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国土空间规划背景下黄河流域水生态空间格局演变特征及其影响因素

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水土保持研究 2025年第2期32卷 178-190页

作者：薄立明赵浪尹力张翔魏伟武汉大学中国发展战略与规划研究院武汉430072 武汉大学城市设计学院武汉430072 中国地质大学(武汉)国家地理信息系统工程技术研究中心武汉430078 湖北省人居环境工程技术研究中心武汉430072

[目的]科学认知黄河流域上、中、下游水生态空间格局演化特征及影响因素,促进水资源用途管制客体向国土空间规划体系治理系统的融入,推动黄河流域生态保护和高质量发展。[方法]采用空间转移矩阵、最优地理探测器等量化模型分析黄河流域... 详细信息

[目的]科学认知黄河流域上、中、下游水生态空间格局演化特征及影响因素,促进水资源用途管制客体向国土空间规划体系治理系统的融入,推动黄河流域生态保护和高质量发展。[方法]采用空间转移矩阵、最优地理探测器等量化模型分析黄河流域上、中、下游水生态空间格局演变的区域差异,剖析了水生态空间格局演变路径并揭示其内在影响因素。[结果](1)黄河流域水生态空间规模为2.76万km^(2),仅占流域国土总面积的2.28%,上、中、下游水生态空间规模占比为22∶2∶3,研究期内规模性扩张了4 989.90 km^(2),上游地区增长规模最大,下游地区增长幅度最剧烈。(2)上游地区水生态空间主要与其他生态空间发生交叉转换,引起水生态空间大规模扩张,其次是与农业空间交互转换造成水生态空间小规模流失;中游地区水生态空间主要与农业空间发生交叉转换,其次是其他生态空间,引起水生态空间小规模扩张;下游地区农业空间向水生态空间的转换引起水生态空间大规模扩张的同时水生态空间也规模性转换为城镇空间。(3)上游地区水生态空间规模性扩张核心影响因素是水资源“液态化”的水文循环过程,流失则是主要由第一、三产业发展诉求驱动;中游地区水生态空间格局演变整体表现为政府财政所主导的适配地区自然地理条件、社会经济发展的水资源调配过程;下游地区则是水生态空间伴随城镇化进程在农业地区和城镇地区的转移。[结论]黄河流域上、中、下游水生态空间格局演变特征、路径和影响因素差异显著,需要根据各区域水资源保护利用的发展定位,建立起共同治理、协同发展的流域协作体系。

关键词：水生态空间国土空间规划用途管制时空格局黄河流域

Generalized Covariant Derivative with Respect to Time in Flat Space(Ⅱ):Lagrangian Description

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Acta Mechanica Solida Sinica 2016年第4期29卷 359-370页

作者： Yajun yin Department of Engineering Mechanics School of Aerospace Engineering Tsinghua University

The previous paper reported a new derivative in the Eulerian description in flat space—the generalized covariant derivative of generalized Eulerian component with respect to time. This paper extends the thought from the Eulerian description to the Lagrangian description:on the basis of the postulate of covariant form invariability in time field, we define a new derivative in the Lagrangian description in flat space—the generalized covariant derivative of generalized Lagrangian component with respect to time. Besides, the covariant differential transformation group is set up. The covariant form invariability of Lagrangian space-time is ascertained.

关键词： Lagrangian description the postulate of covariant form invariability generalized Lagrangian component generalized covariant derivative with respect to time covariant differential transformation group

基于简易冲击分解模型的爆轰驱动硅橡胶数值模拟及实验解读

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爆炸与冲击 2025年第1期45卷 123-132页

作者：刘军殷建伟张凤国北京应用物理与计算数学研究所北京100094

为了反映爆轰驱动下硅橡胶发生冲击分解反应的物理过程,提出了一种简易的硅橡胶冲击分解模型。基于该模型,对爆轰驱动含硅橡胶夹层钢板实验进行了模拟,并分析解读了钢板的自由面速度。结果表明,实验中硅橡胶发生了冲击分解反应,导致钢... 详细信息

为了反映爆轰驱动下硅橡胶发生冲击分解反应的物理过程,提出了一种简易的硅橡胶冲击分解模型。基于该模型,对爆轰驱动含硅橡胶夹层钢板实验进行了模拟,并分析解读了钢板的自由面速度。结果表明,实验中硅橡胶发生了冲击分解反应,导致钢板的自由面速度曲线出现了首次起跳中间速度平台及首次起跳速度峰值降低的现象。受硅橡胶冲击分解影响,首次入射波压力将在临界冲击分解压力附近弛豫一段时间,再继续升高至最高压力。该压力波作用于钢板的自由面后,出现了自由面速度在中间速度平台停留一段时间,之后继续升高至速度峰值的现象。硅橡胶冲击分解后的气相物质可压缩性较高,首次加载波内较多的能量被用于压缩气体做功,导致首次波传播至自由面时能量衰减,峰值压力降低,首次起跳速度峰值降低。

关键词：硅橡胶爆轰驱动冲击分解分解压力

Large deflection of clamped circular plate and accuracy of its approximate analytical solutions

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Science China(Physics,Mechanics & Astronomy) 2016年第2期59卷 67-77页

作者： yin Zhang State Key Laboratory of Nonlinear Mechanics(LNM) Institute of Mechanics Chinese Academy of Sciences

A different set of governing equations on the large deflection of plates are derived by the principle of virtual work(PVW), which also leads to a different set of boundary conditions. Boundary conditions play an important role in determining the computation accuracy of the large deflection of plates. Our boundary conditions are shown to be more appropriate by analyzing their difference with the previous ones. The accuracy of approximate analytical solutions is important to the bulge/blister tests and the application of various sensors with the plate structure. Different approximate analytical solutions are presented and their accuracies are evaluated by comparing them with the numerical results. The error sources are also analyzed. A new approximate analytical solution is proposed and shown to have a better approximation. The approximate analytical solution offers a much simpler and more direct framework to study the plate-membrane transition behavior of deflection as compared with the previous approaches of complex numerical integration.

关键词： approximate analytical solutions large deflection plate membrane bulge and blister tests

The Particle Time Derivative of the Characteristic Geometric Quantities on Soft Curved Surface in Lagrangian Description

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Acta Mechanica Solida Sinica 2018年第6期31卷 683-697页

作者： Yajun yin Department of Engineering Mechanics School of Aerospace EngineeringTsinghua UniversityBeijing 100084China

This paper studies the particle time derivatives of the characteristic geometric quantities on soft curved surfaces in Lagrangian *** the basis of differential geometry, the calculation formulas for the particle time derivatives of the base vectors,metric tensor, Christoffel symbol,unit normal vector,curvature tensor and scalar curvatures on soft curved surface are *** limitations of particle time derivatives,*** non-covariance,are pointed *** research paves the way for studying particle time derivative of any tensor field on soft curved surface.

关键词： Soft curved surfaces Lagrangian description Characteristic geometric quantities Particle time derivative

Generalized Covariant Derivative with Respect to Time in Flat Space(Ⅰ):Eulerian Description

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Acta Mechanica Solida Sinica 2016年第4期29卷 345-358页

作者： Yajun yin Department of Engineering Mechanics School of Aerospace EngineeringTsinghua University

This paper reports a new derivative in the Eulerian description in flat space-the generalized covariant derivative with respect to time. The following contents are included:(a) the restricted covariant derivative with respect to time for Eulerian component is defined;(b) the postulate of the covariant form invariability in time field is set up;(c) the generalized covariant derivative with respect to time for generalized Eulerian component is defined;(d) the algebraic structure of the generalized covariant derivative with respect to time is made clear;(e) the covariant differential transformation group in time filed is derived. These progresses reveal the covariant form invariability of Eulerian space and time.

关键词： Eulerian description covariant form invariability generalized Eulerian component generalized covariant derivative with respect to time covariant differential transformation group

Generalized covariant differentiation and axiom-based tensor analysis

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Applied Mathematics and Mechanics(English Edition) 2016年第3期37卷 379-394页

作者： Yajun yin Department of Engineering Mechanics School of Aerospace EngineeringTsinghua University

This paper reports the new progresses in the axiomatization of tensor anal- ysis, including the thought of axiomatization, the concept of generalized components, the axiom of covariant form invariability, the axiomatized definition, the algebraic structure, the transformation group, and the simple calculation of generalized covariant differentia- tions. These progresses strengthen the tendency of the axiomatization of tensor analysis.

关键词： tensor analysis axiom of covariant form invariability generalized compo-nent generalized covariant differentiation covariant differential transformation group

Gold nanoparticle-directed autophagy intervention for antitumor immunotherapy via inhibiting tumor-associated macrophage M2 polarization

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Acta Pharmaceutica Sinica B 2022年第7期12卷 3124-3138页

作者： Siyue Zhang Fangyuan Xie Kaichun Li He Zhang You yin Yuan Yu guangzhao Lu Shihao Zhang Yan Wei Ke Xu Yan Wu Hong Jin Lan Xiao Leilei Bao Can Xu Yulin Li ying Lu Jie Gao Department of Pharmacy Naval Medical UniversityShanghai 200433China Changhai Clinical Research Unit Shanghai Changhai HospitalNaval Medical UniversityShanghai 200433China Institute of Translational Medicine Shanghai UniversityShanghai 200444China Department of Pharmacy Shanghai Eastern Hepatobiliary Surgery HospitalNaval Medical UniversityShanghai 200433China Department of Oncology Shanghai Fourth People’s HospitalSchool of MedicineTongji UniversityShanghai 200434China Unit for Drug and Instrument Supervision and Inspection of Wuxi Joint Logistic Support Center Nanjing 210000China Key Laboratory for Ultrafine Materials of Ministry of Education Engineering Research Center for Biomedical Materials of Ministry of EducationSchool of Materials Science and EngineeringEast China University of Science and TechnologyShanghai 200237China Department of Gastroenterology Shanghai Changhai HospitalNaval Medical UniversityShanghai 200433China Department of Neurology Changzheng HospitalNaval Medical UniversityShanghai 200003China Department of Biomaterial College of Life SciencesMudanjiang Medical UniversityMudanjiang 157011China Department of Laboratory Medicine Hongqi HospitalMudanjiang Medical CollegeMudanjiang 157011China Centre for Biomedical Technologies Queensland University of TechnologyBrisbane QLD 4000Australia mWenzhou Institute of Shanghai UniversityWenzhou 325000China

Tumor-associated macrophages(TAMs),one of the dominating constituents of tumor microenvironment,are important contributors to cancer progression and treatment ***,regulation of TAMs polarization from M2 phenotype towards M1 phenotype has emerged as a new strategy for tumor ***,we successfully initiated antitumor immunotherapy by inhibiting TAMs M2 polarization via autophagy intervention with polyethylene glycol-conjugated gold nanoparticles(PEG-Au NPs).PEG-Au NPs suppressed TAMs M2 polarization in both in vitro and in vivo models,elicited antitumor immunotherapy and inhibited subcutaneous tumor growth in *** demonstrated by the m RFP-GFP-LC3 assay and analyzing the autophagy-related proteins(LC3,beclin1 and P62),PEGAu NPs induced autophagic flux inhibition in TAMs,which is attributed to the PEG-Au NPs induced lysosome alkalization and membrane ***,TAMs were prone to polarize towards M2phenotype following autophagy activation,whereas inhibition of autophagic flux could reduce the M2polarization of *** results revealed a mechanism underlying PEG-Au NPs induced antitumor immunotherapy,where PEG-Au NPs reduce TAMs M2 polarization via induction of lysosome dysfunction and autophagic flux *** study elucidated the biological effects of nanomaterials on TAMs polarization and provided insight into harnessing the intrinsic immunomodulation capacity of nanomaterials for effective cancer treatment.

关键词： Macrophage polarization Tumor-associated macrophages Nanomaterials Autophagy flux Lysosomal damage Gold nanoparticles M2 macrophage Cancer therapy

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农业拖拉机尾灯多色注塑模具设计

农机化研究 2025年第1期47卷 239-242,247页

作者：尹小定赵会娟江西机电职业技术学院机械工程学院南昌330013 济源职业技术学院机电工程系河南济源454650

以农业拖拉机尾灯为研究对象,分析了尾灯的内部结构和工艺性,并针对双色模具的特殊性,分析了模具成型方案和设计流程,基于AutoCAD和CAE软件完成了尾灯双色塑件模具的设计。开模试验表明:该产品符合设计需求,整个产品结构稳定,透明度好,... 详细信息

以农业拖拉机尾灯为研究对象,分析了尾灯的内部结构和工艺性,并针对双色模具的特殊性,分析了模具成型方案和设计流程,基于AutoCAD和CAE软件完成了尾灯双色塑件模具的设计。开模试验表明:该产品符合设计需求,整个产品结构稳定,透明度好,设计的模具结构合理、工艺流程可靠,能够满足实际的生产应用,工程应用价值较高。

关键词：农业拖拉机尾灯 CAD CAE 双色塑件模具

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