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地区新质生产力对企业全要素生产率的影响与机制

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中国流通经济 2025年第1期39卷 100-114页

作者：张树山刘赵宁东北师范大学经济与管理学院吉林长春130117

发展新质生产力是推动经济高质量发展的内在要求和重要着力点。从微观视角出发,考察具有显著差异化特征的地区新质生产力对企业全要素生产率的影响效应及其内在机制,不仅能够为加速形成新质生产力提供精准的政策指引,还能够为经济运行... 详细信息

发展新质生产力是推动经济高质量发展的内在要求和重要着力点。从微观视角出发,考察具有显著差异化特征的地区新质生产力对企业全要素生产率的影响效应及其内在机制,不仅能够为加速形成新质生产力提供精准的政策指引,还能够为经济运行的关键微观基础提供有效改善生产效率的战略指导。基于2012—2022年我国30个省份(未含港澳台藏)和沪深A股上市公司数据,在通过熵值法测算地区新质生产力发展水平的基础上,利用文本分析法、固定效应模型,深入探究地区新质生产力对企业全要素生产率的影响及其机制。研究发现,地区新质生产力能显著提升企业全要素生产率。从机制检验结果来看,地区新质生产力能够通过赋能企业数字技术创新突破、数字技术应用成效以及内外部交易成本降低,进而提高企业全要素生产率,且公司内部治理与市场公平竞争环境的强化均能增强地区新质生产力对企业生产率的提升效应。异质性检验结果表明,在非国有企业、制造业以及胡焕庸线以东地区,地区新质生产力对企业全要素生产率提升作用更加明显。为此,应在因地制宜的原则下培育和发展新质生产力,统筹推进新型基础设施建设,重视并激发数据要素潜能,促进传统产业和新兴产业协调发展;重视企业治理效能提升,优化信息披露机制,强化披露质量,同时鼓励金融机构将公司治理水平纳入信用评估体系,切实提升公司治理能力;努力营造公平竞争的市场环境,严格落实公平竞争审查,维护良好市场秩序与健康竞争生态,以期助力新质生产力的重大战略意义实现。

关键词：新质生产力全要素生产率市场公平竞争公司治理

Selective G6PDH inactivation for Helicobacter pylori eradication with transformed polysulfide

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Science China Life Sciences 2025年

作者： Xiaonan Wang ning Zhou Xuejiao J.Gao Zijing Zhu Minmin Sun Qian Wang Haolin Cao Xuetong Wu Caiyu Zhou Qingkang Zheng Ye Yuan Yuan Liu Lei Chen Jing Jiang Pengcheng Bu Lizeng Gao CAS Engineering Laboratory for Nanozyme Key Laboratory of Biomacromolecules Institute of Biophysics Chinese Academy of Sciences School of Life Sciences University of Chinese Academy of Sciences College of Chemistry and Chemical Engineering Jiangxi Normal University Key Laboratory of Epigenetic Regulation and Intervention Institute of Biophysics Chinese Academy of Sciences Nanozyme Laboratory in Zhongyuan School of Basic Medical Sciences Zhengzhou University Nanozyme Laboratory in Zhongyuan Henan Academy of Innovations in Medical Science

Alternative treatment for the highly prevalent Helicobacter pylori infection is imperative due to rising antibiotic resistance. We unexpectedly discovered that the anti-H. pylori component in garlic is hydrogen polysulfide（H2S_n, n≥2）, not organic polysulfides. Studies on the mechanism of action（MoA） show that H2S_nspecifically inactivates H. pylori glucose-6-phosphate dehydrogenase（G6PDH） by interfering with electron transfer from glucose-6-phosphate（G6P） to nicotinamide adenine dinucleotide phosphate（NADP+）. However, low H2S_nyield makes garlic derivatives hard to be a reliable donor of H2S_nto treat H. pylori infection. To address this challenge, we established a polysulfide transformation process from garlic organosulfur compounds into Fe3S4that generates H2S_nwith a 25–58 times increase in *** chitosan encapsulation, we designed a gastric-adaptive H2S_nmicroreactor（GAPSR） that eradicates H. pylori with 250 times higher efficiency under gastric conditions. A single GAPSR achieves more rapid H. pylori eradication than combined antibiotics therapy without disturbing the gut microbiota. These findings indicate a distinct MoA transformation mediated by polysulfide as an alternative candidate to treat H. pylori infection.

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SUPERCONVERGENCE AND A POSTERIORI ERROR ESTIMATES FOR BOUNDARY CONTROL GOVERNED BY STOKES EQUATIONS

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Journal of Computational Mathematics 2006年第3期24卷 343-356页

作者： Hui-po Liu ning-ning Yan Institute of Systems Science Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100080 China

In this paper, the superconvergence results are derived for a class of boundary control problems governed by Stokes equations. We derive superconvergence results for both the control and the state approximation. Base ... 详细信息

关键词： Boundary control Finite element method Superconvergence A posteriori error estimates.

考虑台风效应的金属屋面系统全寿命期疲劳损伤估计

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工程力学 2025年第1期42卷 189-198页

作者：宣颖张乐乐谢壮宁华南理工大学亚热带建筑科学国家重点实验室广州510640 中国建筑第二工程局有限公司华南公司深圳518048

评估金属屋面设计使用寿命年限内的累积损伤程度是抗风设计的重要环节，该文提出一种用于台风多发区域金属屋面系统全寿命期风致疲劳损伤的估计方法，该方法结合风洞测压试验数据和基于台风Monte Carlo模拟所得风速风向分布模型，采用... 详细信息

评估金属屋面设计使用寿命年限内的累积损伤程度是抗风设计的重要环节，该文提出一种用于台风多发区域金属屋面系统全寿命期风致疲劳损伤的估计方法，该方法结合风洞测压试验数据和基于台风Monte Carlo模拟所得风速风向分布模型，采用有限元数值模拟方法进行荷载应力分析，提取金属屋面板块疲劳热点处荷载应力关系，从而获得应力时程数据，通过雨流计数法统计应力循环数，并根据Goodman应力修正法则和Miner疲劳线性累积损伤理论，计算得到金属屋面系统在全寿命期的疲劳累积损伤情况;利用台风等效序列进行加载，以动态物理压力箱试验验证数值模拟方法有效性为基础，将该文方法应用于位于东南沿海的某大跨度圆柱形金属屋面的疲劳累积损伤估计。结果显示：金属屋面全寿命期风致疲劳损伤不仅与风压分布存在一定相关性，也与建筑物所在地区的极值风速分布和主导风向存在相关性，评估全寿命期风致疲劳损伤应结合风洞测压试验结果和建筑物所在地风速风向分布模型进行综合分析;对于更易出现疲劳破坏的屋面角区和边缘部位的高负压区域，量化分析局部加密角区和边缘部位檩距对风致疲劳损伤的影响。

关键词：金属屋面板有限元分析风洞试验风致疲劳损伤台风模型

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波箔型空气箔片轴承疲劳寿命的计算方法

轴承 2025年第1期 23-30页

作者：宁培栋李双敏安琦华东理工大学机械与动力工程学院上海200237

以波箔型空气箔片轴承为例,构建了波箔变形的力学模型,并结合可压缩气体雷诺方程,建立求解气膜压力的流固耦合算法。在此基础上对顶箔和波箔进行应力分析,运用线性疲劳损伤累计理论构建了顶箔和波箔的疲劳寿命计算方法,结合具体算例进... 详细信息

以波箔型空气箔片轴承为例,构建了波箔变形的力学模型,并结合可压缩气体雷诺方程,建立求解气膜压力的流固耦合算法。在此基础上对顶箔和波箔进行应力分析,运用线性疲劳损伤累计理论构建了顶箔和波箔的疲劳寿命计算方法,结合具体算例进行数值研究。结果表明:轴承正常运转时,波箔的疲劳损伤率远大于顶箔的疲劳损伤率;在忽略启停阶段对顶箔摩擦磨损的前提下,轴承的疲劳寿命主要由波箔决定;波箔的疲劳寿命随波拱圆弧角度、波拱圆弧半径和波距的增大而减小,随半径间隙和波箔厚度的增大而增大。

关键词：滑动轴承箔片轴承力学模型数值计算疲劳寿命最大应力

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Delaunay graph-based moving mesh method with damping functions

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Chinese Journal of Aeronautics 2018年第11期31卷 2093-2103页

作者： Yibin WANG ning QIN ning ZHAO College of Aerospace Engineering Nanjing University of Aeronautics and Astronautics Department of Mechanical Engineering The University of Sheffield

The fluid–structure interaction and aerodynamic shape optimization usually involve the moving or deforming boundaries, thus the dynamic mesh techniques are the key techniques to cope with such deformation. A novel dynamic mesh method was developed based on the Delaunay graph in this paper. According to the Delaunay graph, the mesh points were divided into groups. In each group, a factor ranging from 0 to 1 was calculated based on the area/volume ratio. By introducing a proper function for this factor, this method can control the mesh quality with high efficiency. Several test cases were compared with other dynamic mesh methods regarding mesh quality and CPU time, such as radial basis function method and Delaunay graph mapping method.

关键词： Delaunay graph mapping Dynamic mesh Grid deformation Mesh Moving mesh

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北师大版初中数学新教材的特色及变化分析

教学与管理 2025年第1期 44-48页

作者：常海斌宁依敏首都师范大学教育学院北京100048 华东师范大学数学科学学院上海200241

深刻理解和准确解读教材是有效使用教材的前提。北师大版初中数学新教材遵循“教育本位”的教材编写理念,在章首语、栏目设置、问题解决、习题设计和素材选取上各具特色;教材整体采用跨领域混编、螺旋式上升和小结整合式的编写模式,着... 详细信息

深刻理解和准确解读教材是有效使用教材的前提。北师大版初中数学新教材遵循“教育本位”的教材编写理念,在章首语、栏目设置、问题解决、习题设计和素材选取上各具特色;教材整体采用跨领域混编、螺旋式上升和小结整合式的编写模式,着重凸显课程内容的结构化和认知过程的进阶性;四个学习领域以“研究对象”的形式进行内容整合,具有重视代数推理、重构统计量的组合形式以及对综合与实践领域进行主题迭代和核心创变等变化。

关键词：初中数学新教材教材编写特色北师大版教材新教材变化分析

杜诗叙事画论析--以成都杜甫草堂博物馆馆藏绘画为中心

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重庆文理学院学报（社会科学版） 2025年第1期44卷 127-140页

作者：陈宁房锐四川师范大学文学院四川成都610066 成都杜甫草堂博物馆四川成都610072

关于叙事画的概念,中国和西方存在着一定的差异,但在叙事手法、教化功能和图文关系等方面也存在一定的共识。文章在明确叙事画的概念、范畴和功能之后,通过对明清至近现代繁盛起来的杜诗叙事画的文本来源、画家群体及创作原因、选材与... 详细信息

关于叙事画的概念,中国和西方存在着一定的差异,但在叙事手法、教化功能和图文关系等方面也存在一定的共识。文章在明确叙事画的概念、范畴和功能之后,通过对明清至近现代繁盛起来的杜诗叙事画的文本来源、画家群体及创作原因、选材与形制的关系、艺术手法的演变四个方面进行详细分析,进一步明晰杜诗叙事画的图文关系。杜诗叙事画是对文本来源为杜诗内容的艺术展示,是画家对杜甫叙事诗的接收与传播;同时,观者通过叙事性的图画溯源于杜诗,可以加深对杜诗内容及其反映的唐代社会现实的深刻理解,体味杜甫的圣者仁心,并加深对其图文关系的认知。

关键词：杜甫叙事画叙事诗图文关系

Changing structures of summertime heatwaves over China during 1961–2017

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Science China Earth Sciences 2021年第8期64卷 1242-1253页

作者： ning AN Zhiyan ZUO State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China Department of Atmospheric and Oceanic Sciences/Institute of Atmospheric Sciences Fudan UniversityShanghai 200438China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science and TechnologyNanjing 210044China

Despite the prevalence of artificial separation of daytime and nighttime hot extremes, they may actually co-occur or occur sequentially. Considering their potential lead-lag configuration, this study identified an entire heatwave period as consecutive days with either daytime or nighttime hot extremes and investigated the changes of the prevalence and sequence of daytime and nighttime hot extremes during heatwaves over China from 1961 to 2017. It was found that the majority(82%) of heatwaves were compound heatwaves that had both daytime and nighttime hot extremes exceeding the 90 th percentile-based thresholds, while only 7%(11%) were purely daytime(nighttime) heatwaves that contained only daytime(nighttime) hot extremes. During the entire periods of compound heatwaves, daytime hot extremes usually occurred one day or a few days before nighttime hot extremes, which was in accordance with the daily variations in radiation and meteorological conditions, such as the increasing surface humidity and cloud cover, and decreasing solar radiation during the entire heatwave periods. From 1961 to2017, compound heatwave numbers exhibited the sharpest increase with a statistically significant trend of 0.44 times decade-1, in contrast to an insignificant trend of 0.00 times decade-1 for purely daytime heatwaves and a significant trend of 0.09 times decade-1 for purely nighttime heatwaves. Within the compound heatwave periods, hot nights were starting earlier and ending later, and numbers of concurrent daytime-nighttime hot extremes increased significantly at 0.20 days decade-1. In particular,urban area were not only subject to increasingly more frequent and longer compound heatwaves, but also to more occurrences of concurrent daytime-nighttime hot extremes with more serious impact. This study provides instructions for researchers to customize and select appropriate heatwave indices.

关键词： Heatwaves Daytime-nighttime coupling Urbanization Meteorological conditions