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Communications in Theoretical Physics 2007年第2期47卷 235-243页

作者： PANG Xiao-feng yu jia-feng Institute of Life Science and Technology University of Electronic Science and Technology Chengdu 610054 China International Centre for Materials Physics the Chinese Academy of Sciences Shenyang 110015 China

The dynamic properties of proton conductivity along hydrogen-bonded molecular systems, for example, ice crystal, with structure disorder or damping and finite temperatures exposed in an externally applied electric-field have been numerically studied by Runge-Kutta way in our soliton model. The results obtained show that the proton-soliton is very robust against the structure disorder including the fluctuation of the force constant and disorder in the sequence of masses and thermal perturbation and damping of medium, the velocity of its conductivity increases with increasing of the externally applied electric-field and decreasing of the damping coefficient of medium, but the proton-soliton disperses for quite great fluctuation of the ＂force constant and damping coefficient. In the numerical simulation we find that the proton-soliton in our model is thermally stable in a large region of temperature of T ≤ 273 K under influences of damping and externally applied electric-field in ice crvstal. This shows that our model is available and appropriate to ice.

关键词： proton conductivity structure disorder temperature hydrogen bonded system

数字金融发展对农民可持续性增收的影响机制——基于湖北省数据的实证分析

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安徽农业科学 2024年第11期52卷 205-208,213页

作者：方梦雪余家凤长江大学经济与管理学院湖北荆州434023

基于2011—2021年湖北省13个市(州)的面板数据,构建固定效应模型和中介效应模型,实证分析湖北省数字金融对农民可持续性增收影响机制。结果表明:湖北省发展数字金融能提高农民收入水平、改善农民收入结构,可以显著地促进农民可持续性增... 详细信息

基于2011—2021年湖北省13个市(州)的面板数据,构建固定效应模型和中介效应模型,实证分析湖北省数字金融对农民可持续性增收影响机制。结果表明:湖北省发展数字金融能提高农民收入水平、改善农民收入结构,可以显著地促进农民可持续性增收,且对低收入水平、低收入可持续性的农民效果更佳;地区经济增长对湖北省数字金融提高农民收入水平、使农民收入增加具有可持续性均存在部分中介效应,其值分别为39.69%和40.96%。此外,推进城镇化建设对农民可持续性增收也有显著的促进作用。

关键词：数字金融发展农民可持续性增收固定效应模型中介效应

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铁死亡发生机制及其对几种重大慢性疾病的影响

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实用中西医结合临床 2024年第9期24卷 118-122页

作者：许俊申俞佳峰王亚敏张娣胡翠李雪江西省中医药研究院南昌330046

铁死亡,由2012年Dixon等[1]发现并命名的一种新型的细胞死亡方式,主要是由铁离子积累和脂质过氧化所导致且具有铁依赖的非凋亡形式细胞死亡[2],在形态学与生物学等方面与细胞凋亡、焦亡和坏死等方式均不一样。有研究表明,铁死亡和细胞... 详细信息

铁死亡,由2012年Dixon等[1]发现并命名的一种新型的细胞死亡方式,主要是由铁离子积累和脂质过氧化所导致且具有铁依赖的非凋亡形式细胞死亡[2],在形态学与生物学等方面与细胞凋亡、焦亡和坏死等方式均不一样。有研究表明,铁死亡和细胞凋亡可能协同促进细胞的死亡[3]。

关键词：铁死亡发生机制重大慢性疾病

Effect of Sc on Al_(3)Fe phase and mechanical properties of as-cast AA5052 aluminum alloy

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China Foundry 2024年第3期21卷 257-264页

作者： Yang Li Qing yu feng-feng Chen jia-wen He Hong-mei Yang Meng-nie Li Faculty of Materials Science and Engineering Kunming University of Science and TechnologyKunming 650093China

The AA5052 aluminum alloy is widely used in automobile and aerospace manufacturing,and with the development of light-weight alloys,it is required that these materials exhibit better mechanical *** studies have demonstrated that the addition of Sc to aluminum alloys can improve both the microstructure and properties of the *** this study,the effect of Sc on the Fe-rich phase and properties of the AA5052 aluminum alloy was studied by adding 0%,0.05%,0.2%,and 0.3%*** results show that with the increase of Sc,the coarse needle-like Fe-rich phase gradually transforms into Chinese-script and then nearly spherical particles,reduce the size of Fe-rich phase,and refine the grain with increase of high angle grain boundaries(HAGBs).These microstructure changes enhance the strength of the AA5052 alloy through Sc *** ductility of the alloy is obviously improved because the addition of a lower amount of Sc changes the morphology of Fe-rich phase from needle-like into a Chinese-script,and it is subsequently reduced as a result of significant increase in HAGBs with increasing Sc content.

关键词： AA5052 aluminum alloy Al3Fe phase mechanical properties grain boundary

Sedimentary architecture of submarine channel-lobe systems under different seafloor topography:Insights from the Rovuma Basin offshore East Africa

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Petroleum Science 2024年第1期21卷 125-142页

作者： Mei Chen Sheng-He Wu Rui-feng Wang jia-jia Zhang Peng-Fei Xie Min Wang Xiao-feng Wang Ji-Tao yu Qi-Cong Xiong State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Beijing)Beijing102249China College of Geosciences China University of Petroleum(Beijing)Beijing102249China Faculty of Geosciences University of BremenBremen28359Germany MARUM-Center for Marine and Environmental Sciences University of BremenBremen28359Germany Research institute of Petroleum Exploration and Development PetroChinaBeijing10083China School of Geosciences Yangtze UniversityWuhan 100083HubeiChina CNODC Mozambique Ltd. Beijing 100034China

Seafloor topography plays an important role in the evolution of submarine ***,it is still not so clear how the shape of slope affects the three-dimensional(3-D)architecture of submarine *** this study,we analyze the effect of topography factors on different hierarchical lobe architectures that formed during Pliocene to Quaternary in the Rovuma Basin offshore East *** characterize the shape,size and growth pattern of different hierarchical lobe architectures using 3-D seismic *** find that the relief of the topographic slope determines the location of preferential deposition of lobe complexes and single *** the topography is irregular and presents topographic lows,lobe complexes first infill these *** lobes are deposited preferentially at positions with higher longitudinal(***-slope)slope *** the longitudinal slope becomes higher,the aspect ratio of the single lobes ***(***-slope)topography does not seem to have a strong influence on the shape of single lobe,but it seems to affect the overlap of single *** the lateral slope gradient is relatively high,the single lobes tend to have a larger overlap ***,as the average of lateral slope and longitudinal slope gets greater,the width/thickness ratio of the single lobe is smaller,*** tend to accumulate *** results demonstrate that the shape of slopes more comprehensively influences the 3-D architecture of lobes in natural deep-sea systems than previously other lobe deposits and analogue experiments,which helps us better understand the development and evolution of the distal parts of turbidite systems.

关键词： Submarine fan Seafloor topography Sedimentary architecture Slope system SW Indian ocean

Regeneration of the heart:f rom molecular mechanisms to clinical therapeutics

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Military Medical Research 2024年第1期11卷 80-97页

作者： Qian-yun Guo jia-Qi Yang Xun-Xun feng yu-Jie Zhou Beijing Key Laboratory of Precision Medicine of Coronary Atherosclerotic Disease Beijing Institute of Heart Lung and Blood Vessel DiseaseClinical Center for Coronary Heart DiseaseDepartment of CardiologyBeijing Anzhen HospitalCapital Medical UniversityBeijing 100029China

Heart injury such as myocardial infarction leads to cardiomyocyte loss,fibrotic tissue deposition,and scar *** changes reduce cardiac contractility,resulting in heart failure,which causes a huge public health *** personnel,compared with civilians,is exposed to more stress,a risk factor for heart diseases,making cardiovascular health management and treatment innovation an important topic for military *** far,medical intervention can slow down cardiovascular disease progression,but not yet induce heart *** the past decades,studies have focused on mechanisms underlying the regenerative capability of the heart and applicable approaches to reverse heart *** have emerged from studies in animal models and early clinical *** interventions show the potential to reduce scar formation and enhance cardiomyocyte proliferation that counteracts the pathogenesis of heart *** this review,we discuss the signaling events controlling the regeneration of heart tissue and summarize current therapeutic approaches to promote heart regeneration after injury.

关键词： Heart regeneration Cardiac disease Therapeutics Signaling mechanisms

LAMDA-SSL:a comprehensive semi-supervised learning toolkit

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Science China(Information Sciences) 2024年第1期67卷 306-307页

作者： Lin-Han jia Lan-Zhe GUO Zhi ZHOU yu-feng LI National Key Laboratory for Novel Software Technology Nanjing University

Machine learning, particularly deep learning, has achieved remarkable success across a wide range of tasks. However,most of these tasks demand a substantial amount of labeled training data, which can be challenging to obtain in many real-world applications due to difficulties, costs, or time constraints associated with labeling. In this context,semi-supervised learning (SSL) has emerged as a promising paradigm to alleviate the dependency on large labeled datasets by harnessing the power of unlabeled data [1–3].

关键词：

Nanoscopic tribological characteristics of a cryogenically cycled Zr-based metallic glass

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Science China(Physics,Mechanics & Astronomy) 2024年第6期67卷 113-126页

作者： Qian jia Qiaosheng Xia Qing Zhou yucheng Wang yue Ren yu Meng Haifeng Wang feng Zhou State Key Laboratory of Solidification Processing Center of Advanced Lubrication and Seal MaterialsNorthwestern Polytechnical UniversityXi’an 710072China Shaanxi Key Laboratory of Surface Engineering and Remanufacturing Xi’an UniversityXi’an 710065China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China

Optimized macroscopic tribological behavior can be anticipated in metallic glasses(MGs)by cryogenic cycling treatment(CCT),which is attributed to enhanced ***,the intrinsic friction mechanisms of MGs induced by cryogenic rejuvenation are still poorly *** the present study,nanoscopic wear tests were conducted on the Zr-based MGs surface with different CCT cycles using atomic force microscopy(AFM).After CCT treatment with 100 cycles,the MG displays the highest adhesion and ploughing frictions,but significantly improved anti-wear *** tests and molecular dynamics simulations disclose that the increased adhesion is attributed to the dominance of liquid-like regions in the CCT-treated MGs,and the impact of reduced hardness and weak elastic recovery results in the deteriorated ploughing *** enhanced plasticity effectively dissipates the strain from the AFM tip through multiple shear bands and weakens the adhesion during deformation,giving rise to excellent wear *** study elucidates the promoting effect of CCT on the outstanding antiwear performance of MGs,and is helpful for the development of novel alloys.

关键词： metallic glasses cryogenic cycling treatment nanoscope wear friction mechanism

Swelling of Spherical Polyelectrolyte Gels

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Chinese Journal of Polymer Science 2024年第9期42卷 1386-1392,I0009页

作者： Ming-yu Duan jia-Dong Chen Yi-Ming Liu Zhao-feng Peng Guang Chen Department of Advanced Manufacturing and Robotics College of EngineeringPeking UniversityBeijing 100871China

Polyelectrolyte(PE)gels,distinguished by their unique stimuli-responsive swelling behavior,serve as the basis of broad applications,such as artificial muscles and drug *** this work,we present a theoretical model to analyze the electrostatics and its contribution to the swelling behavior of PE gels in salt *** minimizing the free energy of PE gels,we obtain two distinct scaling regimes for the swelling ratio at equilibrium with respect to the salt *** compare our predictions for the swelling ratio with experimental measurements,which show excellent *** addition,we employ a finite element method to assess the applicability range of our theoretical model and *** anticipate that our model will also provide valuable insights into drug adsorption and release,deformation of red blood cells,4D printing and soft robotics,where the underlying mechanism of swelling remains enigmatic.

关键词： Gels Polyelectrolytes Swelling Stimuli-responsive Electrostatic interaction Cell model

A guidance and control design with reduced information for a dual-spin stabilized projectile

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Defence Technology（防务技术） 2024年第3期33卷 494-505页

作者： yu Wang Jiyan yu Xiaoming Wang jia Fangxiu Intelligent Ammunition Technology National Defense Key Discipline Laboratory Nanjing University of Science and TechnologyNanjingJiangsu210094China

In this paper,an integrated guidance and control method based on an adaptive path-following controller is proposed to control a spin-stabilized projectile with only translational motion information under the constraint of an actuator,uncertainties in aerodynamic parameters and measurements,and control system *** to the fairly high rotation speed,the dynamic model of this missile is strongly nonlinear,uncertain and coupled in pitch,yaw and roll channels.A theoretical equivalent resultant force and uncertainty compensation method are comprehensively used to realize decoupling of pitch and *** response to the strong nonlinear and time-varying characteristics of the dynamic system,the quasi-linear model whose parameters are obtained by interpolation of points selected as the segmentation points in the trajectory envelope,is used for calculation in each *** cope with the system uncertainty caused by model approximation,parameter uncertainty and ballistic interference,an extended state estimator is used to compensate the output feedback according to the test ballistic *** order to improve the tracking efficiency and ensure the tracking error convergence with only translational motion information,the virtual guide point,whose derivative is deduced according to the Lyapunov principle,is calculated in real time according to the projection relationship between the real-time position and the reference trajectory,and a virtual line-of-sight angle and the backstepping method are used for the design of the guidance and control *** order to avoid the influence of control input saturation on the guidance and control performance due to the actuator limitation and improve the robustness of the system,an anti-saturation compensator is designed according to the two-step *** feasibility and effectiveness of the path-following controller is verified through closed-loop flight simulations with measurement,control,and condition *** result

关键词： Spin-stabilized projectile Reduced information Path-following control Extended state observer Coupled nonlinear system Input saturation