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31.
An analytical expression for both band-to-band and band-trap-band indirect tunnelings is used to study the gate-induced drain leakage (GIDL) current of MOSFETs measured before and after hot-carrier stress. The voltage and temperature dependence of GIDL are characterized. Both results show that interface traps situated near the midgap participate in the conduction of GIDL, and band-trap-band indirect tunneling could be the major mechanism. This is further supported by the fact that the percentage increase in GIDL induced by hot-carrier stress is about the same as the corresponding increase in interface-trap density. On the other hand, under low-field conditions, trap-assisted Poole–Frenkle emission dominates over tunneling for temperatures even well below room temperature.  相似文献   
32.
Clinical manifestations and peripheral blood lymphocyte subset changes were studied in patients with myasthenia gravis (MG) to elucidate the mechanism of clinical improvement following treatment, with thymectomy (Tx) or glucocorticoid (GC) therapy. The changes found were: 1. There was a significant increase in percentages of CD3+, CD29+ CD4+ cells and CD4/CD8 ratio and a significant decrease in percentages of CD8+ and CD16,56+ cells in patients who had never been treated with any immune therapy. 2. After Tx or GC therapy, CD3+ and CD4+, CD29+ cells were decreased, but the number CD19+ and CD16, CD56 cells did not change. 3. Tx had a special effect on CD8+ cells. In most of the patients who showed clinical improvement after Tx, CD8+ cells were increased and CD4/CD8 ratio wad decreased. 4. Anti-acetylcholine receptor (AChRAb) titers were markedly decreased after GC therapy. These results indicate that there were obvious abnormalities in cell-mediated immunity in addition to those in humoral immunity in myasthenia gravis. These abnormalities tended to be normalized after Tx or GC therapy.  相似文献   
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Brambilla  G. Xu  F. Feng  X. 《Electronics letters》2006,42(9):517-519
It is demonstrated for the first time that long nanowires with radii as small as 30 nm can be manufactured with a conventional coupler fabrication rig. The temporal deterioration of nanowire optical properties has been studied and correlated with its mechanical behaviour. The original transmission properties have been restored by a post-fabrication treatment.  相似文献   
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A ten-user truly asynchronous gigabit coherent-optical-code-division-multiple-access (OCDMA) transmission was experimentally demonstrated without using any timing coordination. The enabling technologies are a record-length 511-chip superstructured-fiber-Bragg-grating (SSFBG) en/decoder and a supercontinuum (SC)-based optical-thresholding technique to significantly suppress the signal interference beat noise as well as the multiple-access-interference (MAI) noise.  相似文献   
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An analytical method is presented for calculating the resonant frequency andQ-factor of a superconducting dielectric disk resonator operating in millimeter-wave regime with whispering-gallery mode. Resonant frequency shift due to the optical generation of quasi-particles in superconducting film is investigated as a function of photon flux. An optically tunable resonant frequency of about 500 MHz is estimated, and good agreement is found between numerical results and experimental ones.  相似文献   
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文中解决了2-重自补图的计数问题,获得了具有p个顶点的2-重自补图的数目是其中Z(A)表示置换群A的圈指标,S ̄(2)_p表示p次对称群的对群.  相似文献   
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