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Nano Research 2009年第12期2卷 923-930页

作者： Xiaoling Xiao Li Wang Dingsheng Wang xiangming he Qing Peng Yadong Li Department of Chemistry Tsinghua UniversityBeijing 100084China Institute of Nuclear and New Energy Technology Tsinghua UniversityBeijing 100084China State Key Laboratory of New Ceramics and Fine Processing Tsinghua UniversityBeijing 100084China

Orthorhombic LiMnO_(2)nanoparticles and LiMnO_(2)nanorods have been synthesized by hydrothermal ***_(2)nanoparticles were synthesized by simple one-step hydrothermal *** obtain rod-like LiMnO_(2),γ-MnOOH nanorods were first synthesized and then the H+ions were completely replaced by Li+resulting in LiMnO_(2)*** electrochemical performances were thoroughly investigated by galvanostatic *** the LiMnO_(2)nanoparticles have smaller size than LiMnO_(2)nanorods,the latter exhibited higher discharge capacity and better *** example,the discharge capacities of LiMnO_(2)nanorods reached 200 mA·h/g over many cycles and remained above 180 mA·h/g after 30 ***,the maximum capacity of LiMnO_(2)nanoparticles was only 170 mA·h/g and quickly decreased to 110 mA·h/g after 30 *** with one-dimensional electronic pathways favor the transport of electrons along the length direction and accommodate volume changes resulting from charge/discharge *** the morphology of LiMnO_(2)may play an important role in electrochemical performance.

关键词： LiMnO_(2)nanoparticles nanorods hydrothermal synthesis one-dimensional nanomaterial electrochemical performance

Surface modification of polyolefin separators for lithium ion batteries to reduce thermal shrinkage without thickness increase

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Journal of Energy Chemistry 2015年第2期24卷 138-144页

作者： Peng Zhao Juping Yang Yuming Shang Li Wang Mou Fang Jianlong Wang xiangming he Institute of Nuclear and New Energy Technology Tsinghua University Huadong Institute of Lithium Ion Battery State Key Laboratory of Automotive Safety and Energy Tsinghua University

Surface chemical modification of polyolefin separators for lithium ion batteries is attempted to reduce the thermal shrinkage, which is im- portant for the battery energy density. In this study, we grafted organic/inorganic hybrid crosslinked networks on the separators, simply by grafting polymerization and condensation reaction. The considerable silicon-oxygen crosslinked heat-resistance networks are responsible for the reduced thermal shrinkage. The strong chemical bonds between networks and separators promise enough mechanical support even at high temperature. The shrinkage at 150 ℃ for 30 min in the mechanical direction was 38.6% and 4.6% for the pristine and present graft-modified separators, respectively. Meanwhile, the grafting organic-inorganic hybrid crosslink networks mainly occupied part of void in the internal pores of the separators, so the thicknesses of the graft-modified separators were similar with the pristine one. The half cells prepared with the modified separators exhibited almost identical electrochemical properties to those with the commercial separators, thus proving that, in order to enhance the thermal stability of lithium ion battery, this kind of grafting-modified separators may be a better alternative to conventional silica nanoparticle layers-coated polyolefin separators.

关键词： thermal shrinkage organic/inorganic hybrid crosslinked network chemical grafting separator lithium ion battery

An Aerial–Wall Robotic Insect That Can Land, Climb, and Take Off from Vertical Surfaces

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Research 2024年第1期2023卷 149-163页

作者： Qian Li Haoze Li Huan Shen Yangguang Yu Haoran he Xincheng Feng Yi Sun Zhiyuan Mao Guangming Chen Zongjun Tian Lida Shen xiangming Zheng Aihong Ji College of Mechanical and Electrical Engineering Nanjing University of Aeronautics and AstronauticsNanjingChina College of Aerospace Engineering Nanjing University of Aeronautics and AstronauticsNanjingChina State Key Laboratory of Mechanics and Control for Aerospace Structures Nanjing University of Aeronautics and AstronauticsNanjingChina

Insects that can perform flapping-wing flight,climb on a wall,and switch smoothly between the 2 locomotion regimes provide us with excellent biomimetic ***,very few biomimetic robots can perform complex locomotion tasks that combine the 2 abilities of climbing and ***,we describe an aerial–wall amphibious robot that is self-contained for flying and climbing,and that can seamlessly move between the air and *** adopts a flapping/rotor hybrid power layout,which realizes not only efficient and controllable flight in the air but also attachment to,and climbing on,the vertical wall through a synergistic combination of the aerodynamic negative pressure adsorption of the rotor power and a climbing mechanism with bionic adhesion *** the basis of the attachment mechanism of insect foot pads,the prepared biomimetic adhesive materials of the robot can be applied to various types of wall surfaces to achieve stable *** longitudinal axis layout design of the rotor dynamics and control strategy realize a unique cross-domain movement during the flying–climbing transition,which has important implications in understanding the takeoff and landing of ***,it enables the robot to cross the air–wall boundary in 0.4 s(landing),and cross the wall–air boundary in 0.7 s(taking off).The aerial–wall amphibious robot expands the working space of traditional flying and climbing robots,which can pave the way for future robots that can perform autonomous visual monitoring,human search and rescue,and tracking tasks in complex air–wall environments.

关键词： robot smoothly Vertical

Optically levitated micro gyroscopes with an MHz rotational vaterite rotor

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Microsystems & Nanoengineering 2024年第3期10卷 219-227页

作者： Kai Zeng xiangming Xu Yulie Wu Xuezhong Wu Dingbang Xiao College of Intelligence Science and Technology National University of Defense TechnologyChangsha 410073China College of Information and Communication National University of Defense TechnologyWuhan 430000China Key Laboratory of Satellite Navigation Technology National University of Defense TechnologyChangsha 410073China

The field of levitated optomechanics has experienced significant advancements in manipulating the translational and rotational dynamics of optically levitated particles and exploring their sensing *** concept of using optically levitated particles as gyroscopes to measure angular motion has long been explored but has not yet been proven either theoretically or *** this study,we present the first rotor gyroscope based on optically levitated high-speed rotating *** gyroscope is composed of a micrometer-size ellipsoidal vaterite particle that is driven to rotate at MHz frequencies in a vacuum *** an external angular velocity is input,the optical axis deviates from its initial position,resulting in changes in the frequency and amplitude of the rotational *** analyzing these changes,the angular velocity of the input can be accurately detected,making it the smallest rotor gyroscope in the *** angular rate bias instability of the gyroscope is measured to be 0.08°/s and can be further improved to as low as 10^(−9)°/h theoretically by cooling the motion and increasing the angular moment of the levitated *** work opens a new application paradigm for levitated optomechanical systems and may pave the way for the development of quantum rotor gyroscopes.

关键词： particles. rotational angular

Internal short circuit evaluation and corresponding failure mode analysis for lithium-ion batteries

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Journal of Energy Chemistry 2021年第10期30卷 269-280,I0008页

作者： Lishuo Liu Xuning Feng Christiane Rahe Weihan Li Languang Lu xiangming he Dirk Uwe Sauer Minggao Ouyang State Key Laboratory of Automotive Safety and Energy Tsinghua UniversityBeijing 100084China Chair for Electrochemical Energy Conversion and Storage Systems Institute for Power Electronics and Electrical Drives(ISEA)RWTH Aachen UniversityJaegerstrasse 17/19Aachen 52066Germany Institute of Nuclear and New Energy Technology Tsinghua UniversityBeijing 100084China

Internal short circuit(ISC)is the major failure problem for the safe application of lithium-ion batteries,especially for the batteries with high energy ***,how to quantify the hazard aroused by the ISC,and what kinds of ISC will lead to thermal runaway are still *** paper investigates the thermal-electrical coupled behaviors of ISC,using batteries with Li(Ni_(1/3)CO_(1/3)Mn_(1/3))O_(2) cathode and composite *** electrochemical impedance spectroscopy of customized battery that has no LiPF6 salt is utilized to standardize the resistance of ***,this paper compares the thermal-electrical coupled behaviors of the above four types of ISC at different *** is an area expansion phenomenon for the aluminum-anode type of *** expansion effect of the failure area directly links to the melting and collapse of separator,and plays an important role in further evolution of thermal *** work provides guidance to the development of the ISC models,detection algorithms,and correlated countermeasures.

关键词： Energy storage Lithium-ion battery Battery safety Internal short circuit Thermal runaway

Micromorphological Features of Paleo-Stagnic-Anthrosols at Archaeological Site of Sanxingdui,China

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Journal of Mountain Science 2008年第4期5卷 358-366页

作者： he Yurong HUANG Chengmin XU xiangming WANG Yanqiang he Xiubin Institute of Mountain Hazards ＆ Environment Chinese Academy of Sciences Chengdu 610041 China Department of Environmental Science and Engineering Sichuan University Chengdu 610065 China

The archaeological site of the Sanxingdui may date back as far as 5,000 years *** typical profiles of Palaeo-Stagnic-Anthrosols near the ancient site were selected,which aimed to identify diagnostic horizons employing methodology of soil taxonomic classification and to reveal the micromorphological properties of the *** long-term anthropogenic mellowing,the discernible differentiation between anthrostagnic epipedon and its subhorizons as well as hydragric horizon and its subhorizons occurred in Paleo-Stagnic-Anthrosols at the archaeological site of the *** micromorphological properties diversified among each specific diagnostic subhorizon,e.g.,the developed microstructure in cultivated subhorizon within anthrostagnic epipedon,closely arranged particles and considerable micropores beneficial to both of water conservation and filtration in plow subhorizon within anthrostagnic epipedon,and automorphic optical-orientation clays and calcareous corrosion in hydragric *** findings above of micromorphological features related with diagnostic horizons are significant for soil taxonomic classification.

关键词：土壤微观生态学分类学微观特征

Unveiling the parasitic-reaction-driven surface reconstruction in Ni-rich cathode and the electrochemical role of Li_(2)CO_(3)

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Journal of Energy Chemistry 2023年第10期85卷 126-136,I0006页

作者： Jiyu Cai Zhenzhen Yang Xinwei Zhou Bingning Wang Ana Suzana Jianming Bai Chen Liao Yuzi Liu Yanbin Chen Shunlin Song Xuequan Zhang Li Wang xiangming he Xiangbo Meng Niloofar Karami Baasit Ali Shaik Sulaiman Natasha A.Chernova Shailesh Upreti Brad Prevel Feng Wang Zonghai Chen Chemical Sciences and Engineering Division Argonne National Laboratory9700 South Cass AvenueLemontIL 60439USA Center for Nanoscale Materials Argonne National Laboratory9700 South Cass AvenueLemontIL 60439USA Condensed Matter Physics and Materials Science Department Brookhaven National LaboratoryUptonNY 11973USA Energy and Photon Sciences Directorate Brookhaven National LaboratoryUptonNY 11973USA Beijing Easprint Material Technology Co.Ltd. Beijing 100160China Institute of Nuclear and New Energy Technology Tsinghua UniversityBeijing 100084China Department of Mechanical Engineering University of ArkansasFayettevilleAR 72701USA Charge CCCV(C4V) 45 Murray Hill RoadCenter of ExcellenceBinghamton UniversityVestalNY 13850USA Primet Precision Materials 950 Danby RoadIthacaNY 14850USA Applied Materials Division Argonne National Labo

Nickel-rich transition-metal oxides are widely regarded as promising cathode materials for high-energydensity lithium-ion batteries for emerging electric vehicles. However, achieving high energy density in Ni-rich cathodes is accompanied by substantial safety and cycle-life obstacles. The major issues of Ni-rich cathodes at high working potentials are originated from the unstable cathode-electrolyte interface, while the underlying mechanism of parasitic reactions towards surface reconstructions of cathode materials is not well understood. In this work, we controlled the Li_(2)CO_(3) impurity content on LiNi_(0.83)Mn_(0.1)Co_(0.07)O_(2) cathodes using air, tank-air, and O_(2) synthesis environments. Home-built high-precision leakage current and on-line electrochemical mass spectroscopy experiments verify that Li_(2)CO_(3) impurity is a significant promoter of parasitic reactions on Ni-rich cathodes. The rate of parasitic reactions is strongly correlated to Li_(2)CO_(3) content and severe performance deterioration of Ni83 *** post-mortem characterizations via high-resolution transition electron microscope and X-ray photoelectron spectroscopy depth profiles reveal that parasitic reactions promote more Ni reduction and O deficiency and even rock-salt phase transformation at the surface of cathode materials. Our observation suggests that surface reconstructions have a strong affiliation to parasitic reactions that create chemically acidic environment to etch away the lattice oxygen and offer the electrical charge to reduce the valence state of transition metal. Thus, this study advances our understanding on surface reconstructions of Nirich cathodes and prepares us for searching for rational strategies.

关键词： Ni-rich cathodes Surface reconstructions Phase transformation Parasitic reactions Li_(2)CO_(3)

Acupuncture improves the live birth of patients with repeated implantation failure: a retrospective cohort study

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Journal of Traditional Chinese Medicine 2024年第4期44卷 830-838页

作者： SUN Junjian XIE henghui LI Huanhuan TIAN xiangming FANG Yigong ZHOU Wenhui Medical Center for Human Reproduction Beijing Chao-Yang HospitalCapital Medical University Department of Gynecology Beijing First Hospital of Integrated Chinese and Western Medicine Department of Acupuncture and Moxibustion Beijing Chao-Yang HospitalCapital Medical University Institute of Acupuncture and Moxibustion China Academy of Chinese Medical Sciences

OBJECTIVE: To explore the therapeutic efficacy of acupuncture treatment on repeated implantation failure(RIF) patients with cryo-thawed embryo transfer(CET).METHODS: In a retrospective cohort study, all eligible women undergoing RIF were recruited in our center from January 1, 2018 to December 31, 2021. The patients were grouped by whether an acceptance of acupuncture treatment before CET, including the acupuncture group(Acu-group, 55 cycles) and control group(Con-group,244 cycles). Data were analyzed by using binary logistic regression to explore the relationship of acupuncture treatment with pregnancy ***: The Acu-group had higher live-birth rate(LBR)[54.5% vs 41.0%, respectively; odds ratio(OR) = 1.105,95% confidence interval(CI)(1.029, 1.187), P = 0.006]and ongoing pregnancy rate(OPR) [56.4% vs 43.0%,respectively; OR = 1.100, 95% CI(1.025, 1.181), P =0.008] than the Con-group. There were no significant between-group differences in the rates of implantation [OR = 1.070, 95% CI(0.996, 1.149), P = 0.064], clinical pregnancy [OR = 1.065, 95% CI(0.997, 1.138), P =0.061], biochemical pregnancy [OR = 1.002, 95% CI(0.903, 1.112), P = 0.967], or miscarriage [OR = 0.778,95% CI(0.551, 1.099), P = 0.155]. Perinatal outcomes did not differ significantly between the two ***: Acupuncture treatment could improve the LBR and OPR in RIF patients with CET cycles,suggesting a potential adjuvant therapy of acupuncture to improve the pregnancy outcomes in RIF patients.

关键词： acupuncture cryo-thawed embryo transfer live birth rate repeated implantation failure

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In situ formation of ionically conductive nanointerphase on Si particles for stable battery anode

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Science China Chemistry 2021年第8期64卷 1417-1425页

作者： Xiaoxue Chen Gaofeng Ge Wenyu Wang Bao Zhang Jianjun Jiang Xuelin Yang Yuzhang Li Li Wang xiangming he Yongming Sun Wuhan National Laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhan430074China School of Optical and Electronic Information Huazhong University of Science and TechnologyWuhan430074China College of Electrical Engineering&New Energy Hubei Provincial Collaborative Innovation Center for New Energy MicrogridChina Three Gorges UniversityYichang443002China College of Materials and Chemical Engineering University of CaliforniaLos Angeles90095USA Institute of Nuclear and New Energy Technology Tsinghua UniversityBeijing100084China

Silicon(Si)is a promising anode candidate for next-generation lithium-ion batteries(LIBs)due to its high theoretical *** Si photovoltaic waste possesses good purity and high *** it as the raw material for battery anodes can synchronously solve the problem of solid waste pollution and enable high energy density LIBs.A critical issue impeding the practical application of Si is the undesirable side reactions at the electrolyte-particle interface and the resulting increase in impedance during ***,a Si-P core shell structure with chemical bonding at the Si-P interface is fabricated through a simple mechanical alloying reaction between red P and solar Si photovoltaic *** P nanoshell with thickness within 15 nm converts to Li3P during the initial lithiation process and maintains its phase on *** as-formed Li3P nanolayer functions as a stable,ionically conductive protective layer that reduces the direct contact between Si and electrolytes,and thus suppresses undesired side *** Si-P nanocomposite exhibits stable electrochemical cycling with a high reversible capacity of 1,178 mAh g^(−1)after 500 cycles at 1,200 mA g^(−1),as well as excellent rate capability(912 mAh g^(−1)at 2 C).With 15 wt%addition to graphite,a graphite/Si-P hybrid electrode shows a high overall reversible specific capacity of 447 mAh g^(−1)and 88.3%capacity retention after 100 cycles at high areal capacity of 2.64 mAh cm^(−2) at 100 mA g^(−1),indicating its promise as a drop-in anode in practical LIBs.

关键词： silicon anode Li3P interface stability lithium-ion batteries

Performance of Sn-Cu Alloy Anode at Low Temperature

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Journal of Materials Science & Technology 2005年第5期21卷 770-772页

作者： Jianguo REN, Weihua PU,xiangming he Chunrong WAN and Changyin JIANGMaterials Chemistry Lab, INET, Tsinghua University, Beijing 102201, China Materials Chemistry Lab. INET Tsinghua University Beijing 102201 China

Sn-Cu alloy anode was prepared by pulsed electrodeposition for lithium ion batteries, and its electrochemical performance was tested at low temperature. When temperature decreased from 25℃ to -20℃, the Sn-Cu alloy anode provided the capacity retentions of 76% in the electrolyte of 1 mol/L LiBF4/EC＋EMC＋γBL and 51% in the electrolyte of 1 mol/L LiPF6/EC＋DMC＋DEC. Under the same conditions, the graphite anode presented the capacity retentions of only 41% and 18%, respectively. The Sn-Cu alloy anode showed better performance in the electrolyte of 1 mol/L LiBF4/EC＋EMC＋γBL than in the electrolyte of 1 mol/L LiPF6/EC＋DMC＋DEC, and kept much higher capacity retention than that of graphite at -20℃. The Sn-Cu alloy anode in the electrolyte of 1mol/L LiBF4/EC＋EMC＋γBL （1：1：1, volume ratio） is promising for low temperature application of lithium batteries.

关键词： Sn-Cu alloy electrode Performance Low temperature Lithium batteries