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891.
空气稳定的氮杂蔻电子传输材料分子设计及三氮杂蔻衍生物迁移率计算 总被引:1,自引:0,他引:1
采用密度泛函理论研究氮功能化对蒄类化合物几何构型、电子结构及载流子传输性质的影响. 结果表明, 引入杂N原子可以线性降低前线轨道能级, 增强电子注入能力与空气稳定性, 且邻位掺杂较迫位和均匀掺杂调节效果更为显著. 其中, 十二氮杂蒄(12ac)具有新颖的“碗状”构型和高的电子亲和势(3.45 eV), 是潜在的空气稳定电子传输材料构筑单元. 理论预测室温下2,6,10-三对甲氧基苯基-3,4,7,8,11,12-六甲氧基三氮杂蒄(3b)晶体的电子迁移率为0.242 cm2/V s, 预计是良好的电子传输材料, 值得进一步器件化研究. 相似文献
892.
用同轴静电纺丝制备了含有稀土铕配合物(Eu(TTA)3AA)的芯-壳结构的丁腈橡胶/聚乙烯吡咯烷酮(NBR/PVP)超细荧光纤维。考察了在外层PVP纺丝参数不变的情况下,改变芯层丁腈橡胶纺丝液的纺丝速度、Eu(TTA)3AA含量等对纤维形貌的影响。通过研究Eu(TTA)3AA-NBR/PVP同轴超细纤维中Eu(TTA)3AA微观结构、含量与纤维的荧光性能之间的关系,发现在同轴纤维形成过程中由于溶剂的快速挥发可使Eu(TTA)3AA形成无定形结构,进而在纤维中形成分子簇级别的分散,在Eu(TTA)3AA含量为30%时,同轴纤维比Eu(TTA)3AA粉末的荧光强度提高了2倍。 相似文献
893.
本文综述了有机杂化锑基主族异金属硫属化物的研究进展, 对它们的结构和异金属次级结构基元进行了描述、归类和总结;探讨了有机组分分别作为结构导向剂和配体两种角色所起到的不同作用;介绍了这类化合物在离子交换、光催化性能方面的研究;展望了该体系的发展趋势。 相似文献
894.
Narinder Singh 《Supramolecular chemistry》2013,25(5):351-357
A series of new p-tert-butylcalix[4]arene-based dipodal receptors are synthesised in high yields. The calix[4]arene units of all the receptors have been found to be present in cone conformation. To optimise the good extraction ability and high transport rate, we synthesised the receptors that differ from each other in their end groups. These receptors extract Cu2+ ion selectively from the buffered aqueous medium containing a mixture of metal ions. The receptor bearing four sp3 nitrogens has by far the greater ability to extract Cu2+ than the other receptors. All these receptors were effectively used for Cu2+ ion transport from the aqueous buffered source phase to the aqueous receiving phase. 相似文献
895.
Xuezhe Zhao Shengwei Deng Yongmin Huang Honglai Liu Ying Hu 《Frontiers of Chemistry in China》2011,6(3):159-163
The wrinkling of phase-separated binary polymer blend film was studied through combining the Monte Carlo (MC) simulation for
morphologies with the lattice spring model (LSM) for mechanical properties. The information of morphology and structure obtained
by use of MC simulation is input to the LSM composed of a three-dimensional network of springs, which allows us to determine
the wrinkling and the mechanical properties of polymer blend film, such as strain, stress, and Young’s modulus. The simulated
results show that the wrinkling of phase-separated binary polymer blend film is related not only to the structure of morphology,
but also to the disparity in elastic moduli between polymers of blend. Our simulation results provide fundamental insight
into the relationship between morphology, wrinkling, and mechanical properties for phase-separated polymer blend films and
can yield guidelines for formulating blends with the desired mechanical behavior. The wrinkling results also reveal that the
stretching of the phase-separated film can form the micro-template, which has a wide application prospect. 相似文献
896.
897.
An efficiently halogen-free flame-retardant long-glass-fiber-reinforced polypropylene system 总被引:4,自引:0,他引:4
Yun LiuCheng-Liang Deng Jing ZhaoJun-Sheng Wang Li ChenYu-Zhong Wang 《Polymer Degradation and Stability》2011,96(3):363-370
In order to solve the “candlewick effect” caused by glass fibers, which results in the decrease of flame retardancy of flame-retardant long-glass-fiber-reinforced polypropylene (LGFPP) systems, and the deterioration of mechanical properties caused by adding an additional amount of flame retardants compared with flame-retardant non-glass-fiber-reinforced polypropylene systems so as to keep a same flame retardancy, a novel intumescent flame retardant (IFR) system, which is composed of a charring agent (CA), ammonium polyphosphate (APP) and organically-modified montmorillonite (OMMT), was used to flame retard LGFPP. The thermal stability, combustion behavior, char formation, flame retardant mechanism and mechanical properties of the IFR-LGFPP samples were investigated by thermogravimetric analysis (TGA), limiting oxygen index (LOI), UL-94 test, cone calorimeter test, scanning electronic microscopy, and mechanical property tests. When the content of IFR is 20 wt%, the LOI value of IFR-LGFPP reaches 31.3, and the vertical burning test reaches UL-94 V-0 rating, solving the “candlewick effect” caused by long glass fiber without additional amount of the IFR. All the relevant cone calorimeter parameters also show that IFR-LGFPP has much better flame-retardant behaviors than LGFPP. Furthermore, the mechanical properties of IFR-LGFPP almost remain unchanged in comparison with those of LGFPP containing no IFR. The flame retardant mechanism was also discussed. 相似文献
898.
899.
900.
Jie-Hui Yu Ling-Yun Pan Tie-Gang Wang Xiao-Bing Cui Yi-Zhi Li Tian-Hui Ma 《Journal of solid state chemistry》2003,175(2):152-158
The title compound [NiII(phen)3]2[Cu10H2I16] 1 (phen=1,10-phenanthroline, C12H8N2) was hydrothermally synthesized from a simple reaction of CuI-NiCl2·6H2O-phen·H2O-H2O. X-ray analysis revealed that it consists of NiN62+ core cation and decanuclear iodocuprate(I) anion together with two dissociative H+ ions. In anionic unit, the discrete decanuclear iodocuprate(I) is formed by crystallographically independent five monovalent copper atoms and eight iodine atoms via an inversion center. There exist two types of Cu(I) coordination sites; only one copper(I) atom is in a highly distorted triangular planar site, and the other four copper(I) atoms display the tetrahedral geometries. It deserves to be noted that four types of bridging modes of I− ions in which two are ordinary μ2- and μ3-bonding modes can be found. But the other two are the rectangle planar geometry and the novel μ4-bridge like an “umbrella”, and both of them are rather rare in the halocuprates(I). Compound 1 was crystallized in triclinic space group with a=11.6861(17), b=14.590(2), c=14.649(2) Å, α=76.370(2), β=70.830(2), γ=81.320(3)o, R=0.075, and was characterized by elemental analysis, IR spectrum and UV-VIS spectrum. The third-order non-linear optical property of 1 was also investigated and the compound exhibits the reverse saturable absorption and self-defocusing performance. 相似文献