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331.
A novel partial silicon on insulator high voltage LDMOS with low-k dielectric buried layer 下载免费PDF全文
A novel partial silicon-on-insulator (PSOI) high voltage device with a low-k (relative permittivity) dielectric buried layer (LK PSOI) and its breakdown mechanism are presented and investigated by MEDICI.At a low k value the electric field strength in the dielectric buried layer (E I) is enhanced and a Si window makes the substrate share the vertical drop,resulting in a high vertical breakdown voltage;in the lateral direction,a high electric field peak is introduced at the Si window,which modulates the electric field distribution in the SOI layer;consequently,a high breakdown voltage (BV) is obtained.The values of EI and BV of LK PSOI with kI=2 on a 2 μm thick SOI layer over 1 μm thick buried layer are enhanced by 74% and 19%,respectively,compared with those of the conventional PSOI.Furthermore,the Si window also alleviates the self-heating effect. 相似文献
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333.
Claudia Valentina Popa Liliana Lungu Ligia Florentina Cristache Crinu Ciuculescu Andrei Florin Danet 《Natural product research》2015,29(18):1744-1747
To gain new insight into the antimicrobial potential of Ailanthus altissima Swingle, ethanol leaf extracts were evaluated for the antifungal effects against the model yeast Saccharomyces cerevisae. The extracts inhibited the yeast growth in a dose-dependent manner, and this effect could be augmented by heat shock, exposure to visible light or exposure to high concentrations of Ca2+. Using transgenic yeast cells expressing the Ca2+-dependent photoprotein, aequorin, it was found that the leaf extracts induced cytosolic Ca2+ elevation. Experiments on yeast mutants with defects in Ca2+ transport demonstrated that the cytotoxicity of the A. altissima leaf extracts (AaLEs) was mediated by transient pulses of Ca2+ ions which were released into the cytosol predominantly from the vacuole. The investigation of the antifungal synergies involving AaLEs may contribute to the development of optimal and safe combination therapies for the treatment of drug-resistant fungal infections. 相似文献
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