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大深宽比矩形高层建筑表面脉动风压非高斯特性

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哈尔滨工业大学学报 2025年第1期57卷 46-55页

作者：袁家辉陈水福刘奕中冶南方城市建设工程技术有限公司武汉430063 浙江大学建筑工程学院杭州310058

为探究大深宽比矩形高层建筑表面脉动风压的非高斯特性,本文对深宽比为1/9~9的矩形高层建筑进行了同步测压风洞试验。基于试验结果,分析了建筑表面风压的三阶和四阶统计矩分布特性,对高层建筑各立面风压进行高斯与非高斯分布的分区;研... 详细信息

为探究大深宽比矩形高层建筑表面脉动风压的非高斯特性,本文对深宽比为1/9~9的矩形高层建筑进行了同步测压风洞试验。基于试验结果,分析了建筑表面风压的三阶和四阶统计矩分布特性,对高层建筑各立面风压进行高斯与非高斯分布的分区;研究了风压的空间相关系数与非高斯性强度的关系,提出了一种新的估算建筑侧风面平均再附长度的计算方法。结果表明:在建筑侧风面上,脉动风压服从高斯还是非高斯分布取决于测点到迎风前缘的距离;除了以往文献指出的迎风面角部、侧风面分离区和背风面风压呈现非高斯性外,再附区后面的风压也呈现出高度的非高斯性;本文提出的相关系数法在计算平均再附长度时具有良好的准确性,利用该方法获得了矩形高层建筑侧风面的平均再附长度沿高度的变化呈抛物线形状。

关键词：矩形高层建筑非高斯特性风洞试验相关系数平均再附长度

木犀草素改善脊髓损伤大鼠血清诱导的心肌细胞死亡

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中国组织工程研究 2025年第1期29卷 38-43页

作者：张稳稳徐梦如田园张立飞师姝王宁原媛王丽郝海虎山西中医药大学第一临床学院山西省晋中市030600 山西医科大学第三医院山西白求恩医院山西医学科学院骨科山西省太原市030000 山西医科大学基础医学研究中心山西省晋中市030600 山西医科大学基础医学院病理教研室山西省晋中市030600

背景:脊髓损伤导致的心功能不全是脊髓损伤患者死亡的重要原因,但具体机制并不清楚。因此,揭示脊髓损伤患者出现心功能不全的机制对于提高患者的生存质量和生存率有重要意义。目的:探讨木犀草素改善脊髓损伤大鼠血清诱导心肌细胞死亡的... 详细信息

背景:脊髓损伤导致的心功能不全是脊髓损伤患者死亡的重要原因,但具体机制并不清楚。因此,揭示脊髓损伤患者出现心功能不全的机制对于提高患者的生存质量和生存率有重要意义。目的:探讨木犀草素改善脊髓损伤大鼠血清诱导心肌细胞死亡的作用机制。方法:使用Allen’s冲击仪损伤雄性SD大鼠脊椎T9-T11,进行脊髓损伤造模,设置假手术组作为对照,取各组大鼠血清。将H9c2细胞分为空白对照组、假手术大鼠血清组、脊髓损伤大鼠血清组以及木犀草素预处理组,空白对照组为普通培养基培养,假手术大鼠血清组使用含体积分数10%假手术大鼠血清的培养基培养,脊髓损伤大鼠血清组使用含体积分数10%脊髓损伤大鼠血清的培养基培养,木犀草素预处理组预先使用含有终浓度为20μmol/L木犀草素的培养基培养心肌细胞4 h,之后更换含体积分数10%脊髓损伤大鼠血清的培养基培养,培养24 h后使用CCK-8法检测各组H9c2心肌细胞的存活率,采用Western blot检测各组H9c2心肌细胞自噬相关蛋白LC3及p62的蛋白表达。结果与结论:与空白对照组相比,假手术大鼠血清组细胞存活率无明显改变(P>0.05);与假手术大鼠血清组相比,脊髓损伤大鼠血清组细胞存活率显著降低(P<0.01),LC3蛋白表达显著降低(P<0.05),p62蛋白表达显著升高(P<0.05);与脊髓损伤大鼠血清组相比,木犀草素预处理组细胞存活率明显回升(P<0.0001),LC3蛋白表达显著升高(P<0.05),p62蛋白表达显著降低(P<0.05)。结果表明:木犀草素可能通过促进自噬进而改善脊髓损伤大鼠血清诱导的心肌细胞死亡。

关键词：脊髓损伤血清 H9c2细胞自噬木犀草素心功能不全

数字新质生产力赋能城乡公共医疗服务均等化:理论逻辑、现实问题和实践路径

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河南社会科学 2025年第1期33卷 82-90页

作者：魏成龙袁明硕北京师范大学政府管理学院北京100080

贯彻落实共同富裕的基本目标,需要解决我国城乡公共医疗卫生体系不平衡、不充分的现实问题,建设更加公平、可持续、高质效的公共医疗服务保障体系。在数字时代背景下,如何运用数字新质生产力赋能城乡公共医疗服务实现上述目标,急需理论... 详细信息

贯彻落实共同富裕的基本目标,需要解决我国城乡公共医疗卫生体系不平衡、不充分的现实问题,建设更加公平、可持续、高质效的公共医疗服务保障体系。在数字时代背景下,如何运用数字新质生产力赋能城乡公共医疗服务实现上述目标,急需理论探索和实践响应。数字新质生产力能够利用技术嵌入建立底层支撑实现要素创新,通过范式搭建促进管理优化实现质效提升,推动生态构建促进创新链、产业链、人才链三链交互实现数字公共医疗服务和农村经济协同发展,从而持续赋能城乡公共医疗服务均等化。基于创新需求驱动力不足的技术突破瓶颈、数字脱钩与数字鸿沟的管理优化堵点、两大领域三链脱嵌的模式升级困境,需要准确把握数字新质生产力赋能城乡公共医疗服务均等化的实践路径,以制度激励与治理并举加快数字医疗和数字农业双领域产学研政协同,以补短固强与兼顾少数促进多维度数字应用水平提升,以共同契约与模式推广打造多层次医疗供给体系,实现城乡公共医疗服务的机会均等、水平均等和结果均等。

关键词：数字新质生产力城乡公共医疗服务均等化理论逻辑

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认知症污名的研究新进展

中国全科医学 2025年第5期28卷 631-638页

作者：袁易卿陈虹霖复旦大学社会发展与公共政策学院上海市200433 东芬兰大学社会科学院库奥皮奥70211

认知障碍又称认知症。随着人口老龄化进程的加快,受认知症和阿尔茨海默病影响的人群在不断增多。有关认知症的污名在国际社会被公认为普遍存在,但相关的研究却十分有限。本文通过梳理既往有关认知症污名的研究成果,发现有关认知症污名... 详细信息

认知障碍又称认知症。随着人口老龄化进程的加快,受认知症和阿尔茨海默病影响的人群在不断增多。有关认知症的污名在国际社会被公认为普遍存在,但相关的研究却十分有限。本文通过梳理既往有关认知症污名的研究成果,发现有关认知症污名的定义和测量方式有待统一,有关经济欠发达地区的研究十分欠缺,能够进行因果推断的证据缺乏,干预研究的数量和质量均有很大的提升空间。对于认知症污名的研究,为打破传统污名研究领域中二元主体视角提供了难得的契机。同时,对认知症污名形成机制的讨论,也可以深化学界对标签理论和归因理论的探讨。

关键词：认知障碍认知阿尔茨海默病痴呆污名综述

Molecule‑Level Multiscale Design of Nonflammable Gel Polymer Electrolyte to Build Stable SEI/CEI for Lithium Metal Battery

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Nano-Micro Letters 2025年第1期17卷 404-423页

作者： Qiqi Sun Zelong Gong Tao Zhang Jiafeng Li Xianli Zhu Ruixiao Zhu Lingxu Wang Leyuan Ma Xuehui Li Miaofa yuan Zhiwei Zhang Luyuan Zhang Zhao Qian Longwei Yin Rajeev Ahuja Chengxiang Wang Key Laboratory for Liquid‑Solid Structural Evolution and Processing of Materials(Ministry of Education) School of Materials Science and EngineeringShandong UniversityJinan 250061People’s Republic of China Condensed Matter Theory Department of Physics and AstronomyUppsala UniversityUppsala 75120Sweden

The risk of flammability is an unavoidable issue for gel polymer electrolytes(GPEs).Usually,flameretardant solvents are necessary to be used,but most of them would react with anode/cathode easily and cause serious interfacial instability,which is a big challenge for design and application of nonflammable ***,a nonflammable GPE(SGPE)is developed by in situ polymerizing trifluoroethyl methacrylate(TFMA)monomers with flame-retardant triethyl phosphate(TEP)solvents and LiTFSI–LiDFOB dual lithium *** is strongly anchored to PTFMA matrix via polarity interaction between-P=O and-CH_(2)CF_(3).It reduces free TEP molecules,which obviously mitigates interfacial reactions,and enhances flame-retardant performance of TEP *** TEP molecules are also inhibited in solvation of Li^(+),leading to anion-dominated solvation sheath,which creates inorganic-rich solid electrolyte interface/cathode electrolyte interface *** coordination structure changes Li^(+)transport from sluggish vehicular to fast structural transport,raising ionic conductivity to 1.03 mS cm^(-1) and transfer number to 0.41 at 30℃.The Li|SGPE|Li cell presents highly reversible Li stripping/plating performance for over 1000 h at 0.1 mA cm^(−2),and 4.2 V LiCoO_(2)|SGPE|Li battery delivers high average specific capacity>120 mAh g^(−1) over 200 *** study paves a new way to make nonflammable GPE that is compatible with Li metal anode.

关键词： Anchoring effect Nonflammable gel electrolyte In situ cross-linked Electrode-electrolyte interface Li metal battery

Leaching of vanadium,sodium,and silicon from molten V?Ti-bearing slag obtained from low-grade vanadium-bearing titanomagnetite

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International Journal of Minerals,Metallurgy and Materials 2016年第8期23卷 898-905页

作者： yuan-yuan Zhu University of Chinese Academy of Sciences Beijing 100049China National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China Key Laboratory of Green Process and Engineering Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China

The water leaching process of vanadium, sodium, and silicon from molten vanadium-titanium-bearing（V-Ti-bearing） slag obtained from low-grade vanadium-bearing titanomagnetite was investigated systematically. The results show that calcium titanate, sodium aluminosilicate, sodium oxide, silicon dioxide and sodium vanadate are the major components of the molten V-Ti-bearing slag. The experimental results indicate that the liquid-solid（L/S） mass ratio significantly affects the leaching process because of the respective solubilities and diffusion rates of the components. A total of 83.8% of vanadium, 72.8% of sodium, and 16.1% of silicon can be leached out via a triple counter-current leaching process under the optimal conditions of a particle size below 0.074 mm, a temperature of 90°C, a leaching time of 20 min, an L/S mass ratio of 4：1, and a stirring speed of 300 r/min. The kinetics of vanadium leaching is well described by an internal diffusion-controlled model and the apparent activation energy is 11.1 kJ/mol. The leaching mechanism of vanadium was also analyzed.

关键词： titanomagnetite vanadium metallurgy leaching kinetics sodium silicon leaching rate

Condensed Galerkin element of degree m for first-order initial-value problem with O(h^(2m+2))super-convergent nodal solutions

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Applied Mathematics and Mechanics(English Edition) 2022年第4期43卷 603-614页

作者： Si yuan Quan yuan Department of Civil Engineering Key Laboratory of Civil Engineering Safety and Durability of China Education MinistryTsinghua UniversityBeijing 100084China

A new type of Galerkin finite element for first-order initial-value problems(IVPs)is *** the trial and test functions employ the same m-degreed *** adjoint equation is used to eliminate one degree of freedom(DOF)from the test function,and then the so-called condensed test function and its consequent condensed Galerkin element are *** is mathematically proved and numerically verified that the condensed element produces the super-convergent nodal solutions of O(h^(2m+2)),which is equivalent to the order of accuracy by the conventional element of degree m+*** related properties are addressed,and typical numerical examples of both linear and nonlinear IVPs of both a single equation and a system of equations are presented to show the validity and effectiveness of the proposed element.

关键词： Galerkin method finite element method(FEM) condensed element superconvergence adjoint operator initial-value problem(IVP)

Two performance enhanced control of flexible-link manipulator with system uncertainty and disturbances

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Science China(Information Sciences) 2017年第5期60卷 25-35页

作者： Bin XU yuan yuan School of Automation Northwestern Polytechnical University School of Automation Science and Electrical Engineering Beihang University

Precision control of flexible-link manipulator for space operation is challenging due to the dynamics coupling and system uncertainty. In this paper, to deal with system uncertainty and time-varying disturbance,two performance enhanced controller designs, named Composite Learning Control and Disturbance Observer Based Control are presented respectively. To overcome the nonminimum phase, using output redefinition, the dynamics is transformed to two subsystems: internal system and input-output system. For the internal dynamics,the PD(proportion differentiation) control is used with pole assignment. For the input-output subsystem,considering the unknown dynamics, the composite learning control is designed using neural modeling error while in case of disturbance, the disturbance observer based design is proposed. The stability analysis of the closed-loop system is presented via Lyapunov approach. Simulation of 2-degrees of freedom(DOF) flexible-link manipulator is conducted and the results show that the proposed methods can enhance the tracking performance.

关键词： flexible-link manipulator composite learning control disturbance observer output redefinition system uncertainty

Visualized Bond Scission in Mechanically Activated Polymers

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Chinese Journal of Polymer Science 2017年第11期35卷 1315-1315,1316-1327页

作者： yuan yuan 陈于蓝 Department of Chemistry Tianjin Key Laboratory of Molecular Optoelectronic Sciences Tianjin University and Collaborative Innovation Center of Chemical Science and Engineering

Visualization and quantitative evaluation of covalent bond scission in polymeric materials are critical in understanding their failure mechanisms and improving the toughness and reliability of the materials. Mechano-responsive polymers with the ability of molecular-level transduction of force into chromism and luminescence have evoked major interest and experienced significant progress. In the current review, we highlight the recent achievements in covalent mechanochromic and mechanoluminescent polymers, leading to a bridge between macroscopic mechanical properties and microscopic bond scission events. After a general introduction concerning polymer mechanochemistry, various examples that illustrate the strategies of design and incorporation of functional and weak covalent bonds in polymers were presented, the mechanisms underlying the optical phenomenon were introduced and their potential applications as stress sensors were discussed. This review concludes with a comment on the opportunities and challenges of the field.

关键词： Mechanochemistry Mechanochromic polymer Mechanoluminescent polymer Stress sensor