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We proposed the conduction mechanism of organic light-emitting diode (OLED) using a one-dimensional discontinuous model. We assumed that each emitting molecule corresponds to a hopping site according to the actual charge transfer between adjacent molecules. Both carrier mobility of Alq3 and barrier heights for each carrier were derived from experimental data. We calculate transient behavior of carrier, field, and exciton distribution. Both carrier injections assumed the Schottky injection. In the previous results, when we assumed that calculated current density fit the experimental one in the current density field curve, calculated light-emission intensity did not fit the experimental one in the light-emission field curve. Furthermore, the slope of the calculated light emission-field curve is too small to fit the experimental one. In the previous study, hopping distance was assumed to be 1 nm. In this study, it is assumed to be 1.7 nm. We consider that field dependence of electron injection is too weak to explain only the Schottky emission. When the electron injection is assumed to be both Schottky emission and Fowler-Nordheim emission calculated light-emission field as well as the current-density field curves were fit to the curve of each experimental characteristics.

We investigated the space charge behavior near the interface between different low-density polyethylene (LDPE). Charge carriers were mainly injected from the semiconductive electrode in a specimen of Al/LDPE/LDPE/semiconductive layer and they moved through the interface to the counter Al electrode. Charge carriers moving from a lower density LDPE to a higher density one were accumulated near the interface to form space charge, while there was no space charge accumulation for carriers moving in the opposite direction. The mobilities of charge carriers were estimated from the change in space charge profile with time. Charge carriers are more mobile in the lower density LDPE than in the higher density one. Positive carriers were more mobile in LDPE than negative ones. The interface between different LDPE's greatly affected space charge behavior and discharging currents.

We have calculated the observed flux from a relativistic accretion disk rotating around a Schwarzschild black hole and oscillating radially near the inner edge.It is assumed that the surface temperature in the oscillating region varies sinusoidally.We found that the amplitude of relative flux becomes of the order of 2% when the amplitude of the surface temperture variation is 5%.Due to the relativistic effects,the amplitude of relative flux is slightly larger than that for the nonrelativistic case.In addition,the amplitude of X-ray flux is also larger than that of bolometric one., 我々はシュバルツシルト・ブラックホールの周りに形成された降着円盤が,中心のブラックホールに近いところで動径振動を起こした際の光度曲線を求めた。その際,振動領域における降着円盤の表面温度の変化は,正弦関数的変化であると仮定した。その結果,相対的な光度変化の振幅は,表面温度の変化の振幅を5%とした時に,約2%であった。非相対論的な場合に比べると,相対論的な効果によって,相対振幅は大きくなっている。また,X線強度変化は全波長強度変化より大きくなっている事が分かった。