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Improving the thermal shock resistance of ceramics by crack arrest blocks

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Science China(Technological Sciences) 2016年第6期59卷 913-919页

作者： WANG yan Wei XIA Biao su hong hong CHEN Hang FENG Xue Applied Mechanics Laboratory Department of Engineering Mechanics Tsinghua University Center for Mechanics and Materials Tsinghua University Department of Engineering Mechanics Chongqing University

Ceramics used in the high temperature environment are inevitably subjected to sudden temperature change, which may lead to catastrophic thermal shock failure due to the intrinsic brittleness of ceramics. In this paper, an experimental platform is designed to realize the in-situ observation during the thermal shock experiments. Experimental results show that all the cracks initiate from one of the edge midpoints and propagate to another one for square specimens. such experimental observation is consistent with the maximum tensile stress zone with the maximum temperature gradient given by the finite element method(FEM). The different crack modes resulting from different heating rates after thermal shock experiments are observed and analyzed. Comparison between different clamping methods is conducted to study the effects of boundary conditions on the thermal shock experiments. Furthermore, in order to improve the thermal shock performance of alumina ceramics, crack arrest blocks are added near the edge midpoint. The thickness, shape and arrangement of the blocks are systematically investigated to understand the mechanism of improvement of thermal shock resistance.

关键词： thermal shock ultra-high temperature ceramics crack arrest blocks in-situ dynamic observation

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基于干涉和实时前馈实现三个量子节点的纠缠

原子与分子物理学报 2025年第4期42卷 113-120页

作者：刘艳红陈伟李雁翔太原师范学院物理系晋中030619 太原师范学院计算机科学与技术学院晋中030619 山西北方机械制造有限责任公司太原030009

纠缠多个空间分离的远程量子节点是构建量子信息网络的基础,不仅如此,多量子节点间的纠缠亦可应用于分布式量子计算和量子精密测量等,实现更高纠缠度的多量子节点间纠缠势在必行.文中基于干涉和实时前馈,借助于腔增强通过采用受激拉曼... 详细信息

纠缠多个空间分离的远程量子节点是构建量子信息网络的基础,不仅如此,多量子节点间的纠缠亦可应用于分布式量子计算和量子精密测量等,实现更高纠缠度的多量子节点间纠缠势在必行.文中基于干涉和实时前馈,借助于腔增强通过采用受激拉曼散射机制实现三个远距离原子系综的纠缠.该方案中只需要三套腔增强原子系统,光学谐振腔增强了光和原子之间的相互作用,使得通过受激拉曼散射产生的斯托克斯光场和反斯托克斯光场的效率得到提高,实现了高纠缠度的光与原子纠缠.在此前提下,基于斯托克斯光场的干涉和实时前馈实现三个远程原子节点间的纠缠.这种方法可以扩展到更大规模,甚至更加复杂的量子信息网络中,从而在量子信息科学中具有潜在的应用.

关键词：原子系综纠缠干涉实时前馈受激拉曼散射

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地震参数在泌阳凹陷白云岩预测中的应用

新疆石油地质 2004年第2期25卷 153-155页

作者：靳玲丁艳红苏桂芝张玉霞中国石化河南油田勘探开发研究院河南南阳473132

随着储集层预测技术的发展,提取众多的属性参数进行判断已成为地震解释的重要手段,在进行储集层预测和评价时,通常使用与储集层预测有关的各种地震属性,以各种方法从地震数据体中提取的一系列地震属性包含有丰富的地下地质信息,不同的... 详细信息

随着储集层预测技术的发展,提取众多的属性参数进行判断已成为地震解释的重要手段,在进行储集层预测和评价时,通常使用与储集层预测有关的各种地震属性,以各种方法从地震数据体中提取的一系列地震属性包含有丰富的地下地质信息,不同的地震属性值可能与某些地质参数具有很大的相关性,因此利用地震属性参数可以有效地预测岩性和有利储集层,描述油藏特征及孔隙度变化,寻找死油区。描述了地震属性中的振幅、阻抗、频率及能量衰减四种基本类型参数的特征意义,并对泌阳凹陷核二段白云岩区进行了振幅、频率、衰减、阻抗等属性提取分析,成功地预测出白云岩的分布范围。

关键词：地震参数储集层白云岩泌阳凹陷

Expression and significance of HIF-1α and VEGF in rats with diabetic retinopathy

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Asian Pacific Journal of Tropical Medicine 2014年第3期7卷 237-240页

作者： hong-Tao yan Guan-Fang su People's Hospital of Jilin Province Second Hospital of Jilin University

Objective:To investigate the expression of hypoxia inducible iaclor-1α(HIF-1α)and vascular endothelial growth factor(VECF)in diabelic retinopathy(DR)rats and its effect on the DR occurrence and ***:A total of 120 SD rats were randomly divided into trial group and control group with 60 in *** used in the trial group to establish the DM model,citrate buffer salt of same amount was used *** the control group.1,3 and 6 months after injection,respective 20 rats were sacrificed in each group to observe expression of HIF-1αand VEGF in the rat retina tissue at different lime ***:Expression of HIF-1αand VEGF were negative in the control group;expression of HIF-1αand VKGF protein in retinal tissue were weak after 1 month of DR mold *** showed progressive enhancement along with the progression in different organizations,differences between groups were significant(P<0.05).Conclusions:Expressions of HIF-1αand *** were;correlated with disease progression in early diabelic *** oxygen can induce over-expression of HIF-1αand *** shows that HIF-1αand VEGF play an important role in the pathogenesis of DR.

关键词： Diabetes Retina HIF-1α VEGF Expression

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便携式磁弹性传感器检测系统设计

传感器与微系统 2017年第4期36卷 84-86,93页

作者：唐詠廖彦剑罗洪艳苏添进李川刘鑫重庆大学生物工程学院重庆400044

通过对磁弹性传感器检测原理和研究现状分析,设计了一种便携式磁弹性传感器检测系统。采用永磁铁提供静态偏置磁场简化了硬件电路,以STM32嵌入式处理器为控制核心,结合锂电池供电,实现了系统硬件的小型化和低功耗;设计采用了SD卡本地存... 详细信息

通过对磁弹性传感器检测原理和研究现状分析,设计了一种便携式磁弹性传感器检测系统。采用永磁铁提供静态偏置磁场简化了硬件电路,以STM32嵌入式处理器为控制核心,结合锂电池供电,实现了系统硬件的小型化和低功耗;设计采用了SD卡本地存储和低功耗蓝牙无线传输的数据处理方式,并结合上位机进行命令的控制和数据传输。实验表明,检测系统可使磁弹性传感器在不同环境中完成共振频率的测量,另外,设计系统功耗可低至m W级并且在无线传输条件下实现3天以上的连续工作,而且这部分指标仍然有较大的优化空间。由此可见,该系统具有便携式、低功耗、可用于长期监测等优点,可以更好地发挥磁弹性传感器无线、无源、微型化、高灵敏的特点,使其在各领域内得到更广泛的应用。

关键词：磁弹性传感器共振频率 STM32 无线通信便携式

High-energy-density lithium manganese iron phosphate for lithium-ion batteries: Progresses, challenges, and prospects

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Journal of Energy Chemistry 2025年第1期100卷 1-17页

作者： Bokun Zhang Xiaoyun Wang Shuai Wang yan Li Libo Chen Handong Jiao Zhijing Yu Jiguo Tu State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing Research Institute for Intelligent Wearable Systems The Hong Kong Polytechnic University Institute of Advanced Structure Technology Beijing Institute of Technology

The soaring demand for smart portable electronics and electric vehicles is propelling the advancements in high-energy–density lithium-ion *** manganese iron phosphate (LiMnxFe1-xPO4) has garnered significant attention as a promising positive electrode material for lithium-ion batteries due to its advantages of low cost,high safety,long cycle life,high voltage,good high-temperature performance,and high energy *** LiMnxFe1-xPO4has made significant breakthroughs in the past few decades,there are still facing great challenges in poor electronic conductivity and Li-ion diffusion,manganese dissolution affecting battery cycling performance,as well as low tap *** review systematically summarizes the reaction mechanisms,various synthesis methods,and electrochemical properties of LiMnxFe1-xPO4to analyze reaction processes accurately and guide material ***,the main challenges currently faced are concluded,and the corresponding various modification strategies are discussed to enhance the reaction kinetics and electrochemical performance of LiMnxFe1-xPO4,including multi-scale particle regulation,heteroatom doping,surface coating,as well as microscopic morphology ***,in view of the current research challenges faced by intrinsic reaction processes,kinetics,and energy storage applications,the promising research directions are *** importantly,it is expected to provide key insights into the development of high-performance and stable LiMnxFe1-xPO4materials,to achieve practical energy storage requirements.

关键词： Semiconductor doping

Enhanced subacute ischemic stroke treatment via multistage drug delivery system design for combination therapy

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Science China Chemistry 2025年

作者： Xihan Xu Juan-Juan Li Jiamin Li Hui-yan Zhang Yilin Qi Bing-Sen Shi Tianqi Li Shan-Shan su Weitao Zhao Chang Chen Zhongying Gong Huiyu Liu Ke-Rang Wang Dong-Sheng Guo Xue Xue State Key Laboratory of Medicinal Chemical Biology College of Pharmacy Nankai University College of Chemistry State Key Laboratory of Elemento-Organic Chemistry Key Laboratory of Functional Polymer Materials (Ministry of Education) Frontiers Science Center for New Organic Matter Collaborative Innovation Center of Chemical Science and EngineeringNankai University College of Chemistry and Materials Science State Key Laboratory of New Pharmaceutical Preparations and Excipients Key Laboratory of Medicinal Chemistry and Molecular Diagnosis (Ministry of Education) Key Laboratory of Chemical Biology of Hebei Province Hebei Research Center of the Basic Discipline of Synthetic Chemistry Hebei University Department of Neurology Tianjin First Central Hospital School of Medicine Nankai University Beijing Advanced Innovation Center for Soft Matter Science and Engineering State Key Laboratory of Organic-Inorganic Composites Beijing Laboratory of Biomedical Materials Bionanomaterials & Translational Engineering Laboratory Beijing Key Laboratory of BioprocessBeijing University of Chemical Technology

The management of acute ischemic stroke remains challenging due to its abrupt onset and the narrow treatment window,resulting in high rates of disability and *** therapy for neuroprotection and neurorepair strategies provided new hopes for subacute stroke *** we designed a multistage nanodelivery system that matches the unique microenvironment of the subacute phase of stroke,which utilizes calixarene as a building block to effectively load the neuroprotective drug *** calixarene is designed with glycosidic linkages targeting the glucose transporter 1 (GLUT1)on the blood-brain barrier (BBB) and azo bonds that are responsive to hypoxic ***,the decomposed calixarene molecules themselves possess intrinsic bio-activation to modulate inflammatory responses,achieving a multistage therapeutic approach that transitions from targeting to release and finally to *** approach combines anti-inflammation and neuroprotection,providing a multi-level treatment *** system was validated in a rat model of permanent middle cerebral artery occlusion (pMCAO),demonstrating that intravenous administration of the nanodelivery system repairs brain damage and improves motor function 24 h post-pMCAO *** work offers a precise and integrative strategy for stroke patients missing the acute therapy window to improve functional recovery and enhance the effect of comprehensive treatment.

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Lagrangian analysis of the fluid transport induced by the interaction of two co-axial co-rotating vortex rings

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Journal of Hydrodynamics 2020年第6期32卷 1080-1090页

作者： Hai-yan Lin yang Xiang su-yang Qin Hui Xu hong Liu J.C.wu center for aerodynamics school of aeronautics and astronauticsshanghai jiao tong universityshanghai200240china

In this paper,the fluid transport in the interaction of two co-axial co-rotating vortex rings are *** rings are generated using the piston-cylinder apparatus,and the resulting velocity fields are measured using digital particle image *** interaction process is analysed by means of vorticity contour,as well by investigation of the Lagrangian coherent structures(LCSs)defined by the ridges of the finite-time Lyapunov exponent(FTLE).Experimental results demonstrate that two types of vortex interaction are identified,namely strong and weak interactions,*** the strong interaction,the Lagrangian boundaries of the two vortex rings are merged together and form a flux window for fluid *** weak interaction,only the Lagrangian drift induced by the motion of the front vortex ring is observed and affects the Lagrangian boundary of the rear vortex ***,the fluids transported in the strong interaction carry considerable momentum but no *** contrast,there are nearly no fluxes occurring in the weak *** tracking the variations of circulation and impulse occupied by the separated regions distinguished by the LCSs,it is found that the circulation nearly has no change,but the impulse occupied by vortex core region has significant *** the strong interaction,the impulse of rear vortex ring decreases but the impulse of the front vortex ring *** on the impulse law,it is speculated that the fluid force generated by the formation of the rear vortex rings can be ***,the strong interaction between wake vortices can actually improve the propulsive efficiency of the biological systems by operating the formation of large-scale vortices.

关键词： Vortex rings Lagranagian coherent structures(LCSs) fluid transport

A Bayesian expectation maximization algorithm for state estimation of intelligent vehicles considering data loss and noise uncertainty

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Science China Technological Sciences 2025年

作者： yan WANG Feng TIAN Jianqiang WANG Keqiang LI Department of Industrial and Systems Engineering The Hong Kong Polytechnic University School of Vehicle and Mobility Tsinghua University

Sideslip angle, yaw rate, and vehicle velocity are essential for intelligent vehicle control. Since these vehicle states are not measured directly, some Kalman-based approaches have been developed to estimate these states using in-vehicle sensors. However, the existing studies seldom account for the influence of sensor data loss on estimation accuracy. In addition,the process and measurement noise change during the estimation process because of the various driving conditions. To address these problems, an expectation-maximization robust extended Kalman filter (EMREKF) is proposed. Firstly, a robust extended Kalman filter (REKF) is developed to deal with the impact of missing measurements. Then, an improved expectation maximization (EM) algorithm that considers data loss is presented to update the noise parameter of the REKF dynamically. Finally,the improved EM is fused with the REKF to form the EMREKF to estimate vehicle state. The experimental results demonstrate that the EMREKF outperforms EKF, REKF, and maximum correntropy criterion EKF for various degrees of data loss and the proposed algorithm has a strong adaptive ability to different driving conditions.

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