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81.
Jiang Zhao Meng Lian Yue Yu Xiaogang Yan Xianbin Xu Xiaolong Yang Guijiang Zhou Zhaoxin Wu 《Macromolecular rapid communications》2015,36(1):71-78
A series of novel red phosphorescent polymers is successfully developed through Suzuki cross‐coupling among ambipolar units, functionalized IrIII phosphorescent blocks, and fluorene‐based silane moieties. The photophysical and electrochemical investigations indicate not only highly efficient energy‐transfer from the organic segments to the phosphorescent units in the polymer backbone but also the ambipolar character of the copolymers. Benefiting from all these merits, the phosphorescent polymers can furnish organic light‐emitting diodes (OLEDs) with exceptional high electroluminescent (EL) efficiencies with a current efficiency (η L) of 8.31 cd A−1, external quantum efficiency (η ext) of 16.07%, and power efficiency (η P) of 2.95 lm W−1, representing the state‐of‐the‐art electroluminescent performances ever achieved by red phosphorescent polymers. This work here might represent a new pathway to design and synthesize highly efficient phosphorescent polymers.
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The effect of a thermal annealing treatment on the performance of bulk heterojunction photovoltaic cells based on poly[2-methoxy-5-(2′-ethyl-hexyloxy)-p-phenylene vinylene] (MEH-PPV) and fullerene (C60) composites is investigated. Upon thermal annealing at 120 °C, short-circuit current and power conversion efficiency (η) are more than tripled, while a sharp rise by eight times in and η is found for the device annealed at 200 °C. It is concluded that the improved phase separation between MEH-PPV and C60 leads to the enhancement of and η at 120 °C, while thermodynamic molecule arrangement at the higher temperature of ∼200 °C induces a significant increase in all photovoltaic parameters of composite devices except the open-circuit voltage . 相似文献
84.
This paper deals with the anti-synchronization problem of a class of delayed neural networks. Based on the Lyapunov stability theory and the Halanay inequality lemma, a kind of controller is designed. It is proved that this kind of controller can achieve anti-synchronization of neural networks with delays. Numerical simulations demonstrate the effectiveness and robustness of the proposed anti-synchronization scheme. 相似文献
85.
Yan Meng Ding Congcong Shu Xiaoyan Liu Yi Yang Jingjun Wei Guilin Zhang Zhentao Xie Yi Lu Xirui 《Journal of Radioanalytical and Nuclear Chemistry》2021,329(1):401-410
Journal of Radioanalytical and Nuclear Chemistry - To long-term immobilization of secondary iodine-waste, iodine loaded silver-coated silica-gel (AgIs), glass-powder was used to directly solidify... 相似文献
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88.
Theoretical studies of cobalt(I)‐catalyzed hydroacylation of vinylsilanes and alkyl aldehydes 下载免费PDF全文
Density functional theory (DFT) was used to investigate computationally cobalt(I)‐catalyzed hydroacylation of vinylsilanes and alkyl aldehydes to give ketones. Calculation indicated that cobalt(I)‐catalyzed hydroacylation had eight possible reaction pathways. In the cobalt‐hydride complexes IM2a and IM2b, the hydrogen migration occurred prior to the carbon–carbon bond‐forming reaction. In the complexes IM3a1 and IM3b1, the carbonyl elimination reaction occurred prior to the direct reductive elimination reaction. In the cobalt–carbonyl complexes IM4a and IM4b, the carbonyl insertion reaction was much easier to achieve than the decarbonylation reaction. The dominant reaction pathway was the reaction channel IM1a → TS1a → IM2a → TS2a1 → IM3a1 → TS4a → IM4a → TS5a → IM5a → TS6a → IM6a, and the reductive elimination reaction was the rate‐determining step for this channel, so the dominant product predicted theoretically was the linear ketone. Furthermore, the solvation effect was remarkable, and it decreased generally the free energies of the species. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
89.
Qin Meng Guo-Ming Wang Huan He Bai-Feng Yang Guo-Yu Yang 《Journal of Cluster Science》2014,25(5):1295-1305
Two new pentaborates [M(dap)3][B5O6(OH)4]2·H2O (M = Co (1) and Ni (2); dap = 1,2-diaminopropane) have been hydrothermally synthesized. Both structures were determined by single crystal X-ray diffraction and further characterized by elemental analysis, FT-IR, thermogravimetric analysis and photoluminescence spectroscopy. Two compounds are isostructural and consist of isolated pentaborate [B5O6(OH)4]? anions and [M(dap)3]2+ complex cations. The anionic [B5O6(OH)4]? groups are linked by extensive hydrogen bonds to form a 3-D supramolecular framework with large channels, in which the transition-metal complex templates are located. The luminescent properties of 1 and 2 were studied, and blue luminescence occurs with an emission maximum at 405 and 408 nm upon excitation at 332 and 328 nm respectively. Crystal data: 1, monoclinic, space group P21/c (No. 14), a = 9.7159(5) Å, b = 29.3372(19) Å, c = 11.5121(6) Å, β = 103.286(5)°, V = 3193.6(3) Å3, Z = 4; 2, monoclinic, space group P21/c, a = 9.7264(4) Å, b = 29.3810(16) Å, c = 11.5185(6) Å, β = 103.249(4)°, V = 3204.0(3) Å3, Z = 4. 相似文献
90.
Meng Li Hong‐Ye Bai Zu‐Lin Da Xu Yan Chao Chen Jin‐Hui Jiang Wei‐Qiang Fan Wei‐Dong Shi 《Crystal Research and Technology》2015,50(3):244-249
CaFe2O4/MgFe2O4 nanowires with heterostructure had been successfully synthesized by electrospinning method. The obtained samples were systematically characterized by scanning electron microscopy (SEM), X‐Ray diffraction (XRD), UV–Vis diffuse reflectance spectra (UV‐Vis DR) and Environment scanning electron microscopy (ESEM). The novel CaFe2O4/MgFe2O4 nanowires exhibit an enhanced photocatalytic activity for degrading of tetracycline (TC) under visible light. Compared with bare CaFe2O4 or MgFe2O4 samples, the prepared CaFe2O4/MgFe2O4 (Ca:Mg:Fe = 3:2:10) composited nanowires show the best photocatalytic performance with a degradation efficiency of 40% after 150 min reaction time. This enhancement is attributed to the heterostructure of CaFe2O4/MgFe2O4 nanowires, which effectively repress the recombination of photo‐generated electrons and holes. Based on heterostructure and energy band positions, the enhancement of mechanism under visible‐light enhances the photocatalytic activity. 相似文献