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101.
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Reagen Ying‐Tai Su Li‐Ko Chiu Shan‐Wei Weng Ying‐Shiun Chou Raymond Chien‐Chao Tsiang 《Journal of Polymer Science.Polymer Physics》2012,50(4):280-288
White polymeric light‐emitting diode (WPLED) based on a single polymer, poly(3‐hexylthiophene‐alt‐9,9‐dioctylfluorene) (PTAF), has been successfully demonstrated. This conjugated alternating copolymer, PTAF, comprises 50 mol % of 3‐hexylthiophene which is an orange‐red color chromophore and 50 mol % 9,9‐dioctylfluorene which is a bluish‐green color chromophore. It was synthesized by Suzuki cross‐coupling reaction and has a molecular weight of 15,021 and polydispersity of 1.36. Nanocomposite consisting PTAF and graphene nanosheets enhances the optoelectronic properties and the device fabricated with a configuration of ITO/PEDOT:PSS/(PTAF + 1% graphene)/Ca/Al shows two‐color white electroluminescence with CIE 1931 coordinates of (0.28, 0.34). The white luminescence from a single polymer affords the WPLED device a simple structure and low fabrication cost. © 2011 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2011 相似文献
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Zhixin Wang Yujie Cai Xiangru Liao Feng Zhang Dabing Zhang Zhiling Li 《Applied biochemistry and biotechnology》2010,162(1):280-294
A new white-rot fungus SYBC-L1, which could produce an extracellular laccase, was isolated from a decayed Elaeocarpus sylvestris. The strain was identified as Pycnoporus sp. SYBC-L1 according to the morphological characteristics and ribosomal ITS1-5.8S-ITS2 RNA genomic sequence analysis. The
highest laccase activity of 24.1 U ml−1, which was approximately 40-fold than that in basal medium, was achieved in optimal culture medium in submerged fermentation.
The laccase produced by Pycnoporus sp. SYBC-L1 was not only a cold adaptation enzyme with a relative catalytic activity of 30.2% at 0°C but also a high thermostable
enzyme. The half-lives at 60, 70 and 80°C were 85.5, 37.2, and 2.6 h, respectively. The laccase could effectively decolorize
weak acid blue AS and diamond black PV up to 88% and 74.7%, respectively, within 2 h in the absence of any redox mediators.
The results suggested Pycnoporus sp. SYBC-L1 was a potential candidate for laccase production and industrial application. 相似文献
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Sodium borohydride regioselectively reduced various 3-sulfonyl glutarimides 1 to hydroxy piperidones 2, which were further dehydrated to 3,4-dihydro-5-sulfonylpyridin-2-ones 3 in the presence of boron trifluoride. Formal synthesis of 8a-epi-dendroprimine (4) possessing an indolizidine ring system has been accomplished via intramolecular radical cyclization of cyclic vinyl sulfone 5. 相似文献
109.
We derive the spin-wave dynamics of a magnetic material from the time-dependent spin-density-functional theory in the linear response regime. The equation of motion for the magnetization includes, besides the static spin stiffness, a "Berry curvature" correction and a damping term. A gradient expansion scheme based on the homogeneous spin-polarized electron gas is proposed for the latter two quantities, and the first few coefficients of the expansion are calculated to second order in the Coulomb interaction. 相似文献
110.