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心肌梗死后心室电重构的细胞和分子生物学机制

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中国病理生理杂志 2008年第11期24卷 2276-2281页

作者：罗涛李玉明天津医科大学天津300070 中国人民武装警察部队医学院附属医院心血管病研究所天津300162

Arrhythmia is common in cardiovascular diseases, especially after myocardial infarction. This article reviews the electrophysiologic changes following myocardial infarction at different phases. Modulations of ion channel function that might contribute to electrical remodeling, such as cellular (autocrine/paracrine) factors and regulators of ion channel gene, are discussed. Unresolved problems in ventricular electrical remodeling after myocardial infarction are also considered.

关键词：心律失常心肌梗死心室电-重构

Probing the special angle in twisted bilayer MoS_(2)via angle-dependent scanning tunneling microscopy studies

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Science China(Physics,Mechanics & Astronomy) 2025年第2期68卷 153-160页

作者： Xueying liu Shiying liu yulong Xiao Chang Xu Jiaxin Wu Kaihui li Si-yu li Anlian Pan Key Laboratory for Micro-Nano Physics and Technology of Hunan Province Hunan Institute of Optoelectronic Integration and College of Materials Science and EngineeringHunan UniversityChangsha410082China School of Physics and Electronics Hunan Normal UniversityChangsha410081China

Twisted transition metal dichalcogenides(TMDs)homo-bilayers host unique quantum properties,which can be tuned by interlayer twist angleθ.However,the systematic evolution of their typical electronic properties with respect to the twist angleθ,which is crucial for identifying the“special angle”analogous to the“magic angle”of twisted bilayer graphene in correlation physics studies,remains incompletely ***,via scanning tunneling microscopy(STM)and spectroscopy(STS),we investigate the variation of the moirépotential,flat band,and layer polarization characteristics across a wide range of twist angleθin twisted bilayer MoS_(2)(TB-MoS_(2)).The moirépotential of the valence band exhibits a non-monotonic variation withθ,peaking at a maximum value up to 204 me Vatθ~1.7°.Concurrently,at the sameθ,the bandwidth of the flat band at theΓ_(V)point of the valence band attains its minimum,precisely signifying the“special angle”θ_(c)~1.7°in TB-MoS_(2).Interestingly,layer polarization in the moirésuperlattice is spatially visualized through the distribution of local density of states(LDOS)at the energies of bothΓ_(V)and K_(V)points of the valence band,where the polarization degree at theΓ_(V)point demonstrates a close dependency onθ.Our findings deepen understanding of twist-angle effect in TMDs,advancing both fundamental physics and practical application.

关键词： twisted bilayer MoS_(2) flat band moirépotential twist-angle dependence scanning tunneling microscopy

Numerical Study of Cavitating Flows around a Hydrofoil with Deep Analysis of Vorticity Effects

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Fluid Dynamics & Materials Processing 2025年第1期21卷 179-204页

作者： Shande li Wen’an Zhong Shaoxing yu Hao Wang Xichang Satellite Launch Center Wenchang571300China College of Water Resources and Civil Engineering China Agricultural UniversityBeijing100083China

This paper aims to numerically explore the characteristics of unsteady cavitating flow around a NACA0015 hydrofoil,with a focus on vorticity *** simulation utilizes a homogeneous mixture model coupled with a filter-based density correction turbulence model and a modified Zwart cavitation *** study investigates the dynamic cavitation features of the thermal fluid around the hydrofoil at various incoming flow *** systematically elucidates the evolution of cavitation and vortex dynamics corresponding to each velocity *** results indicate that with increasing incoming flow velocity,distinct cavitation processes take place in the flow field.

关键词： Cavitating flow hydrofoil flow velocity vorticity Computational Fluid Dynamics(CFD)

Residual symmetry and interactions between solitons and periodic waves of the Drinfeld-Sokolov-Satsuma-Hirota system

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Communications in Theoretical Physics 2025年第1期77卷 1-10页

作者： Jie-tong li Jun yu Xi-zhong liu Institute of Nonlinear Science Shaoxing UniversityShaoxing 312000China

In this paper,the Drinfeld-Sokolov-Satsuma-Hirota(DSSH)system is studied by using residual symmetry and the consistent Riccati expansion(CRE)method,*** residual symmetry of the DSSH system is localized to lie point symmetry in a properly prolonged system,based on which we get a new Bäcklund transformation for this *** symmetry reduction solutions of the DSSH system are obtained by applying the classical lie group approach on the prolonged ***,the DSSH system proves to be CRE integrable and new interesting interaction solutions between solitons and periodic waves are generated and analyzed.

关键词： Drinfeld-Sokolov-Satsuma-Hirota system residual symmetry consistent Riccati expansion

PAFC-PDM复合混凝剂强化混凝去除水库源水中的藻类

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中国环境科学 2014年第7期34卷 1763-1768页

作者：李明玉孙玉君刘丽娟潘倩汪琳任刚暨南大学环境工程系暨南大学水处理工程研究中心广东广州510630

将聚二甲基二烯丙基氯化铵（PDMDAAC）与聚合氯化铝铁（PAFC）复合制备了新型复合混凝剂PAFC-PDMDAAC （PAFC-PDM）,对含藻的水库原水进行强化混凝处理研究.研究对比了PAFC-PDM,PAFC与预氯化工艺的除藻效果,并对其混凝除藻机理进行了初... 详细信息

将聚二甲基二烯丙基氯化铵（PDMDAAC）与聚合氯化铝铁（PAFC）复合制备了新型复合混凝剂PAFC-PDMDAAC （PAFC-PDM）,对含藻的水库原水进行强化混凝处理研究.研究对比了PAFC-PDM,PAFC与预氯化工艺的除藻效果,并对其混凝除藻机理进行了初步探讨.结果表明,对于藻细胞数为7.98×10^6-1.17×10^7cells/L和浊度为2.56-3.59NTU的水库原水,当PAFC-PDM投加量为1.0mg/L时（以Al2O3计）,藻类和浊度的去除率分别达到93.5%和81.7%,显著优于PAFC的混凝处理效果；对藻细胞进行扫描电镜和预氯化副产物分析表明,预氯化杀藻除藻方法,不仅破坏了藻细胞结构,而且产生了三卤甲烷类氯化消毒副产物,影响饮水水质；采用PAFC-PDM强化混凝工艺除藻,不破坏藻细胞,无消毒副产物.

关键词：强化混凝除藻聚合氯化铝铁聚二甲基二烯丙基氯化铵

Palaeowind reconstruction from Lower Cretaceous wavedominated depositional records of the Tanan Depression,Northeast Asia

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Journal of Oceanology and limnology 2025年第1期43卷 41-56页

作者： Xinyu XUE Zaixing JIANG Chao liU li WANG Huanyu XIE lizhou SONG ming SU School of Marine Science Sun Yat-sen UniversityZhuhai 519083China School of Energy Resources China University of Geosciences(Beijing)Beijing 100083China Sinopec Matrix Corporation Qingdao 266000China Daqing Oilfield Production Technology Institute Daqing 163453China

Palaeowind regime is an important component for reconstructing palaeoclimate and understanding ancient global *** applied the beach-ridge thickness technique(BTT)and the longshore-bar thickness technique(LTT)to reconstruct the Early Cretaceous palaeowind velocities based on depositional records of Tanan Depression in Northeast *** thickness of beach ridges and nearshore bars is the most important parameter for applying the BTT and the LTT *** identified 22 beach ridges and 23 nearshore bars based on drilling cores and wireline-log data in the Tanan *** velocities calculated by using the LTT method ranged from 10.84 to 13.66 m/s,showing a narrower range than those calculated by using the BTT method(7.58–15.93 m/s).We further analyzed the underlying factors causing the difference between the results derived from these two methods based on the sedimentary process of the beach ridge and the nearshore *** reconstructed wind regime was assumed to be the summer monsoon originating from the Mongol-Okhotsk Ocean before it had been completely enclosed,which provides valuable insight into the understanding of the atmospheric circulation in Northeast Asia during the Early Cretaceous.

关键词： palaeowind beach ridge nearshore bar Early Cretaceous East Asia Summer Monsoon

An efficient and accurate numerical method for simulating close-range blast loads of cylindrical charges based on neural network

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Defence Technology(防务技术) 2025年第2期44卷 257-271页

作者： Ting liu Changhai Chen Han li Yaowen yu yuansheng Cheng School of Naval Architecture and Ocean Engineering Huazhong University of Science and TechnologyWuhan 430074China Hubei Key Laboratory of Naval Architecture and Ocean Engineering Hydrodynamics Wuhan 430074China Collaborative Innovation Center for Advanced Ship and Deep-Sea Exploration Shanghai 200240China

To address the problems of low accuracy by the CONWEP model and poor efficiency by the Coupled Eulerian-Lagrangian(CEL)method in predicting close-range air blast loads of cylindrical charges,a neural network-based simulation(NNS)method with higher accuracy and better efficiency was *** NNS method consisted of three main ***,the parameters of blast loads,including the peak pressures and impulses of cylindrical charges with different aspect ratios(L/D)at different stand-off distances and incident angles were obtained by two-dimensional numerical ***,incident shape factors of cylindrical charges with arbitrary aspect ratios were predicted by a neural ***,reflected shape factors were derived and implemented into the subroutine of the ABAQUS code to modify the CONWEP model,including modifications of impulse and *** reliability of the proposed NNS method was verified by related experimental *** accuracy improvement was acquired by the proposed NNS method compared with the unmodified CONWEP ***,huge efficiency superiority was obtained by the proposed NNS method compared with the CEL *** proposed NNS method showed good accuracy when the scaled distance was greater than 0.2 m/kg^(1/3).It should be noted that there is no need to generate a new dataset again since the blast loads satisfy the similarity law,and the proposed NNS method can be directly used to simulate the blast loads generated by different cylindrical *** proposed NNS method with high efficiency and accuracy can be used as an effective method to analyze the dynamic response of structures under blast loads,and it has significant application prospects in designing protective structures.

关键词： Close-range air blast load Cylindrical charge Numerical method Neural network CEL method CONWEP model

基于球齿轮的新型轮腿复合式移动平台设计研究

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国防科技大学学报 2008年第4期30卷 98-102页

作者：张湘张立杰潘存云李明宇国防科技大学机电工程及自动化学院湖南长沙410073

复合式移动系统是当前移动机器人研究的热点之一。总结了已有的一些轮-腿复合式移动系统的研究成果及结构特点,提出一种基于球齿轮机构的新型轮-腿复合式移动平台的结构设计方案,这种新型移动平台的轮腿机构具有不同于已有轮-腿复合式... 详细信息

复合式移动系统是当前移动机器人研究的热点之一。总结了已有的一些轮-腿复合式移动系统的研究成果及结构特点,提出一种基于球齿轮机构的新型轮-腿复合式移动平台的结构设计方案,这种新型移动平台的轮腿机构具有不同于已有轮-腿复合式移动系统独特的运动特征,在结构上可实现"轮"、"腿"的真正融合,使得平台具有轮式、腿式和轮-腿复合三种移动模式,可实现直行、斜行、小半径转弯甚至原地转弯等多种运动姿态。对轮腿机构进行了计算机虚拟模型运动仿真研究,并对平台样机进行了姿态调整实验,结果表明这种新型移动平台能够实现设定的多种复杂运动姿态。

关键词：球齿轮轮腿复合式复合式移动系统移动平台轮腿机构

Boosting bidirectional sulfur conversion enabled by introducing boron-doped atoms and phosphorus vacancies in Ni_(2)P for lithium-sulfur batteries

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Journal of Energy Chemistry 2025年第1期100卷 760-769页

作者： lin Peng yu Bai Hang li Meixiu Qu Zhenhua Wang Kening Sun Advanced Research Institute of Multidisciplinary Science Beijing Institute of TechnologyBeijing 100081China Beijing Key Laboratory of Chemical Power Source and Green Catalysis School of Chemistry and Chemical EngineeringBeijing Institute of TechnologyBeijing 100081China

lithium-sulfur (li-S) batteries have gained great attention due to the high theoretical energy density and low cost,yet their further commercialization has been obstructed by the notorious shuttle effect and sluggish redox ***,we supply a strategy to optimize the electron structure of Ni_(2)P by concurrently introducing B-doped atoms and P vacancies in Ni_(2)P (Vp-B-Ni_(2)P),thereby enhancing the bidirectional sulfur *** study indicates that the simultaneous introduction of B-doped atoms and P vacancies in Ni_(2)P causes the redistribution of electron around Ni atoms,bringing about the upward shift of d-band center of Ni atoms and effective d-p orbital hybridization between Ni atoms and sulfur species,thus strengthening the chemical anchoring for lithium polysulfides (liPSs) as well as expediting the bidirectional conversion kinetics of sulfur ***,theoretical calculations reveal that the incorporation of B-doped atoms and P vacancies in Ni_(2)P selectively promotes li2S dissolution and nucleation ***,the li-S batteries with Vp-B-Ni_(2)P-separators present outstanding rate ability of 777 m A h g^(-1)at 5 C and high areal capacity of 8.03 mA h cm^(-2)under E/S of 5μL mg^(-1)and sulfur loading of 7.20 mg cm^(-2).This work elucidates that introducing heteroatom and vacancy in metal phosphide collaboratively regulates the electron structure to accelerate bidirectional sulfur conversion.

关键词： B-doped atoms P vacancies Nickel phosphide Bidirectional sulfur conversion lithium-sulfur batteries