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981.
Laurent Rubaldo Alexandre Brunner Jocelyn Berthoz N. Péré-Laperne A. Kerlain P. Abraham D. Bauza G. Reimbold Olivier Gravrand 《Journal of Electronic Materials》2014,43(8):3065-3069
At high temperature, infra-red focal plane arrays are limited by their performance in operability, detectivity D * or noise equivalent temperature difference. Trap characterization and defect studies are necessary to better understand these limitations at high temperature. In this paper, we use deep level transient spectroscopy to study electrically active defects in mercury cadmium telluride n +/p diodes. The material investigated has a cut-off frequency (λ c) of 2.5 μm at 180 K and p doping performed with mercury vacancy. Trap energy signatures as well as capture cross-section measurements are detailed. A low temperature hole trap close to midgap is observed in the range 150–200 K with an activation energy around 0.18 ± 0.025 eV. A high temperature hole trap is also observed in the range 240–300 K with an activation energy of 0.68 ± 0.06 eV. A hole capture cross-section of 10?19 cm2 is obtained for both traps. The nature of the defects and their correlation with dark current are discussed. 相似文献
982.
Camille Leroux Alexandre J. Raymond Gabi Sarkis Ido Tal Alexander Vardy Warren J. Gross 《Journal of Signal Processing Systems》2012,69(3):305-315
The recently-discovered polar codes are seen as a major breakthrough in coding theory; they provably achieve the theoretical capacity of discrete memoryless channels using the low-complexity successive cancellation decoding algorithm. Motivated by recent developments in polar coding theory, we propose a family of efficient hardware implementations for successive cancellation (SC) polar decoders. We show that such decoders can be implemented with O(N) processing elements and O(N) memory elements. Furthermore, we show that SC decoding can be implemented in the logarithmic domain, thereby eliminating costly multiplication and division operations, and reducing the complexity of each processing element greatly. We also present a detailed architecture for an SC decoder and provide logic synthesis results confirming the linear complexity growth of the decoder as the code length increases. 相似文献
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Alexandre Descomps 《合成通讯》2014,44(6):757-761
The unstable ketones 1-bromo-3-buten-2-one, 1-bromo-3-butyn-2-one, and 1,3-dibromo-3-buten-2-one can be obtained from the corresponding acetals in high yields by treating the acetals with anhydrous iron (III) chloride suspended on dry silica. A simplified procedure for preparing the reagent is also given. 相似文献
987.
Maria V. Ivanova Dr. Alexandre Bayle Dr. Tatiana Besset Prof. Dr. Xavier Pannecoucke Dr. Thomas Poisson 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(30):10284-10293
The difluoromethyl phosphonate motif plays a crucial role in the development of bioactive molecules as it is considered as a phosphate bioisoster. Since 2010, a renewal of interest to enlarge the panel of reactions to access these difluoromethylated phosphonate‐containing molecules has been witnessed. This Concept article charts the recent progress that has been made. 相似文献
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