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Synthesis of Polynorbornene-Poly(ethylene-co-propylene)Diblock Copolymer

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Chinese Chemical Letters 1998年第5期9卷 447-450页

作者： Wu, q wen, q Lu, ZJ Zhongshan Univ Inst Polymer Sci Canton 510275 Peoples R China

Transformation of living ring-opening metathesis polymerization into coordination polymerization by converting the titanacyclobutane group attached to a polynorbornene chain into titanocene alkoxide has been used for the synthesis of polynorbornene-poly(ethylene-co-propylene) block copolymer. Preliminary characterizations of the copolymerization products by solvent extraction and C-13 nMR spectrum are reported.

关键词： ring-opening metathesis polymerization coordination polymerization diblock copolymer norbornene ethylene propylene

Acute and chronic excitotoxicity in ischemic stroke and late-onset Alzheimer's disease

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neural Regeneration Research 2025年第7期20卷 1981-1988页

作者： Shan Ping Yu Emily Choi Michael qJiang Ling Wei Department of Anesthesiology Emory University School of MedicineAtlantaGAUSA Center for Visual and neurocognitive Rehabilitation Atlanta Veterans Affairs Medical CenterDecaturGAUSA

Stroke and Alzheimer's disease are common neurological disorders and often occur in the same *** comorbidity of the two neurological disorders represents a grave health threat to older *** review presents a brief background of the development of novel concepts and their clinical *** activity of glutamatergic n-methyl-D-aspartate receptors and n-methyl-D-aspartate receptor-mediated Ca^(2+)influx is critical for neuronal *** ischemic insult induces prompt and excessive glutamate release and drastic increases of intracellular Ca^(2+)mainly via n-methyl-D-aspartate receptors,particularly of those at the extrasynaptic *** Ca^(2+)-evoked neuronal cell death in the ischemic core is dominated by necrosis within a few hours and days known as acute ***,mild but sustained Ca^(2+)increases under neurodegenerative conditions such as in the distant penumbra of the ischemic brain and early stages of Alzheimer's disease are not immediately toxic,but gradually set off deteriorating Ca^(2+)-dependent signals and neuronal cell loss mostly because of activation of programmed cell death *** on the Ca^(2+)hypothesis of Alzheimer's disease and recent advances,this Ca^(2+)-activated“silent”degenerative excitotoxicity evolves from years to decades and is recognized as a unique slow and chronic *** n-methyl-D-aspartate receptor subunit Glun3A,primarily at the extrasynaptic site,serves as a gatekeeper for the n-methyl-D-aspartate receptor activity and is neuroprotective against both acute and chronic *** stroke and Alzheimer's disease,therefore,share an n-methyl-D-aspartate receptor-and Ca^(2+)-mediated mechanism,although with much different time *** is thus proposed that early interventions to control Ca^(2+)homeostasis at the preclinical stage are pivotal for individuals who are susceptible to sporadic late-onset Alzheimer's disease and Alzheimer's disease-related

关键词： Ca^(2+)hypothesis cognitive deficits hyperactivity late-onset Alzheimer's disease neurodegeneration n-methyl-D-aspartate receptors n-methyl-D-aspartate receptor subunits pathogenesis preventive treatment

Synthesis and mesomorphic properties of n-butyl-4- [4-((4-n-alkoxyl-tetrafluorophenyl)ethynyl)benzyloxy]benzoates

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Chinese Journal of Chemistry 1995年第6期13卷 515-519页

作者： wen, JX Yin, HY Chen, q CHInESE ACAD SCI SHANGHAI INST ORGAN CHEMSHANGHAI 200032PEOPLES R CHINA

A homologous series of n-butyl-4-[4-((4-n-alkoxyl-tetrafluorophenyl)ethynyl)benzyloxy] benzoates have been synthesized. Their phase transition temperatures have also measured by polarizing textural observation and con... 详细信息

关键词： liquid crystal synthesis mesomorphic properties

Cascaded Sliding-mode Observer and Its Applications in Output Feedback Control Part I:Observer Design and Stability Analysis

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CSEE Journal of Power and Energy Systems 2021年第2期7卷 295-306页

作者： Tianhao wen Yang Liu q.H.Wu Luonan qiu School of Electric Power Engineering South China University of TechnologyGuangzhou 510640China

This paper proposes a cascaded sliding-mode observer for systems with high relative degree and studies its applications in output feedback controller *** part I,the working principle and parameter design of the proposed observer are discussed in *** is proved that,within a sufficiently short period of time,the states of the proposed observer will reach the intersection of all the sliding *** sliding surfaces,the observation error of the proposed observer will converge to sufficiently small *** with traditional high-gain observers,the proposed observer has smaller gain *** addition,the peaking-phenomenon occurred in the proposed observer is less ***,the proposed observer has a convergence rate of observation error as fast as that of traditional high-gain *** studies are carried out on a fifth-order system to verify the properties of the proposed observer.

关键词： Sliding-mode observer stability output feedback control

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惩罚对齐法:测量不变性检验的新方法

心理科学进展 2025年第1期33卷 176-190,I0008-I0013页

作者：温聪聪厦门大学国际学院厦门361005

Asparouhov和Muthén在2023年提出了一种全新的惩罚结构方程模型框架。惩罚对齐法是该模型框架在测量不变性检验领域的应用范例。惩罚对齐法继承了多组探索性因子分析在探索性因子分析框架内进行测量不变性检验和可以估计交叉载荷等优点... 详细信息

Asparouhov和Muthén在2023年提出了一种全新的惩罚结构方程模型框架。惩罚对齐法是该模型框架在测量不变性检验领域的应用范例。惩罚对齐法继承了多组探索性因子分析在探索性因子分析框架内进行测量不变性检验和可以估计交叉载荷等优点,继承了对齐法使用成分损失函数、允许模型中存在一定量不等参数等优点,同时继承了贝叶斯结构方程模型对模型参数设置先验分布、通过检验模型参数的近似测量不变性达到潜因子均值比较的目的等优点。此外,惩罚对齐法还克服了传统测量不变性检验方法的一些不足。本文以大学生职业价值观研究为例,比较了多组验证性因子分析、基于验证性因子分析的惩罚对齐法分析、基于探索性结构方程模型的惩罚对齐法分析拟合样本数据的效果,演示了如何使用惩罚对齐法进行测量不变性检验和多组比较。

关键词：测量不变性检验惩罚对齐法贝叶斯结构方程模型探索性结构方程模型对齐先验分布

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A novel friction stir diffusion bonding process using convex-vortex pin tools

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Journal of Materials Science & Technology 2020年第13期47卷 23-30页

作者： S.D.Ji q.wen Z.W.Li College of Aerospace Engineering Shenyang Aerospace UniversityShenyang 110136China State Key Laboratory of Advanced Welding and Joining Harbin Institute of TechnologyHarbin 150001China

In this work,a novel friction stir diffusion bonding(FSDB)method was proposed to eliminate hook when joining thin *** tools,with several convex-vortex pins were innovatively designed to improve the diffusion bonding effect of the lap *** showed that sound joints,excellently bonded at the lap interface and without hook,were *** lap interfaces on the joints welded using the T-tool and F-tool almost remained intact,thereby indicating that they were formed by diffusion *** material flow behavior was also simulated by FLUEnT software and the results showed that the material flow along thickness was significantly enhanced by increasing the pin *** joint welded by the T-tool showed shear fracture *** bonding was formed at the lap interface when using the F-tool and thus the joint showed tensile fracture.

关键词： Friction stir diffusion bonding Convex-vortex pin Hook Material flow Failure

Intelligent interaction system based on multimodal conformal triboelectric nanogenerator patch for disabled sports and life

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Science China Technological Sciences 2025年

作者： Yuzhang wen Mengqi ZHAnG Zhenning XIE Zida An Bing LIU Fengxin SUn Tianming ZHAO Zuojun YU Fei WAnG Yupeng MAO Physical Education Department Northeastern University(Shenyang) Faculty of Robot Science and Engineering Northeastern University Criminal Investigation Police University of China State Key Laboratory of Robotics Shenyang Institute of Automation Chinese Academy of Sciences China Ice Sports College Beijing Sport University

Intelligent interaction technology based on advanced sensing units has become a research hotspot. In this paper, an intelligent interaction system (IIS) based on a multimodal conformal triboelectric nanogenerator patch (MCTP) is reported for sports monitoring and life promotion of the disabled. This IIS consists of a cloud-based smart sports recognition program and a smart life application. The porous micro-reinforced structure of polyurethane (PU) Sponge&Ecoflex, and the surface modification of PTFE by coating it with MXene endows the MCTP with excellent electrical properties. It shows good angle and force sensitivities of 1.1 V/°and 1.61 V/n, respectively, and has an ultra-fast response time of 15 ms, meeting the needs of human motion monitoring. The MCTP can also capture the mechanical energy, producing a maximum output power of 139μ*** with the commercial inertial measuring unit (IMU), the MCTP shows better consistency in human joint angle sensing. A precise analysis of wheelchair curling sports monitoring points is achieved by combining the MCTP and the human anatomy model. The cloud-based smart sports recognition program utilizes machine learning to achieve visual feedback on the three throwing technologies of draw, takeout and clearing. In addition, the developed smart life application uses a highsensitivity MCTP-sensor array design to achieve a variety of smart home interactions through simple finger touches. Overall,the IIS integrates the three major functions of smart sports sensing, energy capture, and smart home control, providing important application prospects in the fields of smart sports and human-computer interaction for the disabled.

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Explicit Stationary Distribution of the(L,1)-reflecting Random Walk on the Half Line

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Acta Mathematica Sinica,English Series 2014年第3期30卷 371-388页

作者： wen Ming HOnG Ke ZHOU Yi qiang q.ZHAO School of Mathematical Sciences & Laboratory of Mathematics and Complex Systems Beijing Normal University School of Mathematics and Statistics Carleton University

In this paper,we consider the（L,1） state-dependent reflecting random walk（RW） on the half line,which is an RW allowing jumps to the left at a maximal size *** this model,we provide an explicit criterion for（positive） recurrence and an explicit expression for the stationary *** an application,we prove the geometric tail asymptotic behavior of the stationary distribution under certain *** main tool employed in the paper is the intrinsic branching structure within the（L,1）-random walk.

关键词： Random walk multi-type branching process recurrence positive recurrence stationarydistribution tail asymptotic

Sol-gel derived HA/TiO_2 double coatings on Ti scaffolds for orthopaedic applications

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中国有色金属学会会刊：英文版 2006年第B1期16卷 209-216页

作者： XU W HU W Y LI M H MA q q P. D. HODGSOn wen C E Department of Applied Physics Hunan University Changsha 410082 China Centre for Material and Fibre Innovation Deakin University Geelong Vic 3217 Australia

Hydroxyapatite/titania (HA/TiO2) double layers were coated onto Ti scaffolds throughout for orthopaedic applications by sol-gel method. Differential scanning calorimetry (DSC), thermogravimetric analysis (TG) and X-ray diffractometry (XRD) were used for the characterisation of the phase transformations of the dried gels and coated surface structures. Scanning electron microscope (SEM) equipped with energy dispersive spectrometry (EDS) was used for the observation and evaluation of the morphology and phases of the surface layers and for the assessment of the in vitro tests. The in vitro assessments were performed by soaking the HA/TiO2 double coated samples into the simulated body fluid (SBF) for various periods. The TiO2 dipping-coating method at a speed of 12 cm/min, followed by a heat treatment at 600 ℃ for 20 min. The HA la lyaeyre wr wasa ssu cbosaetqeude bnytl ya dipping-coated on the outer surface at the same speed and then heat-treated at difference temperatures. The results indicat that the HA phase begins to crystallize after a heat treatment at 560 ℃. The crystallinity increases obviously at 760 ℃. SEM observations find no delamination or crack at the interfaces of HA/TiO2 and TiO2/Ti. The HA/TiO2 coated Ti scaffolds displays excellent bone-like apatite forming ability when it is soaked into SBF. Ti scaffolds after HA/TiO2 double coatings can be anticipated as promising implant materials for orthopaedic

关键词：钛支架溶胶-凝胶法羟基磷灰石/二氧化钛涂层医学整形外科应用