Mechanism analysis of gate-induced drain leakage in off-state n-MOSFET

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.     

Effects of thymectomy and glucocorticoid therapy on peripheral lymphocytes in myasthenia gravis

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.     

Fabrication of optical fibre nanowires and their optical and mechanical characterisation

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.     

Ten-user truly asynchronous gigabit OCDMA transmission experiment with a 511-chip SSFBG en/decoder

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.     

Effect of temperature on methyl radical generation over Sr/La2O3 catalysts

The role of gas phase CH₃ radicals in the oxidative coupling of CH₄ over 1 wt% Sr/La₂O₃ is supported by the observations that (i) this is a very effective catalyst for the generation of CH₃ · radicals and (ii) the concentration of CH₃ · radicals increases with temperature over the range of 450 °C–800 °C.     

Electromagnetic properties of ferroelectric-ferrite ceramic composites

The NiFe₂O₄ and Pb(Zr_0.52Ti_0.48)O₃ ceramic composites are prepared by conventional solid state reaction method. The microstructural and morphological properties of the composites are studied by X-ray diffraction analysis and scanning electron microscopy. Results indicate that the ferrite and piezoelectric phases can co-exist in the composites. The relationship between the dielectric constant and frequency (40 Hz–40 MHz) as well as temperature is also investigated. It is noted that the transition temperature of the composites is about 380 °C. A double electric hysteresis loop is observed in our composites. The magnetic properties are relatively weak according to the magnetic hysteresis loop. With increase in the content of the ferrite phase, the permeability increases. The electromagnetic properties of the as-prepared composites are tunable according to the content of the NiFe₂O₄ phase.