important for *** also show that the REF6 chromatin occupancy is gradually established during germination to counteract increased Polycomb repressive complex 2(PRC2).Our study provides key insights into the H3K27me3 dynamics during germination and suggests the function of H3K27me3 in facilitating cell fate ***,we reveal the importance of H3K27 demethylation-established transcriptional competence in gene activation during germination and likely other developmental processes.

关键词： H3K27me3 Epigenetic reprogramming H3K27 demethylation REF6 Germination Arabidopsis thaliana