针对空间应用,开展SiC MOSFET单粒子效应试验研究。在加速器上用重离子辐照1200 V SiC MOSFET,离子线性能量传输(LET)在0.26~118 MeV·cm^(2)/mg之间,辐照中被试器件加50~600 V静态漏源偏置电压、栅源短接,实时测量电特性,进行辐照...针对空间应用,开展SiC MOSFET单粒子效应试验研究。在加速器上用重离子辐照1200 V SiC MOSFET,离子线性能量传输(LET)在0.26~118 MeV·cm^(2)/mg之间,辐照中被试器件加50~600 V静态漏源偏置电压、栅源短接,实时测量电特性,进行辐照后栅应力(PIGS)测试。试验结果发现,50~100 V偏置电压下,离子引起瞬态电流,PIGS测试栅失效。分析认为离子引起栅氧化物潜在损伤,PIGS测试过程中,潜在损伤进一步退化导致栅失效。氧化物潜在损伤不仅与辐照偏置电压有关,还与入射离子LET和注量有关。PIGS测试需要的栅应力时间与潜在损伤程度有关,可超过300 s。并给出了电荷累积损伤模型。模型进行SiC MOSFET单粒子效应评估时,应考虑离子引起栅氧化物潜在损伤的影响,需根据轨道和任务周期确定试验离子注量,根据应用情况确定辐照偏置电压,并评估确定PIGS测试栅应力时间。展开更多
This paper explores Du Boisian notion of double consciousness and the notion of black nihilism suggested by Cornel West in Ralph Ellison＇s Invisible Man （1952） and August Wilson＇s Fences （1986）. In order to cond...This paper explores Du Boisian notion of double consciousness and the notion of black nihilism suggested by Cornel West in Ralph Ellison＇s Invisible Man （1952） and August Wilson＇s Fences （1986）. In order to conduct this study, the researcher adopts African American approach and shows that double consciousness and black nihilism are the immediate effects of African Americans＇ marginalisation. According to W. E. B. Du Bois, all African Americans develop the sense of double consciousness which means being both African and American simultaneously. On the other hand, Cornel West believes that black Americans suffer from nihilism which means loss of hope and absence of meaning. The paper is an attempt to compare the novel Invisible Man and the play Fences thematically based on these two theories. It then looks to find the considerable similarities in the conditions of the protagonists of these two literary works. Although both protagonists migrate to the North to escape Southern racism in the era prior to the Civil Rights Movement, they become totally disillusioned, for they are treated as the invisible marginal. Interestingly though, at the end of both stories, there remains a ray of hope for reactivation and the creation of democracy for black Americans.展开更多
The authors review their recent advances in the development of optical fiber Bragg grating （FBG） sensor technologies. After a brief review of the fiber grating sensors, several newly developed FBG sensors are descri...The authors review their recent advances in the development of optical fiber Bragg grating （FBG） sensor technologies. After a brief review of the fiber grating sensors, several newly developed FBG sensors are described. With the continuous development of fiber materials, microstructures and post-processing technologies, FBG sensors are still creative after the first demonstration of permanent gratings thirty years ago.展开更多
文摘针对空间应用,开展SiC MOSFET单粒子效应试验研究。在加速器上用重离子辐照1200 V SiC MOSFET,离子线性能量传输(LET)在0.26~118 MeV·cm^(2)/mg之间,辐照中被试器件加50~600 V静态漏源偏置电压、栅源短接,实时测量电特性,进行辐照后栅应力(PIGS)测试。试验结果发现,50~100 V偏置电压下,离子引起瞬态电流,PIGS测试栅失效。分析认为离子引起栅氧化物潜在损伤,PIGS测试过程中,潜在损伤进一步退化导致栅失效。氧化物潜在损伤不仅与辐照偏置电压有关,还与入射离子LET和注量有关。PIGS测试需要的栅应力时间与潜在损伤程度有关,可超过300 s。并给出了电荷累积损伤模型。模型进行SiC MOSFET单粒子效应评估时,应考虑离子引起栅氧化物潜在损伤的影响,需根据轨道和任务周期确定试验离子注量,根据应用情况确定辐照偏置电压,并评估确定PIGS测试栅应力时间。
文摘This paper explores Du Boisian notion of double consciousness and the notion of black nihilism suggested by Cornel West in Ralph Ellison＇s Invisible Man （1952） and August Wilson＇s Fences （1986）. In order to conduct this study, the researcher adopts African American approach and shows that double consciousness and black nihilism are the immediate effects of African Americans＇ marginalisation. According to W. E. B. Du Bois, all African Americans develop the sense of double consciousness which means being both African and American simultaneously. On the other hand, Cornel West believes that black Americans suffer from nihilism which means loss of hope and absence of meaning. The paper is an attempt to compare the novel Invisible Man and the play Fences thematically based on these two theories. It then looks to find the considerable similarities in the conditions of the protagonists of these two literary works. Although both protagonists migrate to the North to escape Southern racism in the era prior to the Civil Rights Movement, they become totally disillusioned, for they are treated as the invisible marginal. Interestingly though, at the end of both stories, there remains a ray of hope for reactivation and the creation of democracy for black Americans.
文摘The authors review their recent advances in the development of optical fiber Bragg grating （FBG） sensor technologies. After a brief review of the fiber grating sensors, several newly developed FBG sensors are described. With the continuous development of fiber materials, microstructures and post-processing technologies, FBG sensors are still creative after the first demonstration of permanent gratings thirty years ago.
