Results 21 to 30 of about 436 (68)

Seed–Habitat Thermal Interactions Contribute to the Mosaic Distribution Patterns of Invasive Chromolaena odorata and Ageratina adenophora in South Yunnan, China 种子与生境之间的热相互作用促成飞机草和紫茎泽兰在中国云南南部的镶嵌式分布

open access: yesIntegrative Conservation, Volume 4, Issue 1, Page 85-94, March 2025.
Chromolaena odorata and Ageratina adenophora are invasive species in Southern Yunnan, China; they have very differing, yet overlapping, climate niches. Both invaders produce a large number of small pappus‐bearing achenes every year. They grow in, and their seeds are dispersed to, both suitable and marginal habitats.
Bin Wen   +5 more
wiley   +1 more source

Uncovering Xi Jinping's Policy Agenda: Text As Data Approach

open access: yesThe Developing Economies, Volume 63, Issue 1, Page 9-46, March 2025.
How many agendas has Xi Jinping put forth and promoted since taking office in 2012, and what are the types of agendas? How much of political attention has each agenda received, and how has the allocation of attention changed over time? We utilize a dataset of presidential statements, speeches, and reports from 2012 to 2022 and employed automated text ...
Jaehwan Lim, Asei Ito, Hongyong Zhang
wiley   +1 more source

Resisting and Claiming Digital Sovereignty: The Cases of Civil Society and Indigenous Groups

open access: yesPolicy &Internet, Volume 16, Issue 4, Page 739-749, December 2024.
ABSTRACT In this contribution to “Unthinking digital sovereignty,” we review some discourses and practical proposals that resist or challenge the digital sovereignty of “established states.” Our focus centers on two distinct sociopolitical groups engaged in such practices.
Stéphane Couture   +2 more
wiley   +1 more source

ZnO压敏电阻在直流电压作用下老化劣化的分析

open access: yesDianci bileiqi, 2018
针对ZnO压敏电阻在直流电压作用下老化劣化的问题,通过对ZnO压敏电阻内部离子迁移和晶界肖特基势垒的理论分析。采用ZnO压敏电阻正极性直流作用和负极性直流交替作用的试验方法。利用理论与试验相结合,得出以下结论:1)老化前压敏电阻正、负极性伏安特性曲线几乎一致,没有产生极性效应;2)在单一正极性直流作用下,压敏电阻发生老化,且随时间和电流的增加,正极性老化程度大于负极性;3)在正、负极性直流交替作用下,压敏电阻老化时间推迟,程度减小,压敏电压和漏电流变化趋势较单一正极性趋势减弱,且极性效应趋于消失;4 ...
李祥超, 马骁骐
doaj  

Personalized medicine in China: An overview of policies, programs, and actions in China 中国的个性化医学:关于中国政策、计划和行动的概述 Medicina personalizada en China: Una descripción general de las políticas, programas y acciones en China

open access: yesWorld Medical &Health Policy, Volume 16, Issue 4, Page 558-576, December 2024.
Abstract Background Over the past decade, the ascent of personalized medicine (PM) has catalyzed pivotal transformations in healthcare systems on a global scale. Recognizing its crucial importance, the European Commission has prioritized PM within its research directives, allocating funding for international collaborative projects, such as the ...
Marzia Di Marcantonio   +6 more
wiley   +1 more source

复合绝缘子HTV硅橡胶伞套的湿热老化特性研究

open access: yesDianci bileiqi, 2020
由于长期运行在湿热的气候环境下,近年来我国南方地区复合绝缘子异常发热、击穿断裂等故障时有发生,严重威胁了电网的安全稳定运行。为了研究复合绝缘子硅橡胶伞套的湿热老化特性,首先对高温硫化(High Temperature Vulcanization,HTV)硅橡胶进行湿热老化实验,然后利用扫描电镜、红外光谱、热重分析、介电谱和热刺激电流测试等分析手段对湿热老化和运行老化样品进行微观分析,结果表明:湿热的联合作用能够显著加速HTV硅橡胶的老化进程,随着湿热老化时间的增加,样品的表面微观形貌、化学基团、热解性能、
曾磊磊   +9 more
doaj  

高压电缆绝缘热老化特性及破坏机理研究

open access: yesGaoya dianqi, 2023
高压电缆长期运行过程中温度引起的绝缘材料热老化是影响其整体绝缘性能的重要因素。通过对高压电缆主绝缘层切片取样,研究分析了不同老化程度试样的微观形貌、官能团、结晶度、交联度等理化性能变化规律,测试分析了不同老化程度试样的电阻特性、介电性能和击穿特性,仿真模拟了不同温度下交联聚乙烯分子链的运动情况,进一步讨论了热老化对其微观结构的破坏演变机理。研究结果表明,老化2 160 h后试样的晶区结构破坏较为严重,随着老化时间的延长,相邻晶区的间距增大,晶区排列松散,无定型区面积增大;羰基指数从3.88%增大至11 ...
王兆琛   +6 more
doaj  

Indexical deprivation: The dominant link between cochlear implants and global English among Taiwanese deaf individuals

open access: yesJournal of Linguistic Anthropology, Volume 34, Issue 3, Page 441-469, December 2024.
Abstract This paper develops the concept of “indexical deprivation” from the experiences of English learning in relation to cochlear implant use among Taiwanese deaf adults. Based on the framework of language ideological assemblage, this paper traces how institutional discourses and practices at different levels contribute to the indexicalization ...
Tsung‐Lun Alan Wan
wiley   +1 more source

Incidence and dynamics of mobility device use among community‐dwelling older adults in the United States

open access: yesJournal of Elder Policy, Volume 3, Issue 2, Page 70-94, October 2024.
Abstract Mobility devices are crucial in enhancing activities and participation for individuals with mobility disability, particularly among the rapidly expanding population of older adults worldwide. This paper explores patterns of mobility device use among a nationally representative cohort of community‐dwelling older adults in the United States ...
Xinran Liu   +5 more
wiley   +1 more source

高温硫化硅橡胶材料的运行特性及分析

open access: yesDianci bileiqi, 2006
对大量运行的高温硫化硅橡胶(HTV)绝缘子进行了憎水性试验、低温模拟试验、灰密对憎水性的影响以及耐漏电起痕及电蚀损试验,认为高温硫化硅橡胶因老化而引起的憎水性下降、机械强度下降及积污性能下降影响其长期工作的可靠性,所以评价复合硅橡胶的憎水性能除憎水性分级HC值外,还应重点突出评价憎水性的减弱(丧失)特性、憎水性的恢复特性及憎水性的迁移特性。低温模拟试验表明,低温下憎水性有一定程度的下降,应针对性地开发应用于低温地区的高温硫化硅橡胶,并制订新的判定准则。最后对硅橡胶材料老化试验方法进行了讨论 ...
张予, 吴光亚, 张锐
doaj  

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