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一种600V VDMOS终端保护环结构的设计 总被引:1,自引:0,他引:1
本文详细讨论了VDMOS终端保护环结构各部分,即保护环、保护环间隙和场板的作用及设计方法。结合600VVDMOS的外延电阻率和厚度,一种600VVDMOS终端保护环结构被成功设计出来。 相似文献
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Björn Michelberger Frederic Schell Dirk Jaitner Andreas Götze Beate Leupolt Franz-Josef Wetzel Andreas Leson Andrés F. Lasagni 《Advanced Engineering Materials》2023,25(14):2201708
Internal combustion engines are increasingly regulated in regard to efficiency and environmental impact, which requires advanced optimization strategies of engine components. The contact between the top ring and the cylinder liner is critical to the efficiency of an internal combustion engine. As shown in a previous study, an amorphous carbon coating can greatly improve the friction properties of piston rings. This work expands on these results by fabricating laser-interference-induced microchannels on the coating perpendicular to the direction of movement with a mean depth of 0.97 and 3.13 μm spatial period to further optimize the tribology. Fired single-cylinder engine measurements of the microtextured rings show a significant reduction in mean piston assembly friction of 5% for operation points that are relevant for urban transportation and up to 10% for specific operation points. Subsequent multibody elastohydrodynamic simulations prove that measured friction changes result from the compression ring microtexture. In particular, the microtexture increases the hydrodynamic pressure, reduces hydrodynamic losses, and leads to 20% lowered compression ring losses for an entire combustion cycle of the investigated operation point. In the future, such tribological concepts can be deployed in internal combustion engines that are powered by sustainable hydrogen or methanol. 相似文献
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Hao-Yu Shen Wei-Ming Bu Dai-Zheng Liao Zong-Hui Jiang Shi-Ping Yan Geng-Lin Wang 《Inorganic chemistry communications》1999,2(12):1291
A hydrogen-bonded complex Ru(bpy)2(OX)·4H2O has been synthesized. Its structure consists of a unique three-dimensional network in which Ru(bpy)2(OX)·4H2O units are alternatively linked by tetracyclic and octacyclic rings. The cyclic voltammogram of the titled compound has been studied. 相似文献
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Wen-Hao Chang Chia-Hsien Lin Ying-Jhe Fu Ta-Chun Lin Hsuan Lin Shuen-Jen Cheng Sheng-Di Lin Chien-Ping Lee 《Nanoscale research letters》2010,5(4):680-685
We report on the diamagnetic responses of different exciton complexes in single InAs/GaAs self-assembled quantum dots (QDs) and quantum rings (QRs). For QDs, the imbalanced magnetic responses of inter-particle Coulomb interactions play a crucial role in the diamagnetic shifts of excitons (X), biexcitons (XX), and positive trions (X−). For negative trions (X−) in QDs, anomalous magnetic responses are observed, which cannot be described by the conventional quadratic energy shift with the magnetic field. The anomalous behavior is attributed to the apparent change in the electron wave function extent after photon emission due to the strong Coulomb attraction by the hole in its initial state. In QRs, the diamagnetic responses of X and XX also show different behaviors. Unlike QDs, the diamagnetic shift of XX in QRs is considerably larger than that of X. The inherent structural asymmetry combined with the inter-particle Coulomb interactions makes the wave function distribution of XX very different from that of X in QRs. Our results suggest that the phase coherence of XX in QRs may survive from the wave function localization due to the structural asymmetry or imperfections. 相似文献
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An earlier proposed method for assessing the π-electron content (EC) of rings of heteroatom–containing polycyclic conjugated molecules [Balaban et al., Polycyclic Aromatic Compounds/27 (2007) 51] is modified so that the effects of heteroatoms become additive. By means of this, relatively simple rules for the changes of the EC-values could be formulated in the case of catafusenes. 相似文献