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集成电路应用 2024年第1期41卷 260-261页

作者：孙立飞支昊国网沭阳县供电公司江苏223600

阐述变电系统的数字化技术特点,探讨变电站人工智能技术和大数据技术的应用,包括对变电站系统运营的巡视、变电站系统的运维操作、变电站系统运行的安全维护,分析大数据技术的应用成效。

关键词：人工智能大数据变配电系统

基于智能技术的变电运检现场安全管控系统设计与应用

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电子技术（上海） 2024年第1期53卷 236-237页

作者：支昊孙立飞国网沭阳县供电公司江苏223600

阐述变电站工程的安全状况,提出以人工智能为基础的变电运检现场安全管控措施,包括利用感知层捕捉信息,利用平台层有效采集与传输现场数据,利用应用层及时记录与控制现场违规操作。

关键词：变电运检人工智能现场作业安全管控系统

Responses of soil microbial communities to freeze–thaw cycles in a Chinese temperate forest

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Ecological Processes 2021年第1期10卷 903-920页

作者： Changpeng Sang Zongwei Xia lifei sun Hao sun Ping Jiang Chao Wang Edith Bai CAS Key Laboratory of Forest Ecology and Management Institute of Applied EcologyChinese Academy of SciencesShenyang 110016China. University of Chinese Academy of Sciences Beijing 100049China. Shandong Provincial Key Laboratory of Water and Soil Conservation and Environmental Protection College of Resources and EnvironmentLinyi UniversityLinyi 276000China. Key Laboratory of Geographical Processes and Ecological Security in Changbai Mountains Ministry of EducationSchool of Geographical SciencesNortheast Normal UniversityChangchun 130024China. Key Laboratory of Vegetation Ecology Ministry of EducationChangchun 130024China.

Background:Freeze–thaw events are common in boreal and temperate forest ecosystems and are increasingly infuenced by climate *** microorganisms play an important role in maintaining ecosystem stability,but their responses to freeze–thaw cycles(FTCs)are poorly *** conducted a feld freeze–thaw experiment in a natural Korean pine and broadleaf mixed forest in the Changbai Mountain Nature Reserve,China,to determine the dynamic responses of soil microbial communities to ***:Bacteria were more sensitive than fungi to *** biomass,diversity and community composition were not signifcantly afected by freeze–thaw regardless of the *** initial freeze–thaw resulted in increased bacterial biomass,diversity,and copiotrophic taxa *** FTCs reduced the bacterial biomass and *** with the initial FTC,subsequent FTCs exerted an opposite efect on the direction of change in the composition and function of the bacterial *** water content,dissolved organic carbon,ammonium nitrogen,and total dissolved phosphorus were important factors determining bacterial community diversity and composition during ***,the functional potentials of the microbial community involved in C and N cycling were also afected by ***:Diferent stages of FTCs have diferent ecological efects on the soil environment and microbial *** FTCs changed the soil nutrients and water availability and then mainly infuenced bacterial community composition,diversity,and functional potentials,which may disturb C and N states in this temperate forest *** study also improves our understanding of microbial communities regulating their ecological functions in response to climate change.

关键词： Freeze–thaw cycle Microbial diversity Microbial community composition Soil resource availability Functional potential

Exogenous nitrogen input skews estimates of microbial nitrogen use efficiency by ecoenzymatic stoichiometry

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Ecological Processes 2023年第1期12卷 625-631页

作者： lifei sun Daryl L.Moorhead Yongxing Cui Wolfgang Wanek Shuailin Li Chao Wang CAS Key Laboratory of Forest Ecology and Management Institute of Applied EcologyChinese Academy of SciencesShenyang 110016China Department of Environmental Sciences University of ToledoToledo 43606USA Sino-French Institute for Earth System Science College of Urban and Environmental SciencesPeking UniversityBeijing 100871China Division of Terrestrial Ecosystem Research Center of Microbiology and Environmental Systems ScienceUniversity of ViennaDjerassiplatz 11030 ViennaAustria

Background Ecoenzymatic stoichiometry models(EEST)are often used to evaluate microbial nutrient use efficiency,but the validity of these models under exogenous nitrogen(N)input has never been ***,we investigated the effects of long-term N addition(as urea)on microbial N use efficiency(NUE),compared EEST and^(18)O-labeling methods for determining NUE,and evaluated EEST’s theoretical assumption that the ratios of standard ecoenzymatic activities balance resource availability with microbial *** We found that NUE estimated by EEST ranged from 0.94 to *** contrast,estimates of NUE by the^(18)O-labeling method ranged from 0.07 to *** large differences in NUE values estimated by the two methods may be because the sum ofβ-N-acetylglucosaminidase and leucine aminopeptidase activities in the EEST model was not limited to microbial N acquisition under exogenous N inputs,resulting in an overestimation of microbial NUE by *** addition,the acquisition of carbon by N-acquiring enzymes also likely interferes with the evaluation of NUE by *** Our results demonstrate that caution must be exercised when using EEST to evaluate NUE under exogenous N inputs that may skew standard enzyme assays.

关键词： Extracellular enzyme Resource allocation Nitrogen addition Microbial metabolism limitation Isotope labeling

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Metallic and ferromagnetic MoS2 nanobelts with vertically aligned edges

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Nano Research 2015年第9期8卷 2946-2953页

作者： Guanchen Xu Xinsheng Wang Yupeng sun Xiao Chen Jingying Zheng lifei sun Liying Jiao Jinghong Li Department of Chemistry Tsinghua University Beijing 100084 China Key Laboratory of Colloid and Interface Chemistry Shandong University Jinan 250100 China

Edge effects are predicted to significantly impact the properties of low dimensional materials with layered structures. The synthesis of low dimensional materials with copious edges is desired for exploring the effects of edges on the band structure and properties of these materials. Here we developed an approach for synthesizing MoS2 nanobelts terminated with vertically aligned edges by sulfurizing hydrothermally synthesized MoO3 nanobelts in the gas phase through a kinetically driven process; we then investigated the electrical and magnetic properties of these metastable materials. These edge-terminated MoS2 nanobelts were found to be metallic and ferromagnetic, and thus dramatically different from the semiconducting and nonmagnetic two-dimensional （2D） and three-dimensional （3D） 2H-MoS2 materials. The transitions in electrical and magnetic properties elucidate the fact that edges can tune the properties of low dimensional materials. The unique structure and properties of this one-dimensional （1D） MoS2 material will enable its applications in electronics, spintronics, and catalysis.

关键词： MoS2 two-dimensional (2D)atomic crystal,nanobelt,edge effect,metallic,ferromagnetic

Growth of single-walled carbon nanotubes from Ag15 cluster catalysts

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Science Bulletin 2016年第12期61卷 917-920页

作者： Dake Hu Xin He lifei sun Guanchen Xu Liying Jiao Liang Zhao The Key Laboratory of Organic Optoelectronics and Molecular Engineering Ministry of EducationDepartment of ChemistryTsinghua UniversityBeijing 100084China The Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology Ministry of EducationDepartment of ChemistryTsinghua UniversityBeijing 100084China

Chirality-specific growth of single-walled carbon nanotubes(SWNTs) remains a challenge for their practical applications in electronics. Here, we explored the surface growth of SWNTs by utilizing the atomic-precise silver cluster complex [Ag_(15){1,3,5–(C:C)_3–C_6H_3}_2(Py[8])_3–(CF_3SO_3)_3](CF_3SO_3)_6(Py[8] is abbreviation for octamethylazacalix[8]pyridine) as a catalyst precursor. The diameters of most acquired SWNTs distributed in the range of 1.2–1.4 nm, which is suitable for making high performance field-effect transistors. The high quality of the obtained SWNTs was evidenced by Raman spectroscopy and electrical measurements. Successful growth of high quality SWNTs in this study foresees that rational design of metal-organic complexes as growth catalysts can open up a new avenue for the controllable synthesis of SWNTs.

关键词： Single-walled carbon nanotube Chirality Metal-organic cluster Catalyst RamanTEM

Atmospheric Degradation and Performance Recovery of Two-Dimensional MoS2 Field Effect Transistor

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Chinese Journal of Chemistry 2023年第21期41卷 2832-2836页

作者： lifei sun Zhixing Lu Rui Xu Zhewei Li Guanchen Xu Fengen Chen Zhihai Cheng Liying Jiao Key Laboratory of Organic Optoelectronics and Molecular Engineering of the Ministry of Education Department of ChemistryTsinghua UniversityBeijing100084 China Beijing Key Laboratory of Optoelectronic Functional Materials&Micro-nano Devices Department of PhysicsRenmin University of ChinaBeijing100872 China Advanced Materials Institute Qilu University of Technology(Shandong Academy of Sciences)JinanShandong250000 China

Two-dimensional(2D)transition metal dichalcogenides(TMDCs)showed great potentials in 2D nanoelectronic devices due to their abundant and unique *** performance stability of the 2D TMDCs devices turns into one of the keys for their practical applications but has been rarely ***,we investigated stability of MoS_(2)devices in ambient condition and contributed the device performance degradation to the surface oxidation of the contact metals with low work function,which increased the contact barrier and hindered the electron *** developed a new approach to recover the performance of the aged devices through the selective doping of contacts with organolithium,which prolonged the lifetime of MoS_(2)*** work not only provides important insights into the stability of 2D TMDCs devices,but also opens up a new avenue for optimizing the performance of 2D MoS_(2)devices.

关键词： MoS_(2) Field effect transistor Atmospheric degradation Performance recovery Semiconductors Doping Oxidation

Laser emission from low-loss cladding waveguides in Pr:YLF by femtosecond laser helical inscription

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Chinese Optics Letters 2022年第12期20卷 43-49页

作者： Yingying Ren Zemeng Cui lifei sun Chao Wang Hongliang Liu Yangjian Cai Shandong Provincial Engineering and Technical Center of Light Manipulations and Shandong Provincial Key Laboratory of Optics and Photonic Device School of Physics and ElectronicsShandong Normal UniversityJinan 250358China Key Laboratory of Optical Information Science and Technology Ministry of EducationInstitute of Modern OpticsNankai UniversityTianjin 300071China School of Physical Science and Technology Soochow UniversitySuzhou 215006China

Depressed cladding waveguides are fabricated in Pr:LiYF_(4)(YLF)crystal by femtosecond laser inscription following a helical *** the optimized parameters,the propagation loss of the waveguide is around 0.12 dB/cm for multimode *** optical pumping with InGaN laser diodes at 444 nm,efficient waveguide lasers in the orange around604 nm(π-polarized)are achieved with minimum lasing threshold of 119.8 mW,maximum slope efficiency of 16.6%,and maximum output power of 120.6 *** from their optimized performances,the waveguides produced in this work are promising for applications as compact orange laser sources.

关键词： femtosecond laser helical inscription Pr:YLF crystal optical waveguide laser

Growth of large-area aligned pentagonal graphene domains on high-index copper surfaces

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Nano Research 2016年第7期9卷 2182-2189页

作者： Kailun Xia Vasilii I. Artyukhov lifei sun Jingying Zheng Liying Jiao Boris I. Yakobson Yingying Zhang Department of Chemistry Tsinghua University Beijing 100084 China Center for Nano and Micro Mechanics Tsinghua University Beijing 100084 China Department of Materials Science and Nano Engineering Rice University Houston TX 77005 USA

Single-crystal graphene domains grown by chemical vapor deposition （CVD） intrinsically tend to have a six-fold symmetry; however, several factors can influence the growth kinetics, which can in turn lead to the formation of graphene with different shapes. Here we report the growth of oriented large-area pentagonal single-crystal graphene domains on Cu foils by CVD. We found that high-index Cu planes contributed selectively to the formation of pentagonal graphene. Our results indicated that lattice steps present on the crystalline surface of the underlying Cu promoted graphene growth in the direction perpendicular to the steps and finally led to the disappearance of one of the edges forming a pentagon. In addition, hydrogen promoted the formation of pentagonal domains. This work provides new insights into the mechanism of graphene growth.

关键词： pentagonal graphene copper foil high index plane chemical vapor deposition large area

Near-infrared lasing and tunable upconversion from femtosecond laser inscribed Nd,Gd:CaF_(2)waveguides

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Chinese Optics Letters 2021年第8期19卷 6-11页

作者： Ruonan Li lifei sun Yangjian Cai Yingying Ren Hongliang Liu Mark D.Mackenzie Ajoy K.Kar Center of Light Manipulations and Applications&Shandong Provincial Key Laboratory of Optics and Photonic Device School of Physics and ElectronicsShandong Normal UniversityJinan 250014China Institute of Modern Optics Nankai UniversityTianjin 300350China Institute of Photonics and Quantum Sciences Heriot-Watt UniversityEdinburgh EH144ASUK

Optical channel waveguides with depressed cladding configurations have been produced in Nd,Gd∶CaF_(2)laser crystals by using ultrafast laser *** properties are investigated in terms of guiding behaviors and localized laserinduced lattice *** an optical pump of 808 nm light,continuous-wave waveguide lasing at 1.06μm is achieved,with a single-mode operation and a minimum lasing threshold of 98.8 m ***,the visible emissions of Nd^(3+)with short wavelengths ranging from 415 nm to 550 nm and long wavelengths from 550 nm to 625 nm are observed upon 808 nm laser excitation via the up-converted *** intensity ratios of two wavelength ranges are proved to be tunable through changing the pumping polarizations.

关键词： femtosecond laser inscription optical waveguide CaF_(2)crystal laser upconversion