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An anti-radiation structure of In P-based high electron mobility transistor(HEMT) has been proposed and optimized with double Si-doped planes. The additional Si-doped plane under channel layer has made a huge promotion in channel current, transconductance, current gain cut-off frequency, and maximum oscillation frequency of In P-based HEMTs. Moreover, direct current(DC) and radio frequency(RF) characteristic properties and their reduction rates have been compared in detail between single Si-doped and double Si-doped structures after 75-keV proton irradiation with dose of 5× 1011 cm-2,1× 1012 cm-2, and 5× 1012 cm-2. DC and RF characteristics for both structures are observed to decrease gradually as irradiation dose rises, which particularly show a drastic drop at dose of 5× 1012 cm-2. Besides, characteristic degradation degree of the double Si-doped structure is significantly lower than that of the single Si-doped structure, especially at large proton irradiation dose. The enhancement of proton radiation tolerance by the insertion of another Si-doped plane could be accounted for the tremendously increased native carriers, which are bound to weaken substantially the carrier removal effect by irradiation-induced defects. 相似文献
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为观察发育期氯化镧暴露对仔鼠嗅觉功能及β-Ⅲ微管蛋白表达的影响,将16只Wistar孕鼠随机分为两组(对照组、氯化镧组),对照组母鼠饮用蒸馏水,氯化镧组饮用0.25%氯化镧溶液;仔鼠出生后25d采用嗅觉迷宫试验检测仔鼠嗅觉功能的差异;于出生后28d采用免疫荧光和免疫印迹观察仔鼠β-Ⅲ微管蛋白在嗅上皮的表达变化。结果表明,氯化镧组仔鼠在嗅觉迷宫试验寻找食物的时间较对照组长,差异具有统计学意义(P〈0.05);氯化镧组下调仔鼠嗅上皮β-Ⅲ微管蛋白在嗅感觉神经元的表达。提示镧暴露损害子代嗅觉功能,可能与镧损害嗅上皮β-Ⅲ微管蛋白的表达有关。 相似文献
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为观察孕期和哺乳期铁缺乏对新生豚鼠听功能及耳蜗毛细胞形态结构的影响,将18只怀孕豚鼠按体质量随机分为3组,每组6只,分别是重度铁缺乏组、中度铁缺乏组和对照组;在仔鼠出生后第9天断乳,乙醚麻醉,畸变产物耳声发射( DPOAE)检测听力状况;分离耳蜗,行全基底膜铺片,用TRITC标记的鬼笔环肽染色,观察耳蜗毛细胞.结果表明... 相似文献
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利用推广后的Main和Spencer功能梯度板理论,研究了功能梯度矩形板在均布荷载作用下的柱面弯曲问题.采用该理论中的位移展开公式,并且材料参数沿板厚方向可以任意连续变化,但将材料由各向同性推广到正交各向异性,以及由不考虑板的横向荷载作用发展到受横向均布荷载作用.假设板在y方向无限长,从而得到了一个从弹性力学理论出发的正交各向异性功能梯度板在横向均布荷载作用下柱面弯曲问题的板理论.通过算例分析,讨论了边界条件和梯度变化程度对功能梯度板静力响应的影响. 相似文献
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