Results 11 to 20 of about 13,453 (210)
Growing Demand and Uneven Supply: Eight Years of Nature Education in China 需求增长与供给不均:中国自然教育八年发展回顾
ABSTRACT This study examines the role of nature education in advancing conservation and sustainability in China between 2014 and 2023. Drawing on national survey reports and historical–comparative methods, it analyses the dynamics of public demand, institutional supply, and practitioner capacity.
Qi Yunxi, Lyu Xiang, Huang Yu
wiley +1 more source
ABSTRACT To break electromagnetic wave absorption (EMA) tech's single‐attenuation bottleneck, enhancing multi‐wave absorption synergy in composites is key for microstructure design. This study uses mesoporous hollow carbon spheres to make metal nanospheres with cobalt, iron, and nickel nanoparticles, then encapsulates them via electrospinning into a ...
Wei‐Lian Zhang +10 more
wiley +1 more source
ABSTRACT The poor Zn chemistry of Zn metal anode and sluggish reaction kinetics of cathodes at high mass loadings are two crucial issues for hindering the application of aqueous Zn‐ion batteries (AZIBs). Herein, the hierarchical porous N‐doped carbon fibers (HPNCFs) were proposed to simultaneously optimize the reversibility of Zn plating/stripping of ...
Song Yang +6 more
wiley +1 more source
ABSTRACT Porous NiTi alloys are widely used in biomedical and engineering fields. Using the PBF‐LB technique, the TPMS and Voronoi porous parts with a porosity of ∼67% and a minimum feature size of 0.15 ± 0.02 mm were fabricated. Although the bulk sample fabricated with the same parameters is defect‐free, μ‐CT reconstruction on the porous sample ...
Wen‐Hao Zeng +7 more
wiley +1 more source
基于SVM-PSO混合算法的12kV开关柜触头盒双屏蔽结构三维电场优化研究
开关柜在长期运行过程中可能会因触头盒电场集中导致放电甚至击穿事故,采用双屏蔽结构是改善开关柜触头盒内电场分布的有效方法。为此,以KYN28A-12开关柜为研究对象,提出了一种基于SVM-PSO混合算法的开关柜触头盒双屏蔽结构三维电场优化方法。首先,在Comsol Multiphysics中建立了开关柜的三维仿真模型,分析了接地屏蔽长度、高压屏蔽半径和长度对触头盒、接地屏蔽和高压屏蔽表面场强的影响规律;然后,构建了含触头盒、接地屏蔽和高压屏蔽表面场强3个优化目标的评价函数 ...
舒胜文 +5 more
doaj
Administrative Division Adjustment、Resources Allocation and Regional Economic Growth——The Case Of Chongqing Municipality [PDF]
十八大报告曾提出“优化行政层级和行政区划设置,有条件的地方可探索省直接管理县(市)改革,深化乡镇行政体制改革”的政策方针。分析行政区划调整对经济发展影响,探索行政区划调整对地方经济增长影响机制,对我国今后地方与区域经济的发展和改革方向把握上,以及检验能否通过采用行政区划调整实现推动经济发展无疑具有重要的现实意义。 在理论方面,本文引入了制度环境因素,对Solow模型进行了拓展,并假定行政区划调整是引起制度环境变化的主要因素,分析了行政区划调整行为对均衡增长路径上各经济特征的影响。 实证方面 ...
陈刚
core
制造业行业结构优化是经济实现可持续发展的重要环节。本文基于MVE原理,测算了各国的最优制造业行业结构,并在此基础上量化了各国现有制造业行业结构与最优行业结构间的距离,分析了影响...国家社会科学基金青年项目“金融生态环境与技术创新空间集聚效应的机制研究与对策建议”(15CJL052)的阶段性成果;; 中央高校基本科研业务费专项资金项目“厦门大学人文社科创新团队”(207201..
张馨月, 武力超
core +1 more source
ABSTRACT Rare earth elements (REEs) play an irreplaceable role in modern technology and industry. However, due to the highly similar physicochemical properties among REEs, their separation remains a significant challenge. Additionally, REEs often exist in low‐concentration solutions, making efficient REE recovery an urgent task.
Miao‐Miao Huang +6 more
wiley +1 more source
为了实现固态变压器绝缘性能的提升,满足其电压等级提升和紧凑型一体化设计的需求,利用遗传算法与电场仿真联合方法优化了固态变压器高压连接处绝缘结构。首先通过建立一体化固态变压器的绝缘结构模型,计算了稳态电场分布状态及局域电场集中位置,发现高频变压器与电力电子模块连接处接地截止点局域最高电场达6.97 kV/mm,高于空气击穿强度。其次设计了圆弧形模块连接绝缘结构将接地截止点埋入固体绝缘介质中,并通过遗传算法与电场仿真联合方法优化了圆弧形结构尺寸参数,使得连接处最高电场转移至固体绝缘介质内部 ...
袁妮, 吴俊丽, 冷兆云
doaj
The Analysis of Industrial Linkages and Business Cycle Synchronization:Between China,Japan and Korea [PDF]
在经济全球化不断发展的宏观背景下,各个国家之间的经济关系越加紧密,尤其是大国之间的经济波动动辄关乎到世界经济的发展,因此对于国家之间的经济周期协动性研究也就有了更为重要的现实意义。过去对于该课题的研究大多将目光集中于经济周期协动性在国家之间的传导机制与影响因素上,目前已经得到了很多的理论与实证结果。为了更进一步的将经济周期协动性与现实中的问题联系起来,本文创新性的从产业关联分析角度出发,在国家层面的系统性指标基础上更进一步,从具体的产业层面去寻找影响经济周期协动性的相关因素 ...
张霖
core

