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Journal of Materials Science & Technology 2021年第25期84卷 16-26页

作者： Z.w.Yang J.M.Lin J.F.Zhang q.w.qiu Y.wang D.P.wang J.Song Tianjin Key Lab of Advanced Joining Technology School of Materials Science and EngineeringTianjin UniversityTianjin300072China Department of Mining and Materials Engineering McGill UniversityMontréalQuébecH3A 0C5Canada

A novel method of liquid metallic film(LMF)bonding was developed to join titanium zirconium molybdenum alloy(TZM)and Nb-Zr alloy with a Ni *** this method,a Ni-Zr liquid phase was formed by the eutectic reaction and then squeezed out from the gap due to a transient pressure,leaving an *** not only achieved a reliable metallurgical bonding but also served as a transition layer between TZM and Nb-Zr alloy to reduce the mismatch between them thus further improving its *** bonding mechanism of the TZM and Nb-Zr system was discussed based on theoretical calculation and high-resolution microscopy *** advantages of this method were established by comparing the microstructure and mechanical properties of LMF bonded joints with that of traditional contact-reaction brazing and direct diffusion ***,the feasibility of the LMF bonding method was also demonstrated by the reliable joining of other high-temperature and immiscible systems.

关键词： Bonding Titanium zirconium molybdenum alloy(TZM) Diffusion Microstructure Mechanical properties

Implicit Function Based Open-loop Analysis Method for Detecting the SSR Using Identified System Parameters

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CSEE Journal of Power and Energy Systems 2024年第5期10卷 2016-2026页

作者： Luonan qiu Tianhao wen Yang Liu q.H.wu School of Electric Power Engineering South China University of TechnologyGuangzhou 510640China

This paper proposes an implicit function based open-loop analysis method to detect the subsynchronous resonance(SSR),including asymmetric subsynchronous modal attraction(ASSMA)and asymmetric subsynchronous modal repulsion(ASSMR),of doubly-fed induction generator based wind farms(DFIG-wFs)penetrated power *** some important parameters of DFIG-wF are difficult to obtain,reinforcement learning and least squares method are applied to identify those important *** predicting the location of closed-loop subsynchronous oscillation(SSO)modes based on the calculation of partial differentials of characteristic equation,both ASSMA and ASSMR can be *** proposed method in this paper can select SSO modes which move to the right half complex planes as control parameters ***,the proposed open-loop analysis method is adaptive to parameter *** studies are carried out on the 4-machine 11-bus power system to verify properties of the proposed method.

关键词： Open-loop modal analysis reinforcement learning based parameter identification subsynchronous resonance

Residue Based Open-Loop Modal Analysis Method for Detecting LFMR of PMSG-wFs Penetrated Power Systems

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CSEE Journal of Power and Energy Systems 2024年第4期10卷 1454-1465页

作者： Luonan qiu Tianhao wen Yang Liu q.H.wu School of Electric Power Engineering South China University of TechnologyGuangzhou510640China

This paper proposes a residue based open-loop modal analysis method to detect low frequency modal resonance(LFMR),including asymmetric low frequency modal attraction(ALFMA)and asymmetric low frequency modal repulsion(ALFMR),of permanent magnetic synchronous generator based wind farms(PMSG-wFs)penetrated power *** formation of ALFMA and ALFMR caused by two open-loop low frequency oscillation(LFO)modes moving close and apart is analyzed in *** predicting the trajectories of closed-loop LFO modes based on calculation of residue of open-loop LFO modes,both ALFMA and ALFMR can be *** proposed method can select LFO modes which move to the right half complex plane as control parameters *** studies are carried out on a three-machine power system and a four-machine 11-bus power system to verify the properties of the proposed method.

关键词： Asymmetric low frequency modal attraction asymmetric low frequency modal repulsion low frequency modal resonance residue based open-loop modal analysis method

The joint Laplace transforms for killed diffusion occupation times

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Applied Mathematics(A Journal of Chinese Universities) 2024年第3期39卷 398-415页

作者： LI Ying-qiu CHEN Ye School of Mathematics and Statistics Changsha University of Science and TechnologyChangsha 410114China College of Mathematics and Computational Science Hunan University of Arts and ScienceChangde 415000China

The approach of Li and Zhou(2014)is adopted to find the Laplace transform of occupation time over interval(0,a)and joint occupation times over semi-infinite intervals(-∞,a)and(b,∞)for a time-homogeneous diffusion process up to an independent exponential time e_(q)for 0quations associated with the diffusion *** these results,we obtain explicit expressions on the Laplace transform of occupation time and joint occupation time for Brownian motion with drift.

关键词： time-homogeneous diffusion process occupation time joint occupation time Laplace transform Brownian motion with drift

Tensor perturbations from bounce inflation scenario in f(q)gravity

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Science China(Physics,Mechanics & Astronomy) 2024年第2期67卷 78-92页

作者： Kun Hu Tanmoy Paul Taotao qiu Institute of Astrophysics Central China Normal UniversityWuhan 430079China School of Physics Huazhong University of Science and TechnologyWuhan 430074China National Institute of Technology Jamshedpur Department of PhysicsJamshedpur 831014India

In this paper,we construct a bounce inflation cosmological scenario in the framework of the modified symmetric teleparallel gravity,namely f(q)theory,and investigate the tensor perturbations *** is well-known,the tensor perturbations generated in the very early Universe(inflation and pre-inflation regions)can account for the primordial gravitational waves(PGws)that are to be detected by the next generation of Gw *** discuss the stability condition of the tensor perturbations in the bounce inflation process and investigate in detail the evolution of the perturbation *** general form of the tensor power spectrum is obtained both for large as well as small scale *** a result,we show both kinds of modes(short or long wavelength modes),and the tensor spectrum may get a positive tilt in the parametric range where the tensor perturbation proves to be stable—this interestingly hints an enhancement of gravitational waves’amplitude in the background of the f(q)bounce-inflation ***,we study the LqC-like scenario as a specific case of our model,in which,the primordial tensor power spectrum turns out to be nearly scale-invariant on both small and large scales.

关键词： bounce cosmology modified gravity cosmological perturbations

Constraining the Earth-mass Primordial Black Hole Mergers Model of the Non-repeating FRBs Using the First CHIME/FRB Catalog

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Research in Astronomy and Astrophysics 2024年第9期24卷 76-82页

作者： Min Meng qiu-Ju Huang Can-Min Deng Guangxi Key Laboratory for Relativistic Astrophysics School of Physical Science and TechnologyGuangxi UniversityNanning 530004China

In this paper,we upgrade the constraints for the Earth-mass primordial black hole mergers model based on the first Canadian Hydrogen Intensity Mapping Experiment(CHIME)/fast radio burst(FRB)*** the null hypothesis that the observed non-repeating FRBs originate from Earth-mass primordial black hole mergers,we find that how the charges were distributed in the primordial black hole population is well described by a double powerlaw function with typical charge value of law function with typical charge value of q_(c)/10^(-5)=1.60_(-0.28)^(+0.28),where the power-law index α_(1)=2.33_(-0.18)^(+0.15) for qq_(c) and α_(2)=4.56_(-0.26)^(+0.30)for q≥q_(c).Here,q represents the charge of the black hole in units of√GM,where M is the mass of the black ***,we infer the local event rate of the bursts is 8.8_(-2.1)^(+5.7)×10^(4)Gpc^(-3) yr^(-1),which indicates that an abundance of the primordial black hole population f■10^(-4) is needed to account for the observed FRBs by *** results of this paper lay the basis for further research on the electromagnetic radiation background generated by the merger of primordial black hole mergers.

关键词： black hole physics (stars:)gamma ray burst:general (cosmology:)dark matter

Effect on serum metabolomics of rats with premature ovarian insufficiency by Zhibian(BL54) through Shuidao(ST28) acupuncture

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Journal of Traditional Chinese Medicine 2024年第4期44卷 722-733页

作者： YAN Jing FENG Huimin qiu Fang wANG Haijun YIN Luyun JIN Xiaofei ZHAO Jiyu wANG Hongyang YAN Xiaoqin Second Clinical College of Shanxi University of Traditional Chinese Medicine Jinzhong 030619China Research Center of Experimental Acupuncture Science Tianjin University of Traditional Chinese MedicineTianjin 301617China Department of Cervical and Lumbar Vertebral Diseases Jinzhong Hospital Affiliated to Shanxi University of Traditional Chinese MedicineJinzhong 030600China

OBJECTIVE:To analyze the serum metabolic targets of the"Zhibian(BL54)through Shuidao(ST28)"acupuncture technique in cyclophosphamide(CTX)-induced premature ovarian insufficiency(POI)model rats and to elucidate the potential molecular mechanism of acupuncture in improving ***:we used an intraperitoneal injection of CTX to establish the POI rat model(POI group)and compared serum hormone levels and ovarian histopathological changes to evaluate the effect of the Zhibian(BL54)through Shuidao(ST28)technique(ZS+POI group)on ovarian ***,nontargeted metabolomics was performed using rat serum by ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry(UPLC-q-TOF/MS).RESULTS:After acupuncture intervention,the serum hormone levels and ovarian pathological morphology of POI rats were effectively ***,UPLC-q-TOF/MS results showed that the ZS+POI group showed a significant reversal of the levels of 6 differential *** them,the levels of four serum metabolic markers,divanillyltetrahydrofuran ferulate,trans-ferulic acid,tryptamine,and neuraminic acid,increased *** analysis of biological effects showed that all metabolites were involved in the regulation of reproductive hormone levels and antioxidant and antiapoptotic ***:The"Zhibian(BL54)through Shuidao(ST28)"acupuncture method may improve the ovarian function of POI rats by regulating serum metabolite markers to exert antioxidant and antiapoptotic effects,which provides a theoretical basis for the clinical application of acupuncture in the treatment of POI.

关键词： acupuncture premature ovarian insufficiency metabolomics ultra-performance liquid chromatography-quadrupole time-of-flight mass spectrometry Zhibian(BL54)through Shuidao(ST28)

Design of antiviral AGO2-dependent short hairpin RNAs

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Virologica Sinica 2024年第4期39卷 645-654页

作者： Yuanyuan Bie Jieling Zhang Jiyao Chen Yumin Zhang Muhan Huang Leike Zhang Xi Zhou Yang qiu Key Laboratory of Virology and Biosafety Wuhan Institute of VirologyChinese Academy of SciencesWuhan 430071China State Key Laboratory of Virology Wuhan Institute of VirologyChinese Academy of SciencesWuhan 430071China University of Chinese Academy of Sciences Beijing 100049China School of Life Sciences Division of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefei 230027China

The increasing emergence and re-emergence of RNA virus outbreaks underlines the urgent need to develop effective *** interference(RNAi)is a sequence-specific gene silencing mechanism that is triggered by small interfering RNAs(siRNAs)or short hairpin RNAs(shRNAs),which exhibits significant promise for antiviral ***2-dependent shRNA(agshRNA)generates a single-stranded guide RNA and presents significant advantages over traditional siRNA and *** this study,we applied a logistic regression algorithm to a previously published chemically siRNA efficacy dataset and built a machine learning-based model with high predictive *** this model,we designed siRNA sequences targeting diverse RNA viruses,including human enterovirus A71(EV71),Zika virus(ZIKV),dengue virus 2(DENV2),mouse hepatitis virus(MHV)and severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),and transformed them into *** validated the performance of our agshRNA design by evaluating antiviral efficacies of agshRNAs in cells infected with different *** the agshRNA targeting EV71 as an example,we showed that the anti-EV71 effect of agshRNA was more potent compared with the corresponding siRNA and ***,the antiviral effect of agshRNA is dependent on AGO2-processed guide RNA,which can load into the RNA-induced silencing complex(RISC).we also confirmed the antiviral effect of agshRNA in ***,this work develops a novel antiviral strategy that combines machine learning-based algorithm with agshRNA design to custom design antiviral agshRNAs with high efficiency.

关键词： AgshRNA Antiviral strategy Machine learning model

Structural insights into AtABCG25,an angiosperm-specific abscisic acid exporter

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Plant Communications 2024年第1期5卷 284-295页

作者： Jian Xin Yeling Zhou Yichun qiu He Geng Yuzhu wang Yi Song Jiansheng Liang Kaige Yan Department of Chemical Biology School of Life SciencesSouthern University of Science and TechnologyShenzhen 518055China Institute of Plant and Food Science Department of BiologySchool of Life SciencesSouthern University of Science and TechnologyShenzhen 518055China Max Planck Institute of Molecular Plant Physiology Potsdam-GolmGermany Institute for Biological Electron Microscopy Southern University of Science and TechnologyShenzhenGuangdongChina

Cellular hormone homeostasis is essential for precise spatial and temporal signaling responses and *** acid(ABA)plays pivotal roles in orchestrating various developmental and stress re-sponses and confersfitness benefits over ecological and evolutionary timescales in terrestrial *** ABA level is regulated by complex processes,including biosynthesis,catabolism,and ***25 is thefirst ABA exporter identified through genetic screening and affects diverse ABA *** the structural basis of ABA export by ABCG25 is critical for further manipulations of ABA homeostasis and *** used cryo-electron microscopy to elucidate the structural dynamics of AtABCG25 and successfully characterized different states,including apo AtABCG25,ABA-bound AtABCG25,and ATP-bound AtABCG25(E232q).Notably,AtABCG25 forms a homodimer that fea-tures a deep,slit-like cavity in the transmembrane domain,and we precisely characterized the critical residues in the cavity where ABA *** binding triggers closure of the nucleotide-binding domains and conformational transitions in the transmembrane *** show that AtABCG25 belongs to a conserved ABCG subfamily that originated during the evolution of *** subfamily neofunctionalized to regulate seed germination via the endosperm,in concert with the evolution of this angio-sperm-specific,embryo-nourishing ***,thesefindings provide valuable insights into the intricate substrate recognition and transport mechanisms of the ABA exporter AtABCG25,paving the way for genetic manipulation of ABA homeostasis and plantfitness.

关键词： AtABCG25 abscisic acid ABC transporters cryo-EM structure

High-capacity dilithium hydroquinone cathode material for lithium-ion batteries

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National Science Review 2024年第6期11卷 206-213页

作者： Yong Lu Haoqin Han Zhuo Yang Youxuan Ni Zhicheng Meng qiu Zhang Hao wu weiwei Xie Zhenhua Yan Jun Chen Frontiers Science Center for New Organic Matter Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) State Key Laboratory of Advanced Chemical Power SourcesCollege of ChemistryNankai University

Lithiated organic cathode materials show great promise for practical applications in lithium-ion batteries owing to their Li-reservoir characteristics. However, the reported lithiated organic cathode materials still suffer from strict synthesis conditions and low capacity. Here we report a thermal intermolecular rearrangement method without organic solvents to prepare dilithium hydroquinone（Li2q）, which delivers a high capacity of 323 m Ah g-1with an average discharge voltage of 2.8 V. The reversible conversion between orthorhombic Li2q and monoclinic benzoquinone during charge/discharge processes is revealed by in situ X-ray diffraction. Theoretical calculations show that the unique Li–O channels in Li2q are beneficial for Li+ion diffusion. In situ ultraviolet-visible spectra demonstrate that the dissolution issue of Li2q electrodes during charge/discharge processes can be handled by separator modification, resulting in enhanced cycling stability. This work sheds light on the synthesis and battery application of high-capacity lithiated organic cathode materials.

关键词： lithium-ion batteries cathode materials lithiated organic materials dilithium hydroquinone separator modification