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Functional abnormalities of the glymphatic system in cognitive disorders

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Neural Regeneration Research 2025年第12期20卷 3430-3447页

作者： Wuyue Shentu Qi Kong Yier Zhang Wenyao Li Qiulu Chen Sicheng Yan junjun wang Qilun Lai Qi Xu Song Qiao The Second Clinical Medical College Zhejiang Chinese Medical UniversityHangzhouZhejiang ProvinceChina Department of Neurology Zhejiang HospitalHangzhouZhejiang ProvinceChina Hangzhou TCM Hospital Affiliated to Zhejiang Chinese Medical University HangzhouZhejiang ProvinceChina Department of Neurology Zhejiang Medical&Health Group Hangzhou HospitalHangzhouZhejiang ProvinceChina Department of Neurology Liuzhou People’s HospitalLiuzhouGuangxi Zhuang Autonomous RegionChina Department of Radiology Zhejiang HospitalHangzhouZhejiang ProvinceChina

Various pathological mechanisms represent distinct therapeutic targets for cognitive disorders,but a balance between clearance and production is essential for maintaining the stability of the brain's internal ***,the glymphatic system may represent a common pathway by which to address cognitive *** the established model of the glymphatic system as our foundation,this review disentangles and analyzes the components of its clearance mechanism,including the initial inflow of cerebrospinal fluid,the mixing of cerebrospinal fluid with interstitial fluid,and the outflow of the mixed fluid and the *** section summarizes evidence from experimental animal models and human studies,highlighting the normal physiological properties of key structures alongside their pathological manifestations in cognitive *** same pathologic manifestations of different cognitive disorders appearing in the glymphatic system and the same upstream influences are main points of interest of this *** conclude this article by discussing new findings and outlining the limitations identified in current research progress.

关键词： aquaporin-4 astrocyte cerebrospinal fluid dynamics cognitive disorders glymphatic system

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Al含量对TiZrNbMoAl_(x)难熔高熵合金薄膜高温抗氧化的影响

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表面技术 2025年第1期54卷 53-61,73页

作者：王林青蒲春林张艳王军军重庆理工大学理学院重庆400054 重庆理工大学材料科学与工程学院重庆400054

目的探讨Al含量对TiZrNbMoAl_(x)难熔高熵合金(Refractory High-entropy Alloys,RHEAs)薄膜结构和高温抗氧化性能的影响,并讨论TiZrNbMoAl_(x)RHEAs薄膜的氧化机理。方法利用双靶磁控共溅射技术,以90°扇形的Ti、Zr、Nb、Mo靶拼接而成... 详细信息

目的探讨Al含量对TiZrNbMoAl_(x)难熔高熵合金(Refractory High-entropy Alloys,RHEAs)薄膜结构和高温抗氧化性能的影响,并讨论TiZrNbMoAl_(x)RHEAs薄膜的氧化机理。方法利用双靶磁控共溅射技术,以90°扇形的Ti、Zr、Nb、Mo靶拼接而成的靶材和Al靶材作为溅射靶材,通过调节Al靶溅射功率,制备不同Al含量(原子数分数0%、14%、18%、24%、28%)的TiZrNbMoAl_(x)RHEAs薄膜,并将这些薄膜置于600℃大气环境中进行氧化试验。采用场发射扫描电子显微镜(FESEM)、能量色散光谱仪(EDS)、X射线衍射仪(XRD)和X射线光电子能谱仪(XPS)等,对氧化前后薄膜的物相组成和微观结构进行分析。对比不同Al含量的TiZrNbMoAl_(x)RHEAs薄膜的抗氧化性能,并分析其氧化机理。结果薄膜的微观结构和高温抗氧化性能与Al含量密切相关。不含Al时,薄膜呈现出(110)择优取向的BCC单相固溶体结构;Al原子数分数为14%~24%时,薄膜表现为无定形相结构;Al含量较高(原子数分数为28%)时,薄膜中出现了AlZr_(3)二次相。在600℃环境退火后,Al氧化生成了Al_(2)O_(3),这有效提升了TiZrNbMoAl_(x)RHEAs薄膜的抗氧化性能。然而,过量的Al含量(原子数分数为28%)会导致应力集中并产生裂纹,降低薄膜的高温抗氧化性能。结论Al含量对TiZrNbMoAl_(x)RHEAs薄膜的高温抗氧化性能具有重要影响,适量的Al含量可改善TiZrNbMoAl_(x)RHEAs薄膜的抗氧化性能。

关键词：难熔高熵合金薄膜高温抗氧化性能 Al含量相组成微观结构

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近距离煤层群采空区下切眼掘进及支护技术研究

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能源与节能 2025年第1期 201-203,207页

作者：王军军山西汾西矿业集团南关煤业有限责任公司山西晋中031300

为确保近距离煤层群开采下部工作面切眼安全掘进,以5303采煤工作面切眼为研究对象,结合现场情况针对性提出切眼掘进及支护安全技术,并进行工程应用。在5303采煤工作面切眼掘进期间,通过层间距(切眼与上覆采空区间)持续探测、切眼顶板注... 详细信息

为确保近距离煤层群开采下部工作面切眼安全掘进,以5303采煤工作面切眼为研究对象,结合现场情况针对性提出切眼掘进及支护安全技术,并进行工程应用。在5303采煤工作面切眼掘进期间,通过层间距(切眼与上覆采空区间)持续探测、切眼顶板注浆及分次掘进方式确保大断面切眼掘进安全;通过锚网索、单体+工字钢架棚方式维护大跨度切眼围岩稳定。工程应用后,5303采煤工作面切眼得以安全高效掘进,切眼围岩变形量较小,表明现场采用的掘进及支护技术可满足近距离采空区下大跨度切眼施工需要。

关键词：近距离煤层群大断面切眼围岩支护顶板注浆

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破碎围岩条件下巷道支护技术研究

能源与节能 2025年第2期 212-214+281页

作者：王军军山西汾西矿业集团南关煤业有限责任公司

为实现破碎围岩条件下巷道的有效支护，以7503工作面运输巷为工程实例，分析了原支护技术存在的问题，综合采用“锚杆+中空注浆锚索+金属网+喷浆+注浆管”方式控制破碎围岩。依据7503工作面运输巷现场条件，给出了围岩破碎区的支护参数... 详细信息

为实现破碎围岩条件下巷道的有效支护，以7503工作面运输巷为工程实例，分析了原支护技术存在的问题，综合采用“锚杆+中空注浆锚索+金属网+喷浆+注浆管”方式控制破碎围岩。依据7503工作面运输巷现场条件，给出了围岩破碎区的支护参数，并分析了围岩的控制效果。工程应用后，围岩破碎区7503工作面运输巷顶板、底板、左帮、右帮最大变形量分别为96、 155、 52、 49 mm，各测点巷道断面收缩率均在5.5%以内，围岩变形量整体较小，可满足后续使用需求。

关键词：破碎围岩巷道支护中空注浆锚索围岩加固

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Stability of stochastic differential equation with linear fractal noise

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Frontiers of Mathematics in China 2014年第3期9卷 495-507页

作者： junjun LIAO Xiangjun wang School of Mathematics and Statistics Huazhong University of Science and TechnologyWuhan 430074 China

We study a class of stochastic differential equation with linear fractal noise. By an auxiliary stochastic differential equation, we prove the existence and uniqueness of the solution under some mild assumptions. We a... 详细信息

关键词： Fractional Brownian motion (FBM) stochastic differential equation (SDE) exponential p-stability λ-exponential p-stability

UNCONDITIONAL SUPERCONVERGENCE ANALYSIS OF AN Ri-GALERKIN MIXED FINITE ELEMENT METHOD FOR TWO-DIMENSIONAL GINZBURG-LANDAU EQUATION

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Journal of Computational Mathematics 2019年第4期37卷 437-457页

作者： Dongyang Shi junjun wang School of Mathematics and Statistics Zhengzhou University Zhengzhou 450001 China

An H^1-Galerkin mixed finite element method (MFEM) is discussed for the two-dimensional Ginzburg-Landau equation with the bilinear element and zero order Raviart-Thomas elemen t (Q11+Q10×Qo01). A linearized Crank-Nicolson fully-discrete scheme is developed and a time-discrete system is introduced to split the error into two parts which are called the temporal error and the spatial error, respectively. On one hand, the regularity of the time-discrete system is deduced through the temporal error estimation. On the other hand, the superconvergent estimates of u in H^1-norm and →q in H(div;Ω)-norm with order 0(h^2+τ^2) are obtained unconditionally based on the achievement of the spatial result. At last, a numerical experiment is included to illustrate the feasibility of the proposed method. Here, h is the subdivision parame ter and τ is the time step.

关键词： The two-dimensional Ginzburg-Landau equation H^Galerkin MFEM Temporal and spatial errors Unconditionally Superconvergent resillts

Synthesis of Fluorinated Urchin-like Serried Hydroxyapatite with Improved Water Sorption-Solubility and Bioactivity for Dental Composites

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Chemical Research in Chinese Universities 2021年第5期37卷 1092-1100页

作者： CHEN Hongyan wang junjun wang Ruili ZHU Meifang State Key Laboratory for Modification of Chemical Fibers and Polymer Materials International Joint Laboratory for Advanced Fiber and Low-dimension MaterialsCollege of Materials Science and EngineeringDonghua UniversityShanghai201620P.R.China

Fluorine is present in the hydroxyapatite mineral in natural tooth enamel,which plays a key role in the prevention of dental *** aim of this study is to synthetize the fluorinated urchin-like serried hydroxyapatite(FnUHA)particles with different degrees of fluorine substitution and explore the effect of the fluorine element on the water absorption-solubility,mechanical strength,and biological activity of dental composites.

关键词： fluorine prevention element

UNCONDITIONALLY SUPERCLOSE ANALYSIS OF A NEW MIXED FINITE ELEMENT METHOD FOR NONLINEAR PARABOLIC EQUATIONS

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Journal of Computational Mathematics 2019年第1期37卷 1-17页

作者： Dongyang Shi Fengna Yan junjun wang School of Mathematics and Statistics Zhengzhou UniversityZhengzhou 450001China

This paper develops a framework to deal with the unconditional superclose analysis of nonlinear parabolic *** the finite dement pair Q11/Q01×Q10 as an example, a new mixed finite element method (FEM)is established and the r-independent superclose results of the original variable u in Hi-norm and the flux variable q=-a(u)■u in L^2- norm are deduced (τ is the temporal partition parameter).A key to our analysis is all error splitting technique,with which the time-discrete and the spatial-discrete systems are constructed,*** the first system,tile boundedness of the temporal errors are *** the second system,the spatial superclose results are presented *** the previous literature always only obtain the convergent estimates or require certain time step ***,some numerical results are provided to confirm the theoretical analysis,and show the efficiency of the proposed method.

关键词： Nonlinear parabolic equation Mixed FEM Time-discrete and spatial-discrete systems τ-independent superelose results

Electric Field Distribution of Soluble Salt Deposition on the Surface of Insulators in Railway Overhead Lines

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Chinese Journal of Electrical Engineering 2022年第3期8卷 123-132页

作者： Sihua wang junjun wang Long Chen Lei Zhao School of Automation&Electrical Engineering Lanzhou Jiaotong UniversityLanzhou 730070China Rail Transit Electrical Automation Engineering Laboratory of Gansu Province Lanzhou Jiaotong UniversityLanzhou 730070China

Different constituents of soluble salts have different effects on the insulation performance of *** study the electric field distribution of soluble salt deposition on the surface of high-speed railway insulators,a two-dimensional model of the cantilever insulator electrostatic field and constant-current field with soluble salt deposition is *** simulation results indicate that the relative dielectric constant of dry pollution is the main factor that affects the electric field distribution on the surface of the *** electric field intensity is arranged in the following order:CaSO_(4)>KNO_(3)>NaNO_(3)>K_(2)SO_(4)>NaCl>MgSO_(4),and the conductivity of each dirty liquid in the wet state becomes a key factor affecting the electric field distribution,which is specifically shown as sodium chloride>nitrate>*** simulation results are compared with existing test results to verify that they were *** is also found that the electric field intensity of the insulator with good hydrophobicity is slightly greater than that of the insulator without *** results provide a theoretical basis for the classification of regional pollution levels and the testing of insulator contamination in the laboratory.

关键词： Catenary insulator soluble salt composition electric field intensity electrostatic field constant-current field