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We found the estimated use of tiger bone glue within the last 12 months to be 6.9%. We found a stated motivation of taking TBG to improve health, and by the suggestion of one's social group. We suggest reducing the acceptability of TBG as medicine and encouraging non‐animal‐based medicinal alternatives.
Elizabeth Oneita Davis +5 more
wiley +1 more source
为了能够实现对变压器油纸绝缘老化状态的准确评估,文中在极化/去极化电流方法的基础上,提出6种表征油纸老化的特征量,并将动态贝叶斯网络引入到油纸绝缘老化状态评估问题中,建立了相应的老化阶段预测模型,针对该模型进行了实例验证。结果表明:从PDC及拓展Debye模型提取的绝缘纸电量Qpaper、稳定平均电导电流■以及平均极化时间常数■对油纸老化状态反映敏感,且与聚合度有良好的拟合关系,可作为表征绝缘纸老化的特征量;油纸绝缘老化状态评估问题符合动态贝叶斯网络的应用条件,通过划分特征量状态及老化阶段 ...
吴晋媛 +4 more
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为提取表征油纸绝缘老化状态特征参量,将时域介电法更好地应用于油纸绝缘老化状态无损检测,在实验室条件下对不同老化程度的油纸绝缘试样进行极化去极化电流法(PDC)试验,并求得其等效模型参数;然后提出系统极点Pi作为油纸绝缘老化特征参量,并建立其与油纸绝缘老化状态关系;最后验证了系统极点用于评估油纸绝缘老化程度评估的可行性。研究结果表明:扩展Debye模型参数对油纸绝缘老化程度比较敏感,特别是时间参数大于1 000 s的极化支路,其时间常数随着老化时间的增加而呈现递增规律;对于时间常数大于1 000 ...
陈明星 +4 more
doaj
ABSTRACT Sub‐Saharan Africa (SSA)'s infrastructure deficit is not fundamentally a consequence of insufficient capital but rather of legal and institutional failure. This article argues that law is a decisive factor in determining whether infrastructure finance becomes possible, functioning not merely as a background condition but as a mechanism through
Augustine Edobor Arimoro
wiley +1 more source
ABSTRACT Aqueous vanadium dioxide (VO2)‐based smart thermal insulation coatings represent a viable strategy to decrease building energy consumption and advance sustainable development goals. However, the inherent instability and limited compatibility with polymer matrices of VO2 hinder its widespread application.
Xiuxian Zhao +9 more
wiley +1 more source
ABSTRACT Population aging is a problem that countries around the globe are facing; it comes with complex healthcare needs. Different countries take different approaches to solving these issues. In the United States, proposed legislation related to hospice and palliative care emerged from a history of hospice fraud and specialty physician shortages.
Edith‐Marie Green
wiley +1 more source
为分别评估变压器油纸绝缘的老化程度和水分含量,文中通过加速热老化试验和吸潮实验制备了不同老化程度下含水量不同的油浸绝缘纸试品,测试了试品的介损因数频谱和阻抗相位频谱,分析了老化、水分对油纸绝缘频域介电谱特性的影响。采用多输出支持向量回归算法(multi-output support vectorregression,M-SVR)逼近频域介电谱曲线与油纸绝缘老化和水分之间的非线性映射关系,据此预测油纸绝缘试品的老化程度和水分含量。研究表明,对于含水量在0.5~5.6%范围内、具有不同老化程度的试品,M ...
杨飞豹 +5 more
doaj
交联聚乙烯(XLPE)电力电缆广泛应用于配电网和输电网,但它们在持续的电应力下遭受长期的老化退化,电缆老化容易造成绝缘击穿事故。为了提升电缆绝缘老化状态的在线评估技术,基于PSCAD建立了计及电缆绝缘不均匀老化的三芯管型电缆接地电流相位角计算模型,通过快速傅里叶变换FFT变化得到单相不均匀老化、双相不均匀老化、三相均匀老化3类情况的接电线电流相位角特性。结果表明:相比于钢铠接地线电流,屏蔽线电流相角对于老化特性的反应更为灵敏;对于单相老化,介电常数由2增加为5,屏蔽线电流相位角从-51.01°递增为 ...
刘刚 +5 more
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通过对硅橡胶材料的表面腐蚀、化学腐蚀以及老化引起污秽层形成这3种老化途径的机理分析,表明硅橡胶具有极好的抗老化性。同时,指出漏流径形成是造成硅橡胶老化的最主要原因。盐雾试验证明,老化引起绝缘性能降低后,经过一段时间,硅橡胶表现出本身具有自恢复性。
田可新
doaj
实验室中常采用加速老化方法获得硅油的老化试样,并根据试样中溶解气体组分及体积分数判断硅绝缘油的老化状态,但当前实验中仅能施加热应力或电应力,不能较好地反映硅油的真实工况。为解决这这一问题,文中开展了电热应力对硅油产气特性协同效应的实验研究。文中针对PMX-200型硅油,在200 ℃、25 kV下设计了硅油的热电老化、电热老化和电热联合老化等3组加速老化实验,通过对试样中的气体组分及体积分数分析,发现热电老化方式与电热联合老化方式下试样中溶解气体组分及体积分数最为接近,误差在7.41%~16.86%之间 ...
连鸿松 +4 more
doaj

