丙烯碳酸盐(PC ) 有一个大潜力在搏动的力量由于它的高绝缘的常数和大抵抗力采购的协议被用作精力存储媒介。我们两个都调查 PC 的积极、否定的故障特征。streamer 模式被极端高速度的照相机获得。试验性的结果证明 PC 的积极故障电压...丙烯碳酸盐(PC ) 有一个大潜力在搏动的力量由于它的高绝缘的常数和大抵抗力采购的协议被用作精力存储媒介。我们两个都调查 PC 的积极、否定的故障特征。streamer 模式被极端高速度的照相机获得。试验性的结果证明 PC 的积极故障电压比否定的高是大约 135% ,它与普通液体相比是反常的。积极 streamer 的形状细丝、多枝,当否定 streamer 像树、不太分叉时。根据这些试验性的结果,在在金属电极和液体之间的接口的一个费用层结构模型被介绍。反常极性效果基本上在在电极和 PC 之间的接口从电场力量差别产生,这被建议。而且,再结合放射和光电游离也在整个分泌物过程起一个重要作用。展开更多
Research on aging characteristics of epoxy resin(EP) under repetitive microsecond pulses is important for the design of insulating materials in high power apparatus.It is because that very fast transient overvoltage a...Research on aging characteristics of epoxy resin(EP) under repetitive microsecond pulses is important for the design of insulating materials in high power apparatus.It is because that very fast transient overvoltage always occurs in a power system,which causes flashover and is one of the main factors causing aging effects of EP materials.Therefore,it is essential to obtain a better understanding of the aging effect on an EP surface resulting from flashover.In this work,aging effects on an EP surface were investigated by surface flashover discharge under repetitive microsecond pulses in atmospheric pressure.The investigations of parameters such as the surface micro-morphology and chemical composition of the insulation material under different degrees of aging were conducted with the aid of measurement methods such as atomic force microscopy(AFM),scanning electron microscopy(SEM),and X-ray photoelectron spectroscopy(XPS).Results showed that with the accumulation of aging energy on the material surface,the particles formed on the material surface increased both in number and size,leading to the growth of surface roughness and a reduction in the water contact angle; the surface also became more absorbent.Furthermore,in the aging process,the molecular chains of EP on the surface were broken,resulting in oxidation and carbonisation.展开更多
基金Supported by the National Natural Science Foundation of China under Grant Nos 61275157 and 61475040, the National Instrumentation Program of China under Grant No 2012YQ120048, and the National Development Project for Major Scientific Research Facility under Grant No ZDYZ2012-2.
文摘一条频率稳定途径基于与一快高精确的波长米连接的一个控制计算机的反馈系统用 intracavity 倾斜调节和调节温度的 etalon 为微秒脉搏钠烽火激光被介绍。钠烽火激光的频率稳定性与循环控制相比并且没有反馈。激光的输出波长与控制技术的反馈循环在 12 h 上被锁到钠 D 吸收线(589.159 nm ) 。作为结果,钠激光指南星被国家天文台的望远镜成功地在 Xinglong 观察。这条途径能也为频率稳定被用于另外的脉搏和连续波浪的激光。
基金Supported by the National Natural Science Foundation of China under Grant No 51677190, and the Hunan Provincial Natural Science Foundation of China under Grant No 2017JJ1005.
文摘丙烯碳酸盐(PC ) 有一个大潜力在搏动的力量由于它的高绝缘的常数和大抵抗力采购的协议被用作精力存储媒介。我们两个都调查 PC 的积极、否定的故障特征。streamer 模式被极端高速度的照相机获得。试验性的结果证明 PC 的积极故障电压比否定的高是大约 135% ,它与普通液体相比是反常的。积极 streamer 的形状细丝、多枝,当否定 streamer 像树、不太分叉时。根据这些试验性的结果,在在金属电极和液体之间的接口的一个费用层结构模型被介绍。反常极性效果基本上在在电极和 PC 之间的接口从电场力量差别产生,这被建议。而且,再结合放射和光电游离也在整个分泌物过程起一个重要作用。
基金supported by the Natural Science Foundation of Hebei Province (No. E2015502081), National Natural Science Foundation of China (Nos. 51222701, 51307060), and the National Basic Research Program of China (No. 2014CB239505-3)
文摘Research on aging characteristics of epoxy resin(EP) under repetitive microsecond pulses is important for the design of insulating materials in high power apparatus.It is because that very fast transient overvoltage always occurs in a power system,which causes flashover and is one of the main factors causing aging effects of EP materials.Therefore,it is essential to obtain a better understanding of the aging effect on an EP surface resulting from flashover.In this work,aging effects on an EP surface were investigated by surface flashover discharge under repetitive microsecond pulses in atmospheric pressure.The investigations of parameters such as the surface micro-morphology and chemical composition of the insulation material under different degrees of aging were conducted with the aid of measurement methods such as atomic force microscopy(AFM),scanning electron microscopy(SEM),and X-ray photoelectron spectroscopy(XPS).Results showed that with the accumulation of aging energy on the material surface,the particles formed on the material surface increased both in number and size,leading to the growth of surface roughness and a reduction in the water contact angle; the surface also became more absorbent.Furthermore,in the aging process,the molecular chains of EP on the surface were broken,resulting in oxidation and carbonisation.