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Microstructure and Mechanical Behavior of Mg-Based Bimetal Plates with High Formability Sleeve by Co-extrusion

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Acta Metallurgica Sinica(English Letters) 2024年第3期37卷 499-512页

作者： Yue-Hui Dang sheng-lin Liu Xiao-Lei Ai Xiao-Wei Feng Bo Feng Zhuo Tian Ying-Fei lin Huan-Tao Chen Kai-Hong Zheng School of Materials Science and Engineering Chang’an UniversityShaanxi 710064China Guangdong Key Laboratory of Metal Toughening Technology and Application Institute of New MaterialsGuangdong Academy of SciencesGuangzhou 510650China

In this study,microstructure and mechanical behavior of two types of Mg-based bimetal plates with a high formability sleeve were systematically studied,with a great emphasis on the effect of the interface characteristic and the sleeve fraction on the plasticity of composite plates.The rule of mixtures(ROM)for elongation was also addressed.The results show that when there is no or thin diffusion layer with thickness of about 3μm,Mg-based bimetal plates have a good plasticity with elongation of about 19-24%,and the ROM predicted elongations are very close to the experimental ones.In contrast,with a diffusion layer about 95-155μm thick,Mg-based bimetal plates exhibit a poor plasticity with elongation of about 11-17%,and the experimental elongations largely deviate from the ROM predictions.The plasticity of Mg-based bimetal plates increases with increasing sleeve fraction.This study provides new insights on the plastic deformation of Mg-based bimetal composites with a high formability sleeve.

关键词： Mg-based composites Co-extrusion Microstructure Mechanical behavior Plastic deformation

In situ tracking of the lithiation and sodiation process of disodium terephthalate as anodes for rechargeable batteries by Raman spectroscopy

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Nano Research 2024年第1期17卷 245-252页

作者： Xiu-Mei lin Chong Han Xin-Tao Yang Jia-sheng lin Wei-Qiang Yang Hong-Xu Guo Yao-Hui Wang Jin-Chao Dong Jian-Feng Li Department of Chemistry and Environment Science Fujian Province University Key Laboratory of Analytical ScienceMinnan Normal UniversityZhangzhou 363000China College of Energy College of Chemistry and Chemical EngineeringCollege of MaterialsState Key Laboratory of Physical Chemistry of Solid SurfacesiChEMXiamen UniversityXiamen 361005China Institute of Optical and Electronic Technology China Jiliang UniversityHangzhou 310018China

Organic compounds represent an appealing group of electrode materials for rechargeable batteries due to their merits of biomass,sustainability,environmental friendliness,and processability.Disodium terephthalate(Na_(2)C_(8)H_(4)O_(4),Na_(2)TP),an organic salt with a theoretical capacity of 255 mAh·g^(-1),is electroactive towards both lithium and sodium.However,its electrochemical energy storage(EES)process has not been directly observed via in situ characterization techniques and the underlying mechanisms are still under debate.Herein,in situ Raman spectroscopy was employed to track the de/lithiation and de/sodiation processes of Na2TP.The appearance and then disappearance of the–COOLi Raman band at 1625 cm^(-1) during the de/lithiation,and the increase and then decrease of the–COONa Raman band at 1615 cm^(-1) during the de/sodiation processes of Na2TP elucidate the one-step with the 2Li+or 2Na+transfer mechanism.We also found that the inferior cycling stability of Na2TP as an anode for sodium-ion batteries(SIBs)than lithium-ion batteries(LIBs)could be due to the larger ion radium of Na+than Li+,which results in larger steric resistance and polarization during EES.The Na2TP,therefore,shows greater changes in spectra during de/sodiation than de/lithiation.We expect that our findings could provide a reference for the rational design of organic compounds for EES.

关键词： disodium terephthalate(Na_(2)C_(8)H_(4)O_(4) Na2TP) in situ Raman spectroscopy de/lithiation de/sodiation mechanisms

Improved Identification Method and Fault Current Limiting Strategy for Commutation Failure in LCC-HVDC

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Journal of Modern Power Systems and Clean Energy 2022年第6期10卷 1761-1772页

作者： Jian Liu sheng lin Wenliang Zhong Lei Liu School of Electrical Engineering Southwest Jiaotong UniversityChengdu 610031China State Grid Sichuan Electric Power Research Institute Chengdu 610072China

line-commutated converter based high-voltage direct-current(LCC-HVDC)transmission systems are prone to subsequent commutation failure(SCF),which consequently leads to the forced blocking of HVDC links,affecting the operation of the power system.An accurate commutation failure(CF)identification is fairly vital to the prevention of SCF.However,the existing CF identification methods cause CF misjudge or detection lag,which can limit the effect of SCF mitigation strategy.In addition,earlier approaches to suppress SCF do not clarify the key factor that determines the evolution of extinction angle during system recovery and neglect the influence.Hence,this paper firstly analyzes the normal commutation process and CF feature based on the evolution topology of converter valve conduction in detail.Secondly,the energy in the leakage inductance of converter transformer is presented to characterize the commutation state of the valves.Then a CF identification method is proposed utilizing the leakage inductance energy.Thirdly,taking the key variable which is crucial to the tendency of extinction angle during the recovery process into account,a fault current limiting strategy for SCF mitigation is put forward.Compared with the original methods,the proposed methods have a better performance in CF identification and mitigation in terms of detection accuracy and mitigation effect.Finally,case study on PSCAD/EMTDC validates the proposed methods.

关键词： line commutated converter based high-voltage direct current(LCC-HVDC)transmission commutation failure identification commutation failure mitigation HVDC transmission control

A perceptual and predictive batch-processing memory scheduling strategy for a CPU-GPU heterogeneous system

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Frontiers of Information Technology & Electronic Engineering 2023年第7期24卷 994-1006页

作者： Juan FANG sheng lin Huijing YANG Yixiang XU Xing SU SU Faculty of Information Technology Beijing University of TechnologyBeijing 100124China

When multiple central processing unit(CPU)cores and integrated graphics processing units(GPUs)share off-chip main memory,CPU and GPU applications compete for the critical memory resource.This causes serious resource competition and has a negative impact on the overall performance of the system.We describe the competition for shared-memory resources in a CPU-GPU heterogeneous multi-core architecture,and a sharedmemory request scheduling strategy based on perceptual and predictive batch-processing is proposed.By sensing the CPU and GPU memory request conditions in the request buffer,the proposed scheduling strategy estimates the GPU latency tolerance and reduces mutual interference between CPU and GPU by processing CPU or GPU memory requests in batches.According to the simulation results,the scheduling strategy improves CPU performance by8.53%and reduces mutual interference by 10.38%with low hardware complexity.

关键词： CPU-GPU heterogeneous Multi-core Unified memory Access scheduling

Targetable elements in SARS-CoV-2 S2 subunit for the design of pan-coronavirus fusion inhibitors and vaccines

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Signal Transduction and Targeted Therapy 2023年第6期8卷 2577-2598页

作者： Liyan Guo sheng lin Zimin Chen Yu Cao Bin He Guangwen Lu Department of Emergency Medicine State Key Laboratory of BiotherapyWest China HospitalSichuan UniversityChengduSichuan610041China Disaster Medicine Center West China HospitalSichuan UniversityChengduSichuan610041China

The ongoing global pandemic of coronavirus disease 2019(COVID-19),caused by severe acute respiratory syndrome coronavirus 2(SARS‐CoV‐2),has caused devastating impacts on the public health and the global economy.Rapid viral antigenic evolution has led to the continual generation of new variants.Of special note is the recently expanding Omicron subvariants that are capable of immune evasion from most of the existing neutralizing antibodies(nAbs).This has posed new challenges for the prevention and treatment of COVID-19.Therefore,exploring broad-spectrum antiviral agents to combat the emerging variants is imperative.In sharp contrast to the massive accumulation of mutations within the SARS-CoV-2 receptor-binding domain(RBD),the S2 fusion subunit has remained highly conserved among variants.Hence,S2-based therapeutics may provide effective cross-protection against new SARS-CoV-2 variants.Here,we summarize the most recently developed broad-spectrum fusion inhibitors(e.g.,nAbs,peptides,proteins,and small-molecule compounds)and candidate vaccines targeting the conserved elements in SARS-CoV-2 S2 subunit.The main focus includes all the targetable S2 elements,namely,the fusion peptide,stem helix,and heptad repeats 1 and 2(HR1-HR2)bundle.Moreover,we provide a detailed summary of the characteristics and action-mechanisms for each class of cross-reactive fusion inhibitors,which should guide and promote future design of S2-based inhibitors and vaccines against new coronaviruses.

关键词： vaccines prevention elements

Evaluation of Voltage Quality and Energy Saving Benefits of Urban Rail Transit Power Supply Systems Considering the Access of Photovoltaics

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CSEE Journal of Power and Energy Systems 2023年第6期9卷 2309-2320页

作者： Ding Feng Hengkai Zhu Feng Wang Xiaojun Sun sheng lin Zhengyou He the School of Electrical Engineering Southwest Jiaotong UniversityChengdu 611756China. China Railway Design Group Co. Ltd.Tianjin 300000China

Along the route of urban rail transit(URT),the subway depots,parking lots,and elevated subway stations are equipped with sufficient photovoltaic(PV)generation conditions.The access of PVs in the URT power supply system should not only make full use of nearby renewable energy,but also improve the economic operation of the system.In order to quantify the impact of PV access on the URT power supply system,this paper proposes a method to evaluate the voltage quality and energy saving benefits of the URT power supply system,considering PV access.First,by fully considering the random fluctuations of PV output power,as well as the intermittency and impact of traction load,the URT power supply system with PV access is modeled.Then,such values as system voltage and power are calculated through the hybrid AC/DC load flow calculation method.Combined with the results of the load flow calculation,the indicators describing voltage quality and power saving benefits of the system are proposed to quantify the influence of PV access on the system.Finally,a case study concerning a certain section of a subway line is presented to verify the proposed method.It shows that the proposed method can effectively quantify the voltage quality and power saving benefits of the system after PV access,providing valuable insights for design and maintenance personnel to comprehend system state and operating characteristics.

关键词： Energy saving benefits photovoltaics urban rail transit voltage quality

The traditional Chinese medicines treat chronic heart failure and their main bioactive constituents and mechanisms

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Acta Pharmaceutica Sinica B 2023年第5期13卷 1919-1955页

作者： Jie Chen Xiaohong Wei Qian Zhang Yuzhuo Wu Guiyang Xia Huan Xia lingyan Wang Hongcai Shang sheng lin Key Laboratory of Chinese Internal Medicine of Ministry of Education and Beijing Dongzhimen HospitalBeijing University of Chinese MedicineBeijing 100700China

Chronic heart failure(CHF)is a severe public health problem with increasing morbidity and mortality,any treatment targeting a single session is insufficient to tackle this.CHF is characterized by reduced cardiac output resulting from neurohumoral dysregulation and cardiac remodeling,which might be related to oxidative stress,inflammation,endoplasmic reticulum stress,apoptosis,autophagy,mitochondrial function,and angiogenesis.These molecular mechanisms interact with each other through crosstalk.Historically,Chinese medicinal herbs have been widely applied in the treatment of CHF,and therapeutic effects of Chinese medicinal herbs and their ingredients have been scientifically confirmed over the past decades.Traditional Chinese medicine(TCM)with multiple components can confront the different pathogenesis of CHF through multiple targets.This review analyzes commonly used TCM patent drugs and TCM decoctions that are applicable to different stages of CHF based on clinical trials.Diverse bioactive ingredients in Chinese medicinal herbs have been found to treat CHF via multiple molecular mechanisms.This review comprehensively covers the key works on the effects and underlying mechanisms of TCM,herbal ingredients and synergistic effects of constituent compatibility in treating CHF,providing additional ideas to address this threat.

关键词： Natural ingredients Chronic heart failure Cardiac remodeling Chinese medicinal herbs Traditional Chinese medicine formula Multiple targets Constituent compatibility Synergistic effects

Circularly polarized luminescence of talarolactones(+)/(-)-A and(+)/(-)-C:The application of CPL-calculation in stereochemical assignment

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Chinese Chemical Letters 2022年第9期33卷 4253-4256页

作者： Guiyang Xia lingyan Wang Huan Xia Yuzhuo Wu Yanan Wang Haiyu Hu sheng lin Key Laboratory of Chinese Internal Medicine of Ministry of Education and Beijing Dongzhimen HospitalBeijing University of Chinese MedicineBeijing 100700China State Key Laboratory of Bioactive Substance and Function of Natural Medicines Institute of Materia MedicaChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100050China Key Laboratory for Qinghai-Tibet Plateau Phytochemistry of Qinghai Province College of PharmaceuticalQinghai Nationalities UniversityXining 810007China

Two pairs of fluorescent natural products,talarolactones(+)/(−)-A and(+)/(−)-C[(+)/(−)-1 and(+)/(−)-2],were discovered and characterized as a new family of circularly polarized luminescence-active small organic molecules(CPL-SOMs)with high fluorescence efficiency and fascinating CPL properties.The CPL(|glum|)levels of enantiomerically pure(+)/(−)-1 and(+)/(−)-2 in solution falls into the usual range(10−5−10−3)considering their pure organic nature,but the sign of CPL were found to be closely related to the absolute configuration of C-8.The high agreement of the measured CPL spectra of(+)/(−)-1 and(+)/(−)-2 with the time-dependent density functional theory(TDDFT)calculated ones demonstrated the usefulness of CPL-calculation as a unique method for stereochemical assignment.This study may open up a new perspective for the stereochemical studies and the future development of CPL materials.

关键词： Circularly polarized luminescence Natural products Stereochemical assignment Talarolactones(+)/(−)-A Talarolactones(+)/(−)-C

混合级联特高压直流输电线路纵联差动保护适应性分析

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电网技术 2024年第5期48卷 2170-2178,I0105-I0107页

作者：牟大林林圣李小鹏西南交通大学电气工程学院四川省成都市611756 国网四川省电力公司电力科学研究院四川省成都市610041

为探究现有高压直流输电线路纵联差动保护对混合级联特高压直流输电系统的适应性,结合混合级联特高压直流输电系统的运行方式,理论分析和仿真分析3种特殊运行方式下直流系统不同位置故障的故障特性和保护适应性。理论分析发现纵联差动... 详细信息

为探究现有高压直流输电线路纵联差动保护对混合级联特高压直流输电系统的适应性,结合混合级联特高压直流输电系统的运行方式,理论分析和仿真分析3种特殊运行方式下直流系统不同位置故障的故障特性和保护适应性。理论分析发现纵联差动保护适应性较好。仿真分析发现直流线路分布电容和逆变侧模块化多电平型换流器(modular multilevelconverter,MMC)控制特性影响在直流线路故障时直流线路电流延时自减值长时间处于波动状态,导致纵联差动保护长时间处于闭锁状态,此时,系统长时间承受MMC超大故障电流冲击。直流线路区外故障时整流侧与逆变侧直流电流差值的绝对值数值较大且长时间处于波动变化状态,纵联差动保护存在误动的风险。

关键词：混合级联特高压直流输电系统纵联差动保护适应性分析运行方式保护误动