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Developmental Medicine &Child Neurology, Volume 61, Issue 3, Page E1-E35, March 2019., 2019 目的 本国际临床指南由欧洲残疾儿童学会（the European Academy of Childhood Disability，EACD）牵头制定，旨在解决发育性协调障碍（developmental coordination disorder，DCD）的定义、诊断、评估、干预以及与社会心理方面的临床应用关键问题。 方法 本指南针对五个领域的关键问题，通过文献综述和专家团队的正式讨论达成共识。为保证指南的循证基础，以“机制”、“评估”和“干预”为检索词, 对2012年更新以来提出的最新建议以及新增的“社会心理问题”和“青少年/成人”为检索词进行检索。根据牛津大学循证医学中心证据等级 (证据水平 [level of evidence, LOE]1–4) 将结果进行分类，最终转化为指南建议。并由国际 ...
Jing Hua +6 more
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, 2021 超低损耗光纤被认为是实现400 Gbit/s甚至1 Tbit/s超高速光纤传输的关键。目前，已存在大量的关于超低损耗光纤技术的研究。为帮助读者更系统全面地了解该类光纤的技术现状，文章介绍了相关的制备技术、产业现状、应用研究以及未来技术方向等多个方面，希望能为大家提供有用的技术信息 ...
刘志忠 +10 more
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Dianci bileiqi, 2020 变压器绝缘套管中实际加载的电压波形中谐波成分含量较高,为了探究电压谐波对变压器套管电容芯子介质损耗的影响,基于频域有限元法建立了220 k V电容式变压器套管的有限元模型,获得了变压器套管电容芯子绝缘介质的非线性频变特性曲线,并进一步考虑了电容芯子介电常数频变特性对其介质损耗发热的影响。在给定波形参数下,电容芯子在谐波作用下的频变特性对介质损耗发热的增强系数仅为0. 27%,高次谐波对电容芯子的介质损耗发热影响较小。研究结果对于电容式套管的介质损耗发热和其事故分析具有一定的参考价值。
夏军 +4 more
doaj
, 1982 光纤心线大多数采用预涂、缓冲,套塑三层涂覆结构。由于涂料特性易随温度变化,使得光纤心线损耗在高温和低温下都大于室温时的值。本文介绍套塑材料在高温下再结晶和分子取向改变引起的损耗增大和低温下冷缩引起的损耗增大以及涂料特性、涂覆条件和光纤参数对损耗增大程度的影响 ...
李先源
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Rare Metals, Volume 45, Issue 6, June 2026.ABSTRACT To address the demand for high‐temperature stability, broadband strong absorption, and multifunctional integration of electromagnetic wave absorbing materials in complex service environments, lightweight molybdenum disulfide (MoS2) decorated silicon carbide (SiC) nanofiber composite aerogels with a directional layered interconnected structure ...
Zhi Song +4 more
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Rare Metals, Volume 45, Issue 6, June 2026.ABSTRACT The development of lightweight, high‐attenuation, and broadband carbon‐based electromagnetic wave absorbers is hindered by the intrinsic trade‐off between impedance matching and dielectric dissipation. Herein, we report a facile and scalable synthesis of N‐doped lignin‐derived interconnected porous carbon (Nx‐LIPC) via hydrogen‐bond self ...
Bin‐Peng Zhang +7 more
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Rare Metals, Volume 45, Issue 6, June 2026.ABSTRACT Dielectric polymers commonly suffer from severe performance degradation above 150°C, hindering advanced power systems. Herein, we demonstrate a polyetherimide (PEI) nanocomposite that overcomes this by mimicking the gradient architecture of nacre and bamboo, incorporating a continuous vertical gradient of fluorinated boron nitride nanosheets ...
Jian Wang +8 more
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Rare Metals, Volume 45, Issue 3, March 2026.ABSTRACT Emerging as attractive alternatives for sustainable, low‐cost, and high‐performance electromagnetic interference (EMI) shielding, biomass‐derived carbon is nonetheless constrained by a limited repertoire of shielding mechanisms. Herein, a straightforward method was employed to synthesize self‐supporting Co nanoparticles embedded in porous N ...
Yingjie Xu +6 more
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Rare Metals, Volume 45, Issue 2, February 2026.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
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, 1980 <正> 光纤传输特性中最重要的是传输带宽和传输损耗。带宽主要受多模色散、材料色散和结构色散的限制。传输损耗主要由光纤材料的固有吸收、杂质吸收 ...
溯源
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