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991.
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In this study, nano-scale honeycomb-shaped structures with anti-reflection properties were successfully formed on SiC. The
surface of 4H-SiC wafer after a conventional photolithography process was etched by inductively coupled plasma. We demonstrate
that the reflection characteristic of the fabricated photodiodes has significantly reduced by 55% compared with the reference
devices. As a result, the optical response I
illumination/I
dark of the 4H-SiC photodiodes were enhanced up to 178%, which can be ascribed primarily to the improved light trapping in the
proposed nano-scale texturing. 相似文献
995.
Poly(lactic acid) blends with desired end-use properties by addition of thermoplastic polyester elastomer and MDI 总被引:1,自引:0,他引:1
Haydar U. Zaman Jun Cheol Song Lee-Soon Park Inn-Kyu Kang Soo-Young Park Giseop Kwak Byung-sik Park Keun-Byoung Yoon 《Polymer Bulletin》2011,67(1):187-198
The disadvantages of the poor mechanical properties of polylactic acid (PLA) limit its ability to be used in a wide number of applications. Melt blending of PLA and thermoplastic polyester elastomer (TPEE) has been performed in an effort to toughen the PLA without significant losses in modulus and ultimate tensile strength. In order to enhance the compatibility of PLA and TPEE, a diisocyanate compound was used as a reactive modifier. The thermal and mechanical properties, miscibility and phase morphologies of the blends were investigated. A blend of PLA and TPEE with a modifier does not lead to an important drop in tensile strength and modulus whereas the elongation at break is characterized by a significant increase (above 300%), compared with that of neat PLA and PLA/TPEE. The blends of PLA/TPEE/Modifier were found by thermal and fractured surface analysis to be an immiscible system with the addition of a modifier. However, the relative ductility of PLA/TPEE/Modifier is 34 times higher than that of neat PLA. The brittle fracture of neat PLA was transformed into a ductile fracture by the addition of a modifier. 相似文献
996.
针对中石化某裂解装置的控制问题,通过实测模型,根据内模控制理论,提出一种二自由度的内模控制器的设计和参数整定方法.通过参数整定,所设计的控制器可以控制系统,同时具有良好的设定值跟踪特性和抑制干扰特性.将该二自由度控制器设计方法应用于蒸汽裂解装置中,减小了装置升温过程的波动,克服了保温过程的扰动,并且缩短了升温时间,提高... 相似文献
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998.
Suk-Hwan Kang Jae-Hong Ryu Jin-Ho Kim P. S. Sai Prasad Jong Wook Bae Joo-Young Cheon Ki-Won Jun 《Catalysis Letters》2011,141(10):1464-1471
Abstract
Fischer–Tropsch synthesis (FTS) reaction for the direct production of gasoline range hydrocarbons (C5–C9) from syngas was investigated on cobalt-based FTS catalyst supported on the ZSM-5 possessing a four different Si/Al ratio. The FTS catalysts were prepared by impregnation method using cobalt nitrate precursor in a slurry of ZSM-5, and they were characterized by surface area, XRD, H2-TPR and NH3-TPD. Cobalt supported catalyst on ZSM-5 having a low Si/Al ratio of 15 was found to be superior to the other catalysts in terms of better C5–C9 selectivity due to the formation of small cobalt particle and the presence of larger number of weak acidic sites. It also exhibited the highest catalytic activity because of the higher reducibility and the small cobalt particle size. 相似文献999.
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