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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
Integrative Conservation, Volume 5, Issue 1, Page 46-58, March 2026.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
Behavior of a Flexspline in Harmonic Drive [PDF]
, 1900 谐波齿轮传动是利用柔性工作构件的弹性变形波进行运动或者动力传递的一种新型传动方式，因其具有体积小、重量轻、精度高、单级传动比大、承载能力高等诸多优点，在航空航天、机器人、数控机床等领域得到了广泛的应用。柔轮作为谐波齿轮传动的关键构件很大程度上影响了谐波齿轮传动的承载能力、使用寿命等。柔轮为弹性薄壁件，在交变载荷作用下易导致齿面磨损和疲劳断裂。柔轮强度、变形与应力分析对谐波齿轮传动过程中的疲劳断裂评估及传动性能研究具有重要的意义。 本文首先根据已知参数、实际工况和谐波齿轮传动啮合参数选取原则 ...
刘淳剑
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Rare Metals, Volume 45, Issue 3, March 2026.ABSTRACT Low conductivity, slow ion‐diffusion, and limited reactive sites are common problems in electrocatalysts and electrode materials. In this study, a complex NiTe–CoTe heterojunction with abundant Te vacancies embedded in N, P, and F co‐doped hollow carbon nanorods (NiTe1−x–CoTe1−x/NPFC) was fabricated via a simple ionic liquid‐assisted ...
Mingjie Yi +7 more
wiley +1 more source
Research on Structural Design and Mechanical Behavior of Double Arc Tooth Profile Harmonic Drive [PDF]
, 2015 谐波齿轮减速器是一种传动精度高、减速比大并能够在密闭空间传动的齿轮传动机构，应用领域广泛，尤其在航空航天领域有不可替代的优势。常用的渐开线齿廓齿根处会出现应力集中以及齿顶产生尖点啮合现象，影响其承载性能和啮合质量。双圆弧齿形谐波齿轮以其良好的承载能力与啮合性能逐渐成为研究热点，本文根据谐波齿轮设计理论设计了双圆弧谐波齿轮装置，并对其结构性能、接触特性以及动力学等方面的分析，探索相关规律，为后续在结构优化、增强啮合性能提供了一定的理论依据。 论文主要包括以下几方面内容： 1 ...
王萌萌
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Latin American Policy, Volume 17, Issue 1, March 2026.ABSTRACT Tourism and International Relations, as interdisciplinary fields, encompass diverse knowledge, making them complex subjects. This article explores how official international relations bodies at subnational levels influence tourism using paradiplomacy and city diplomacy concepts.
Juliane Santos Lumertz +3 more
wiley +1 more source
Research on Eddy Current Testing of Damages in Carbon Fiber Reinforced Polymers [PDF]
, 2015 碳纤维增强树脂基复合材料因其优异的性能已被广泛应用于飞行器制造、汽车制造、化学工业、造船与电气设备等各个行业，尤其是在航空航天、船舰以及核能设备等领域受到高度重视。然而，复合材料结构件在制造和使用过程中不可避免的会因为冲击等原因产生各种类型的缺陷。此外，复合材料结构件在损坏之前几乎没有先兆，其破坏具有突然性，这一点往往造成严重的后果。因此对碳纤维增强树脂基复合材料损伤的无损检测研究具有极其重要的意义。 目前应用较多的检测碳纤维增强树脂基复合材料损伤的方法有红外检测、X射线检测以及超声检测等 ...
杜飞
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Rare Metals, Volume 45, Issue 2, February 2026.ABSTRACT This study elucidates the oxidation mechanisms governing Y/Hf‐doped AlCoCrFeNiTi high‐entropy alloys (HEAs) and reveals the pivotal role of fabrication processes in dictating high‐temperature oxidation behavior. We demonstrate that casting and spark plasma sintering (SPS) promote Y/Hf segregation, resulting in heterogeneous oxide formation and
Huaqing Yi +5 more
wiley +1 more source
, 2008 Crack propagation is one of the key issues for simulating nonlinear behavior and evaluating safety of concrete structures. The equivalent crack opening displacement of smeared damage-fracture model is formulated with damage parameter and crack band width.
Long, Y, Zhang, C, Zhou, Y
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Rare Metals, Volume 45, Issue 1, January 2026.ABSTRACT Tungsten is inherently brittle and particularly prone to thermal stress concentration and crack formation during additive manufacturing processes such as laser cladding, which severely limits its engineering applications as a coating material. To address this issue, this study proposes an in situ toughening strategy involving the introduction ...
Guo‐Xing Chen +12 more
wiley +1 more source
Research on Si-based Ge micro-region structure and Ge lateral PIN photodetector [PDF]
, 2016 硅基光电探测器是硅基光电子技术重要的组成部分。近年来，锗（Ge）材料由于在近红外波段吸收系数高，空穴载流子迁移率大且能与硅基工艺兼容等特性在硅基探测器领域备受关注。为进一步提高光电特性，需要在Ge层中引入张应变，而张应变的引入可以通过微区结构来得到。基于硅基Ge外延材料，构造Ge微区结构的腐蚀过程一般只对Si材料的腐蚀速率有过研究，而对材料中存在的大量位错对结构制备影响的分析却并未开展。因此，研究腐蚀液中硅基Ge样品位错的影响，提高Ge微区结构应变，对提高Ge光电探测器性能有着重要的意义 ...
陈超文
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