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41.
A simple method for solving the Fredholm singular integro-differential equations with Cauchy kernel is proposed based on a new reproducing kernel space. Using a transformation and modifying the traditional reproducing kernel method, the singular term is removed and the analytical representation of the exact solution is obtained in the form of series in the new reproducing kernel space. The advantage of the approach lies in the fact that, on the one hand, by improving the definition of traditional inner product, the representation of new reproducing kernel function becomes simple and requirement for image space of operator is weakened comparing with traditional reproducing kernel method; on the other hand, the approximate solution and its derivatives converge uniformly to the exact solution and its derivatives. Some examples are displayed to demonstrate the validity and applicability of the proposed method. 相似文献
42.
A novel 3D star-shaped acceptor based on triphenylamine as a core and diketopyrrolopyrrole as arms (S(TPA-DPP)) was synthesized. S(TPA-DPP) exhibited excellent thermal stability, strong absorption, and very high open-circuit voltage (1.18 V) in solution-processed organic solar cells based on P3HT:S(TPA-DPP). 相似文献
43.
Huo L Huang Y Fan B Guo X Jing Y Zhang M Li Y Hou J 《Chemical communications (Cambridge, England)》2012,48(27):3318-3320
A new building block of benzo[1,2-b:4,5-b']difuran (BDF) was firstly designed and synthesized. The newly designed unit was applied for constructing a new photovoltaic low band gap polymer, PBDFDTBT, which exhibited promising power conversion efficiency of 5.0%. 相似文献
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导电高聚物修饰纳米尺度TiO~2多孔膜电极的光电化学研究 总被引:21,自引:1,他引:20
用光电化学方法研究了用导电高聚物修饰的纳米晶TiO~2多孔膜电极在不含氧化还原对和含不同氧化还原对体系电解质溶液中的光电转换过程。TiO~2/导电高聚物多孔膜电极为双层n型半导体结构,内层TiO~2多孔膜的禁带宽度为3.26eV,外层聚吡咯(PPy)膜的禁带宽度为2.23eV,而聚苯胺(PAn)膜的禁带宽度为2.88eV。用导电高聚物修饰半导体电极能使其在可见光区的光吸收增加,光电流增强,且起始波长红移至>600nm,使宽禁带半导体电极的光电转换效率得到明显改善。 相似文献
46.
嵌入电极反应的循环伏安图一般具有氧化峰和还原峰间距很大的特点,并且往往要求采用非常低的电位扫描速度。本研究基于嵌入电极反应的热力学方程和电荷传递动力学方程,对其循环伏安曲线进行了理论处理,讨论了嵌入电极反应热力学参数b,动力学参数D和k,电位扫描速度u,及电极和溶液电阻对循环伏安曲线的影响,解释了实验得到的嵌入电极反应循环伏安曲线的特殊性。 相似文献
47.
集值映射图的广义相依导数与真有效解的最优性条件 总被引:1,自引:0,他引:1
本文提出了集值映射图的SP-相依导数的概念,利用这个概念,给出了集值向量优化问题两种真有效解的最优性条件. 相似文献
48.
Prof. Junghoon Lee So‐Huei Kang Sang Myeon Lee Dr. Kyu Cheol Lee Heesoo Yang Yongjoon Cho Daehee Han Prof. Yongfang Li Prof. Byoung Hoon Lee Prof. Changduk Yang 《Angewandte Chemie (International ed. in English)》2018,57(41):13629-13634
To understand the effects rendered on the relevant basic physical properties and device function by controlling the regiochemistry of the cyclopenta[1,2‐b:5,4‐b′]dithiophene‐fluorobenzo[c][1,2,5]thiadiazole polymer (hereafter referred to as the CDT‐FBT polymer), two polymers, the regiorandom polymer (RA) and regioregular version (RR), respectively, are synthesized and characterized. In addition, an efficient route for synthesizing a key monomer for RR using various synthesis scope and optimizing the reaction conditions is discussed. Although RA exhibits optical, electrochemical, and morphological properties similar to RR, it shows better field‐effect transistor (FET) performance. Surprisingly, by employing a capillarity‐mediated sandwich‐casting process on a nanogrooved substrate, an unprecedented mobility of 17.8 cm2 V?1 s?1 is obtained for RA‐based FETs; this mobility value is almost twofold greater than those of the corresponding RR‐based FETs. For the first time, this study challenges previously reported results in that high carrier mobility is related to the high degree of polymer order induced by the backbone regioregularity. 相似文献
49.
Haiyan?Jia Qingyun?Tian Jingkun?XuEmail author Limin?LuEmail author Xue?Ma Yongfang?Yu 《Mikrochimica acta》2018,185(11):517
A three-dimensional porous network graphene aerogel (GAs) with large specific area and excellent conductivity was loaded with β-cyclodextrin polymer (Pβ-CD) to serve as a support for immobilization of antibodies. A highly sensitive immunosensor for the cancer marker carbohydrate antigen 15–3 (CA15–3) was designed based on the use of Pβ-CD/GAs. The large specific area of GAs warrants high loading with antibodies, and their excellent electrical conductivity warrants strong electrical signals. Based on the synergistic effect of GAs and Pβ-CD, an immunoassay was designed that is making use of hexacyanoferrate as an electrochemical probe and having a pleasantly low working potential of 0.2 V (vs. SCE). Response is linear in the 0.1 mU mL?1 to 100 U mL?1 activity range, and the lower detection limit is 0.03 mU mL?1 (at S/N =?3). The immunoassay is stable, selective and reproducible. It was applied to the analysis of spiked samples, and results were satisfactory. 相似文献
50.