کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
5360183 | 1388257 | 2009 | 6 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Characteristics of polymer velvet as field emitters under high-current pulsed discharge
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کلمات کلیدی
موضوعات مرتبط
مهندسی و علوم پایه
شیمی
شیمی تئوریک و عملی
پیش نمایش صفحه اول مقاله
![عکس صفحه اول مقاله: Characteristics of polymer velvet as field emitters under high-current pulsed discharge Characteristics of polymer velvet as field emitters under high-current pulsed discharge](/preview/png/5360183.png)
چکیده انگلیسی
In this paper we investigated the surface morphology and emission property of polymer velvet in a cathode test system powered by a â¼400Â ns, â¼400Â kV pulsed generator. After a series of pulse shots, the velvet surface exhibited an obvious decrease in the amount of emitters, namely, the smoothing of microprotrusions, indicating a lower field enhancement factor or a higher turn-on electric field than that for no shots. As the velvet cathode lifetime proceeded, the beam degradation was observed in terms of the voltage pulse length, maximum emission current, and rise time of diode current. Further, the average current density significantly decreased during a 100 pulse shot test, from 280 to 160Â A/cm2. The surface discharge caused many plasma spots on the velvet surface. The cathode plasma expands towards the anode, directly leading to the diode gap closure. The degradation in the velvet performance after high-current emission may be related to this behavior of cathode plasma. Finally, the electron emission mechanisms, how to affect the surface morphology of velvet, are presented.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Applied Surface Science - Volume 255, Issue 8, 1 February 2009, Pages 4563-4568
Journal: Applied Surface Science - Volume 255, Issue 8, 1 February 2009, Pages 4563-4568
نویسندگان
Limin Li, Lie Liu, Lei Chang, Hong Wan, Jianchun Wen, Yonggui Liu,