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Scalar or Vector Tetraquark State Candidate: Z_c(4100)

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Communications in Theoretical Physics 2019年第11期71卷 1319-1327页

作者： zhi-gang Wang Department of Physics North China Electric Power University

In this article, we separate the vector and axialvector components of the tensor diquark operators explicitly,construct the axialvector-axialvector type and vector-vector type scalar tetraquark currents and scalar-tensor type tensor tetraquark current to study the scalar, vector and axialvector tetraquark states with the QCD sum rules in a consistent way. The present calculations do not favor assigning the Zc(4100) to be a scalar or vector tetraquark state. If the Zc(4100) is a scalar tetraquark state without mixing effects, it should have a mass about 3.9 GeV or 4.0 GeV rather than4.1 GeV;on the other hand, if the Zc(4100) is a vector tetraquark state, it should have a mass about 4.2 GeV rather than 4.1 GeV. However, if we introduce mixing, a mixing scalar tetraquark state can have a mass about 4.1 GeV. As a byproduct, we obtain an axialvector tetraquark candidate for the Zc(4020).

关键词： Tetraquark state QCD sum rules

Inhibition of viability of human retinal microvascular endothelial cells by vialinin A under high glucose condition

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International Journal of Ophthalmology(English edition) 2024年第10期17卷 1809-1815页

作者： zhi-gang Chen Gao-Qin Liu Wei-Ming Liu Pei-Rong lu Department of Ophthalmology the First Affiliated Hospital of Soochow UniversitySuzhou 215006Jiangsu ProvinceChina Jiangsu Clinical Immunology Institute the First Affiliated Hospital of Soochow UniversitySuzhou 215006Jiangsu ProvinceChina

AIM:To investigate the effects of vialinin A on viability of human retinal endothelial cells(HRECs)under high glucose condition and its potential ***:The HRECs were divided into four groups:normal glucose control group(NG,5 mmol/L D-glucose),high glucose group(HG,30 mmol/L D-glucose),HG+1μmol/L vialinin A group,and HG+5μmol/L vialinin A *** cell viabilities were measured with cell counting kit-8(CCK-8)assay for proliferation,with scratch assay for migration,and tube formation,for evaluation of the impact of vialinin A on cellular ***-time PCR and Western blotting were used to determine the expression level of vascular endothelial growth factor(VEGF).RESULTS:The proliferative capacity and migration of HRECs was reduced by 5μmol/L vialinin A in high glucose environment(both Plucose-induced tube formation of *** expression level of VEGF and PI3K in HRECs was also significantly decreased by vialinin A(PluSION:Vialinin A inhibits the cell viability of *** may serve as a potential target for anti-angiogenic therapy.

关键词： vialinin A vascular endothelial growth factor human retinal endothelial cells cell viability

基于无人机多光谱数据和氮素空间分异的玉米冠层氮浓度估算

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作物学报 2025年第1期51卷 189-206页

作者：郝琪陈天陆王富贵王振白岚方王永强王志刚内蒙古农业大学农学院内蒙古呼和浩特010010

作物冠层氮素营养的遥感诊断对指导作物精准施氮,提高作物氮效率和产量具有重要意义。本研究针对玉米冠层纵深大影响无人机估算氮浓度精度的问题,基于2022年和2023年不同氮肥运筹处理下田间无人机多光谱数据和氮浓度实测数据,分析玉米... 详细信息

作物冠层氮素营养的遥感诊断对指导作物精准施氮,提高作物氮效率和产量具有重要意义。本研究针对玉米冠层纵深大影响无人机估算氮浓度精度的问题,基于2022年和2023年不同氮肥运筹处理下田间无人机多光谱数据和氮浓度实测数据,分析玉米冠层氮浓度空间分布特征,并利用随机森林算法确定估算冠层氮浓度的有效叶层。进一步结合随机森林算法和多光谱植被指数构建有效叶层氮浓度估算模型,最终将有效叶层氮浓度转换到冠层尺度实现冠层氮浓度的估算。结果表明:(1)九叶展期和大喇叭口期玉米冠层氮浓度表现为上层叶片>中层叶片>下层叶片,吐丝期和乳熟期表现为中层叶片>上层叶片>下层叶片。(2)各时期估算冠层氮浓度的有效叶层分别为下层、中层、中层和中层。与支持向量回归模型相比,随机森林回归估算冠层氮浓度的精度较高。(3)结合随机森林算法,基于有效叶层氮浓度估算冠层氮浓度的平均RMSE、NRMSE和MAE分别为0.10%、4.41%和0.07%,而直接基于植被指数估算冠层氮浓度的平均RMSE、NRMSE和MAE分别为0.19%、9.00%和0.15%。综上,玉米冠层氮浓度存在空间分异特征,估算冠层氮浓度时考虑基于随机森林和植被指数估算的有效叶层氮浓度能明显提高冠层氮浓度的估算精度。本研究确定的考虑空间分异的冠层氮浓度估算框架可为玉米氮素营养实时诊断提供理论支撑。

关键词：玉米冠层氮浓度氮素空间分异多光谱数据机器学习

Electro-optical properties cholesteric liquid of polymer stabilized crystal film＊

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Chinese Physics B 2011年第2期20卷 295-301页

作者： Ma Ji Zheng zhi-gang Liu Yong-gang Xuan Li State Key Laboratory of Applied Optics Changchun Institute of Optics Fine Mechanics and Physics Chinese Academy of Sciences Changchun 130033 China Department of Physics School of Science East China University of Science and Technology Shanghai 200237 China

Liquid crystals （LCs） and polymers are extensively used in various electro-optical applications. In this paper, normal mode polymer stabilized cholesteric LC film is prepared and studied. The effects of chiral dopant and monomer concentrations on the electro-optical properties, such as contrast ratio, driving voltage, hysteresis width and response time, are investigated. The reasons of electro-optical properties influenced by the concentrations of the materials are discussed. Through the proper material recipe, the electro-optical properties of polymer stabilized cholesteric LC film can be optimized.

关键词： liquid crystal polymer electro-optical property cholesteric liquid crystal

Remarks on the recent progress of Materials Genome Initiative

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Science Bulletin 2015年第22期60卷 1966-1968页

作者： Xiao-gang lu School of Materials Science and Engineering Shanghai University Materials Genome Institute Shanghai University

The Materials Genome Initiative(MGI)has attracted great attention globally since June 2011,when the US President Obama announced Advanced Manufacturing Partnership(AMP),in which MGI is a key *** June 2014,the US National Science and Technology Council published‘‘Materials Genome Initiative Strategic Plan’’,describing in detail the strategy that guides and coordinates US Federal activities and provides a clear technical path

关键词：基因组计划材料科学技术委员会美国总统先进制造组成部分 AMP

Microstructure and mechanical property of Sn–Ag–Cu solder material

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Rare Metals 2017年第3期36卷 193-197页

作者： Yi-gang Kong zhi-gang Kong Feng-Min Shi School of Mechanical Engineering Taiyuan University of Science and TechnologyTaiyuan 030024China Research Laboratory of Electrical Contacts Beijing University of Posts and TelecommunicationsBeijing 100876China Technology Department Jinan No.10 Radio Factory Co.Ltd.Jinan 250100China

Among the lead-free solder materials,Sn-Ag-Cu alloys have many advantages,such as good wetting property,superior interfacial properties and high creep *** this article,the organization and welding performance of Sn-Ag-Cu material were *** surface morphology of the two alloys was observed by stereoscopic microscope and scanning electron microscope （SEM）.Chemical constitution was examined by X-ray energy-dispersive spectroscopy （EDS）.The mechanical properties of Sn-Ag-Cu solder were evaluated systematically compared with those of Sn-Cu *** results show that Sn-Ag-Cu solder based on different solder pads has different welding *** thickness of intermetallic compound （IMC） at the interface increases with aging *** the gold-plated pads,there are a large number of IMC graphic,and in the welding interface,it can reduce the reliability of electrical *** Sn-Ag-Cu solder joints show a superior mechanical property over the traditional Sn-Cu *** number of dimples decreases and that of cavities increases for Sn-Cu0.7 alloy and the fracture surfaces of Sn-Ag3.0-Cu0.5 alloy have many small size dimples which are homogeneously distributed.

关键词： Lead-free solder Organization Weldingperformance Intermetallic compound

Dynamics of rotator chain with dissipative boundary

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Frontiers of physics 2014年第4期9卷 511-518页

作者： Pu Ke zhi-gang Zheng Department of Physics and the Beijing Hong Kong Singapore Joint Center for Nonlinear and Complex Systems (Beijing) Beijing Normal University Beijing 100875 China

We study the deternfinistic dynanfics of rotator chain with purely mechanical driving on the boundary by stability analysis and numerical sinmlation. Globally synchronous rotation, clustered synchronous rotation, and split synchronous rotation states are identified. In particular, we find that the single-peaked wariance distribution of angular momenta is the consequence of the deterministic dynamics. As a result, the operational definition of temperature used in the previous studies on rotator chain should be revisited.

关键词： rotator chain energy conduction

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变电站便携式SF6气瓶加热装置研究

电子设计工程 2018年第5期26卷 98-101,106页

作者：董海波张嘉倍行明涛李志刚路成钢梁凯郑州华力信息技术有限公司河南郑州450006 东北大学辽宁沈阳110167

针对电力检修过程中,经常需要给SF6气体绝缘设备充补气。在充补气过程中遇到的气瓶降温速度快、瓶体表面结冰、工作效率低、气体残留率高等问题,本文设计一套具有独立温度监控器的便携式工业热风机对SF6气瓶表面加热的方案。独立温度监... 详细信息

针对电力检修过程中,经常需要给SF6气体绝缘设备充补气。在充补气过程中遇到的气瓶降温速度快、瓶体表面结冰、工作效率低、气体残留率高等问题,本文设计一套具有独立温度监控器的便携式工业热风机对SF6气瓶表面加热的方案。独立温度监控器采用ARM内核的STM32103R8作为主控芯片,并通过DS18B20做为温度检测单元实现实时温度采集。另外加热过程中为了持续保温,还专门给SF6气瓶增加了保温隔热瓶套。结合多次现场实际实验测试,装置运行安全可靠。通过实验测试数据对比计算,对SF6气体绝缘设备充补气效率提高了10%。瓶体内的气体残留率降低了8%。本装置已经在多个变电站多次使用。

关键词： SF6气体绝缘设备加热装置自动控制 DS18820

Distributed Adaptive Output Consensus of Unknown Heterogeneous Non-Minimum Phase Multi-Agent Systems

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IEEE/CAA Journal of Automatica Sinica 2023年第4期10卷 997-1008页

作者： Wenji Cao lu Liu gang Feng Department of Biomedical Engineering City University of Hong KongHong Kong SARChina

This article addresses the leader-following output consensus problem of heterogeneous linear multi-agent systems with unknown agent parameters under directed *** dynamics of followers are allowed to be non-minimum phase with unknown arbitrary individual relative *** is contrary to many existing works on distributed adaptive control schemes where agent dynamics are required to be minimum phase and often of the same relative degree.A distributed adaptive pole placement control scheme is developed,which consists of a distributed observer and an adaptive pole placement control *** is shown that under the proposed distributed adaptive control scheme,all signals in the closed-loop system are bounded and the outputs of all the followers track the output of the leader *** effectiveness of the proposed scheme is demonstrated by one practical example and one numerical example.

关键词： Adaptive pole placement control heterogeneous multi-agent systems leader-following output consensus non-minimum phase