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Science China(Technological Sciences) 2021年第12期64卷 2755-2761页

作者： XING WanDong MENG FanYan ning jinliang SUN JianWei YU Rong Department of Physics University of Science and Technology BeijingBeijing 100083China National Center for Electron Microscopy in Beijing School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China Department of Physics and Engineering Physics Tulane UniversityNew OrleansLA 70118USA

Accurate prediction of single-crystal elastic constants is critical for materials design and for understanding phase transition and elastic interactions in materials.In this work,the accuracy of elastic constants calculated with three density functional approximations has been compared,including the local density approximation(LDA),the generalized gradient approximation(GGA),and the recently developed strongly constrained and appropriately normed(SCAN)meta-GGA.The results show that SCAN and PBE describe elastic constants better than LDA.The strong correlation between the mechanical hardness and the stiffness of the softest eigenmode(SSE)has been given for above three density functionals.The correlation is capable of predicting accurately the hardness of covalent,ionic,and mixed covalent-ionic crystals,and providing us a convenient indicator for the discovery of hard or superhard materials.

关键词： hardness indicator elastic constants stiffness of softest eigenmode superhard materials

Sensitivity of the electronic and magnetic structures of cuprate superconductors to density functional approximations

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npj Computational Materials 2022年第1期8卷 266-276页

作者： Kanun Pokharel Christopher Lane James W.Furness Ruiqi Zhang jinliang ning Bernardo Barbiellini Robert SMarkiewicz Yubo Zhang Arun Bansil Jianwei Sun Department of Physics and Engineering Physics Tulane UniversityNew OrleansLA70118USA Theoretical Division Los Alamos National LaboratoryLos AlamosNM87545USA Center for Integrated Nanotechnologies Los Alamos National LaboratoryLos AlamosNM87545USA Department of Physics School of Engineering ScienceLUT UniversityFI-53851LappeenrantaFinland Physics Department Northeastern UniversityBostonMA02115USA

We discuss the crystal,electronic,and magnetic structures of La_(2−x)Sr_(x)CuO_(4)(LSCO)for x=0.0 and x=0.25 employing 13 density functional approximations,representing the local,semi-local,and hybrid exchange-correlation approximations within the Perdew–Schmidt hierarchy.The meta-generalized gradient approximation(meta-GGA)class of functionals is found to perform well in capturing the key properties of LSCO,a prototypical high-temperature cuprate superconductor.In contrast,the localspin-density approximation,GGA,and the hybrid density functional fail to capture the metal-insulator transition under doping.

关键词： functional electronic approximation

Subtle metastability of the layered magnetic topological insulator MnBi_(2)Te_(4) from weak interactions

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npj Computational Materials 2020年第1期6卷 362-367页

作者： jinliang ning Yanglin Zhu Jamin Kidd Yingdong Guan Yu Wang Zhiqiang Mao Jianwei Sun Department of Physics and Engineering Physics Tulane UniversityNew OrleansLA 70118USA Department of Physics The Pennsylvania State UniversityUniversity ParkPA 16802USA

Layered quantum materials can host interesting properties,including magnetic and topological,for which enormous computational predictions have been done.Their thermodynamic stability is much less visited computationally,which however determines the existence of materials and can be used to guide experimental synthesis.MnBi_(2)Te_(4) is one of such layered quantum materials that was predicted to be an intrinsic antiferromagnetic topological insulator,and later experimentally realized but in a thermodynamically metastable state.

关键词： synthesis state topological

High yield production of ultrathin fibroid semiconducting nanowire of Ta2Pd3Se8

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Nano Research 2020年第6期13卷 1627-1635页

作者： Xue Liu Sheng Liu Liubov Yu.Antipina Yibo Zhu jinliang ning Jinyu Liu Chunlei Yue Abin Joshy Yu Zhu Jianwei Sun Ana M.Sanchez Pavel B.Sorokin Zhiqiang Mao Qihua Xiong Jiang Wei Department of Physics and Engineering Physics Tulane UniversityNew OrleansLouisiana70118USA Division of Physics and Applied Physics Nanyang Technological UniversitySingapore637371Singapore National University of Science and Technology“MISiS” Moscow119049Russia Department of Polymer Science The University of AkronAkronOhio44325USA Technological Institute for Superhard and Novel Carbon Materials Moscow108840Russia Moscow Institute of Physics and Technology Dolgoprudny141700Russia Department of Mechanical Engineering Columbia UniversityNew YorkNew York10027USA Department of Physics University of WarwickCoventryCV47ALUK

Immediately after the demonstration of the high-quality electronic properties in various two dimensional(2D)van der Waals(vdW)crystals fabricated with mechanical exfoliation,many methods have been reported to explore and control large scale fabrications.Comparing with recent advancements in fabricating 2D atomic layered crystals,large scale production of one dimensional(1D)nanowires with thickness approaching molecular or atomic level still remains stagnant.Here,we demonstrate the high yield production of a 1D vdW material,semiconducting Ta2Pd3Se8 nanowires,by means of liquid-phase exfoliation.The thinnest nanowire we have readily achieved is around 1 nm,corresponding to a bundle of one or two molecular ribbons.Transmission electron microscopy(TEM)and transport measurements reveal the as-fabricated Ta2Pd3Se8 nanowires exhibit unexpected high crystallinity and chemical stability.Our low-frequency Raman spectroscopy reveals clear evidence of the existing of weak inter-ribbon bindings.The fabricated nanowire transistors exhibit high switching performance and promising applications for photodetectors.

关键词： van der Waals nanowire 1D semiconductor liquid exfoliation micro Raman spectroscopy electronic and optoelectronic device

Increased mitochondrial fission drives the reprogramming of fatty acid metabolism in hepatocellular carcinoma cells through suppression of Sirtuin 1

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Cancer Communications 2022年第1期42卷 37-55页

作者： Dan Wu Yi Yang Yiran Hou Zifeng Zhao ning Liang Peng Yuan Tao Yang jinliang Xing Jibin Li Department of Physiology and Pathophysiology State Key Laboratory of Cancer BiologyFourth Military Medical UniversityXi’anShaanxi 710032P.R.China Department of Pain Treatment Tangdu HospitalFourth Military Medical UniversityXi’anShaanxi 710032P.R.China Department of General Surgery Tangdu HospitalFourth Military Medical UniversityXi’anShaanxi 710038P.R.China Experimental Teaching Center of Basic Medicine Fourth Military Medical UniversityXi’anShaanxi 710038P.R.China

Background:Mitochondria are dynamic organelles that constantly change their morphology through fission and fusion processes.Recently,abnormally increased mitochondrial fission has been observed in several types of can-cer.However,the functional roles of increased mitochondrial fission in lipid metabolism reprogramming in cancer cells remain unclear.This study aimed to explore the role of increased mitochondrial fission in lipid metabolism in hepa-tocellular carcinoma(HCC)cells.Methods:Lipid metabolism was determined by evaluating the changes in the expressions of core lipid metabolic enzymes and intracellular lipid content.The rate of fatty acid oxidation was evaluated by[PH]-labelled oleic acid.The mito-chondrial morphology in HCC cells was evaluated by fluorescent staining.The expression of protein was determined by real-time PCR,imnmunohistochemistry and Western blotting.Results:Activation of mitochondrial fission significantly promoted de novo fatty acid synthesis in HCC cells through upregulating the expression of lipogenic genes fatty acid synthase(FASN),acetyl-CoA carboxylasel(ACCI),and elonga-tion of very long chain fatty acid protein 6(ELOVL6),while suppressed fatty acid oxidation by downregulating carnitine palmitoyl transferase 1A(CPTIA)and acyl-CoA oxidase 1(ACOX1).Consistently,suppressed mitochondrial fission exhibited the opposite effects.Moreover,in vitro and in vivo studies revealed that mitochondrial fission-induced lipid metabolism reprogramming significantly promoted the proliferation and metastasis of HCC cells.Mechanistically,mito-chondrial fission increased the acetylation level of sterol regulatory element-binding protein 1(SREBPI)and peroxisome proliferator-activated receptor coaC-tivator 1 alpha(PGC-1a)by suppressing nicotinamide adenine dinucleotide(NAD+)/Sirtuin 1(SIRTI)signaling.The elevated SREBP1 then upregulated the expression of FASN,ACC1 and ELOVL6 in HCC cells,while PGC-1c/PPARa sup-pressed the expression of CPTIA and ACOXL Conclusions:Increased mitochondrial fission plays a cruc

关键词： hepatocellular carcinoma lipogenesis fatty acid oxidation metabolic reprogramming mito-chondrial fission Sirtuin 1

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气枪阵列子波数值模拟

石油地球物理勘探 2003年第4期38卷 363-368页

作者：陈浩林宁书年熊金良王长春郭健中国矿业大学石油大学东方地球物理公司海上勘探事业部

气枪阵列作为震源具有很多优点,在海上地震勘探领域应用已久。国内对气枪的理论研究不多,认识不足。本文探讨了国际上主要的几种气枪单枪理论模型,同时对于气枪相干特性进行了较为深入的研究,提出了气枪阵列子波的算法。结合现场实际资... 详细信息

气枪阵列作为震源具有很多优点,在海上地震勘探领域应用已久。国内对气枪的理论研究不多,认识不足。本文探讨了国际上主要的几种气枪单枪理论模型,同时对于气枪相干特性进行了较为深入的研究,提出了气枪阵列子波的算法。结合现场实际资料,进行了对比和验证,得到了较为接近实际情况的结果。

关键词：气枪阵列震源自由气泡振荡子波海上地震勘探

基于改进型SMO的PMSM无传感器控制研究

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微电机 2024年第4期57卷 60-65,70页

作者：李宁江学焕张德志张金亮彭国生董万建湖北汽车工业学院电气与信息工程学院湖北十堰442002 上海致控驱动技术有限公司上海201806

针对传统滑模观测器(SMO)对永磁同步电机(PMSM)反电动势估计存在高频抖动而导致位置和转速误差较大的问题,分析设计了一种新型滑模观测器。首先,从滑模变结构控制原理出发,分析了传统SMO中控制函数的不足,其次,设计了新型控制函数,改善... 详细信息

针对传统滑模观测器(SMO)对永磁同步电机(PMSM)反电动势估计存在高频抖动而导致位置和转速误差较大的问题,分析设计了一种新型滑模观测器。首先,从滑模变结构控制原理出发,分析了传统SMO中控制函数的不足,其次,设计了新型控制函数,改善传统滑模观测器因使用开关函数造成估算值抖动过大的问题;同时使用频率自适应复系数滤波器代替传统的低通滤波器,提升估计转子位置和转速的精度。最后,在Matlab/Simulink平台搭建了算法仿真,仿真结果表明,该观测器能够很好地观测跟踪电机转速和其转子位置,能有效抑制高频抖振,提高滑模观测器估算精度,提高了PMSM无传感控制系统的稳定性。

关键词：滑模观测器永磁同步电机高频抖动无传感器控制复系数滤波器

Optical characterization of ZnO thin films deposited by RF magnetron sputtering method

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Science China(Technological Sciences) 2009年第8期52卷 2200-2203页

作者： TANG ning WANG jinliang XU HengXing PENG HongYong FAN Chao Department of Physics School of ScienceBeihang UniversityBeijing 100191China

This study investigated the process parameter effects on the structural and optical properties of ZnO thin film using radio frequency (RF) magnetron sputtering on amorphous glass substrates. The process parameters included RF power and working pressure. Results show that RF power was increased to promote the crystalline quality and decrease ZnO thin film defects. However, when the working pressure was increased to 3 Pa the ZnO thin film crystalline quality became worse. At a 200 W RF power and 1 Pa working pressure, the ZnO thin film with an optical band gap energy of 3.225 eV was obtained.

关键词： ZnO thin films RF magnetron sputtering XRD ultraviolet transmission spectrum

Efficient dehydration of carbohydrates to 5-hydroxymethylfurfural in ionic liquids catalyzed by tin(Ⅳ) phosphonate and zirconium phosphonate

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Science China Chemistry 2013年第11期56卷 1578-1585页

作者： ning Hui SONG jinliang HOU MinQiang YANG DeZhong FAN HongLei HAN BuXing Beijing National Laboratory for Molecular Sciences Institute of Chemistry Chinese Academy of Sciences

In this work,we synthesized tin(IV)phosphonate(SnBPMA)and zirconium phosphonate(ZrBPMA)by the reaction of SnCl4·5H2O or ZrOCl2·8H2O with N,N-bis(phosphonomethyl)aminoacetic acid,which was synthesized from a biomaterial glycine through a Mannich-type reaction.The SnBPMA and ZrBPMA were very efficient heterogeneous catalysts for the dehydration of fructose to produce 5-hydroxymethylfurfural(HMF),and the SnBPMA had higher activity than the ZrBPMA.The effects of solvents,temperature,reaction time,and reactant/solvent weight ratio on the reaction catalyzed by SnBPMA were investigated.It was demonstrated that the yield of HMF could reach 86.5%with 1-ethyl-3-methylimidazolium bromide([Emim]Br)as solvent,and the SnBPMA and SnBPMA/[Emim]Br catalytic system could be reused five times without considerable reduction in catalytic efficiency.Further study indicated that the SnBPMA and ZrBPMA in[Emim]Br were also effective for the dehydration of sucrose and inulin to produce HMF with satisfactory yields.

关键词：多相催化剂羟甲基糠醛锡(Ⅳ) 膦酸酯离子液体脱水反应时间糖类

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一起发电机漏氢事件的分析与处理

电力安全技术 2022年第12期24卷 58-60,65页

作者：宁效伟关锦良广东省能源集团广东粤电韶关发电厂有限公司广东韶关512100

介绍一起发电机漏氢事件的处理过程,分析了漏氢事件发生的原因并在此基础上深入剖析了发电机漏氢的危害,总结了漏氢的查找方法与处理措施,为类似的故障处理提供参考。

关键词：发电机漏氢排查方法判断与处理