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Russian Text Ignored 《等离子体物理论文集》1978,18(6):393-410
A nonlinear theory of the interaction of an external pump field with ion-acoustic and h.f. surface waves in a plasma layer with inhomogeneous boundary regions is presented for the case, when the pump field frequency is less than the electron plasma frequency. The evolution of the parametrically excited turbulence and its stationary state are both analytically treated and numerically demonstrated. Dependent on the pump field strength, two mechanisms are to be distinguished: (i) nonlinear generation of damped ion-acoustic harmonics, (ii) cascade excitation of secondary eigenmodes by growing surface oscillations. At only slight overthreshold values, mechanism (i) is responsible for the occurence of the steady state, whereas, for higher pump field strength, the wave amplitudes as well as their saturated levels are mainly determined by mechanism (ii). 相似文献
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Y.R. Liu Author Vitae J.B. Peng Author Vitae P.T. Lai Author Vitae 《Applied Surface Science》2007,253(17):6987-6991
Polymer thin-film transistors (PTFTs) based on poly(2-methoxy-5-(2′-ethyl-hexyloxy)-1,4-phenylene vinylene) (MEH-PPV) semiconductor are fabricated by spin-coating process and characterized. In the experiments, solution preparation, deposition and device measurements are all performed in air for large-area applications. Hysteresis effect and gate-bias stress effect are observed for the devices at room temperature. The saturation current decreases and the threshold voltage shifts toward the negative direction upon gate-bias stress, but carrier mobility hardly changes. By using quasi-static C-V analysis for MOS capacitor structure, it can be deduced that the origin of threshold-voltage shift upon negative gate-bias stress is predominantly associated with hole trapping within the SiO2 gate dielectric near the SiO2/MEH-PPV interface due to hot-carrier emission. 相似文献
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Recent developments in the aerobic oxidation of alcohols 总被引:1,自引:0,他引:1
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Hélène Pellissier Author Vitae 《Tetrahedron》2007,63(16):3235-3285
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