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Equine Veterinary Journal, Volume 57, Issue 4, Page 1053-1064, July 2025.Abstract Background In Great Britain, owners are keeping their horses into increasingly older age, reflecting societal changes in human–animal relationships. The uptake of routine veterinary services is reported to reduce as horses age. Horse owners seek information regarding their animal's health from alternative sources before and/or following ...
Rebecca Smith +4 more
wiley +1 more source
Dianci bileiqi, 2014 针对ZnO压敏电阻经受多次8/20雷电流冲击后交流老化特性变化的问题,通过对ZnO压敏电阻老化机理的理论分析,并对ZnO压敏电阻样品进行不同次数的冲击老化实验后再进行交流老化实验测量其静态参数的变化,发现适当次数的大电流冲击会增强ZnO压敏电阻的交流耐受能力;ZnO压敏电阻的U1 mA和U0.1 mA在交流老化过程中呈现小幅上升、缓慢下降、快速减小的趋势,非线性系数则呈现持续缓慢降低而后快速下降的趋势;根据实验结果,得出电子陷阱及离子迁移是交流老化初始和中期的主要老化机理,而热破坏在老化末期起主要作用。
陈璞阳 +4 more
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Gaoya dianqi, 2022 为研究热老化下介质直流和操作冲击结果的演变规律及其影响机制，文中以热老化处理的（190℃，220℃）双层聚酰亚胺薄膜（PI）为研究对象，采用等温松弛电流法（IRC）对不同热老化程度介质的空间电荷特性进行研究，基于双极性电荷输运模型（BCT），仿真研究陷阱密度对直流击穿结果的影响机制。基于局域态电荷吸收能量的频率依赖模型，数值分析空间电荷和介电参量对冲击击穿结果的影响机理。结果表明，随着热老化时间增加，介质陷阱密度逐渐减小，电荷注入效应增强，介质内部的电场畸变程度增大，故直流击穿场强逐渐下降 ...
梅冰笑 +4 more
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Integrative 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
Dianci bileiqi, 1998 从非欧姆导电机理、老化机理的深化和完善、功能微观结构作用和控制、粉料预处理和制造技术等方面对zno压敏电阻片的基础理论研究进行了概括；并指出，从技术发展动态看，主要是降低残压比、提高单位体积的能量耐受能力、提高压敏电位梯度、提高长期老化性能。
1.西安交通大学电气绝缘研究所!西安 +1 more
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Dianci bileiqi, 2023 酥朽断裂是如今高压输电线路中复合绝缘子的新型机械故障，现有的研究均集中于酥朽断裂绝缘子芯棒的老化过程和理化特性，但很少有研究在实验室试验中模拟这种现象。建立了一种具有高温，酸腐蚀和高电场强度等多种老化条件的人工加速老化平台，一定程度上模拟了酥朽断裂绝缘子芯棒的典型特征。结果表明，当施加电压数小时后，使用热红外成像仪检测发现温度明显升高。与单一老化应力相比，芯棒样片在多应力条件下的温度高达61℃。此外，采用扫描电子显微镜(SEM),傅立叶变换红外(FTIR)光谱，X射线光电子能谱(XPS)和热重分析 ...
蔡汉贤 +5 more
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Uncovering Xi Jinping's Policy Agenda: Text As Data Approach
The 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
Fuel Cell Perofrmance and Degradation Mechanism of Carbon Supported Ruthenium Selenide [PDF]
, 2012 电催化剂是质子交换膜燃料电池正常运行的关键材料之一，铂基贵金属电催化剂价格昂贵，且阴极氧还原反应产生的过电位较大，严重制约燃料电池商业化。钌硒化合物具有较好的氧还原反应催化活性，成本较铂低，可抗有机小分子毒化，有望作为替代铂基材料的阴极催化剂。因此，有必要探讨钌硒催化剂和膜电极组的最佳制备条件，获得最佳的电池性能和寿命，并对催化剂及膜电极组的性能影响因素进行系统的分析，可为研究和开发价格低廉、高性能和高稳定性的非铂阴极催化剂提供科学依据。 本论文采用微波辅助合成法制备了碳载钌硒催化剂 ...
郑巧明
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Conservation Biology, Volume 38, Issue 6, December 2024.Abstract Free, prior, and informed consent (FPIC) is now a globally established norm and is a condition of equitable engagement with Indigenous peoples and local communities in biodiversity conservation. However, implementation is frequently questioned in terms of its efficacy in top‐down‐driven governance contexts.
Peter Bille Larsen +1 more
wiley +1 more source
Gaoya dianqi, 2018 为研究某500 kV变电站硅橡胶辅助伞裙粉化、脆化、塌陷甚至断裂脱落的原因,以此变电站的老化伞裙为研究对象,采用憎水性、机械性能测试,扫描电子显微镜、X射线光电子能谱、红外光谱、热失重分析等多种技术进行理化特性分析和老化评估。结果表明,相比于新伞裙,老化伞裙的憎水性、机械性能已大幅度退化。硅橡胶在外界环境作用下发生复杂的物理化学变化,分子链断链并生成了大量强极性活性基团,同时有机组分流失,形成微孔洞结构,使硅橡胶伞裙性能下降。伞裙配方不够合理也可能是较快劣化、性能下降的原因 ...
吴俊杰 +5 more
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