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PVK与新型D-π-A分子掺杂体系的能量转移及发光性质 总被引:1,自引:0,他引:1
通过对PVK与4种新型D-π-A分子(分别简写为CKD, TKD, PKD, NKD)掺杂体系的吸收光谱、激发光谱和光致发光光谱的研究, 分析了掺杂体系的光致发光特性和能量转移现象. 制备了结构为ITO/PEDOT/PVK∶D-π-A ω/Alq3/Al的电致发光器件, 研究了掺杂体系的电致发光性能. 研究结果表明, 通过改变D-π-A分子中不同给电子能力的电子给体, 可以调控其带隙, 进而实现对D-π-A分子发光峰位的调节; 给电子基团空间立构效应越高, 其荧光量子效率越高. 在掺杂体系的光致发光和电致发光中, PVK与D-π-A分子之间都发生了有效的能量转移, 通过调节PVK与D-π-A分子的比例, 可以调节掺杂体系的发光性能. 当TKD在PVK中的掺杂质量分数为6%时, 电致发光器件发光亮度为729.1 cd/m2时, 发光效率达到1.75 cd/A. 相似文献
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The formation of mono-atomic tantalum(Ta)metallic glass(MG)through ultrafast liquid cooling is investigated by ab-initio molecular dynamics(MD)simulations.It is found that there exists nearly golden ratio order(NGRO)between the nearest and second nearest atoms in Ta MG,which has been indirectly confirmed by Khmich et al.and Liang et al..The NGRO is another universal structural feature in metallic glass besides the local five-fold symmetry(LFFS).Further analyzing of electronic structure shows that the obvious orientation of covalent bond could be attributed to the NGRO in amorphous Ta at 300 K. 相似文献
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Simulation study on the formation and transition properties of cluster structures in liquid metals during rapid cooling processes 总被引:3,自引:0,他引:3
For the first time, a molecular dynamics simulation study has been performed for a liquid metal system consisting of 50000 atoms to deeply investigate the transitions of microstructure configurations dudng the rapid cooling processes. Especially, the cluster-type index method has been adopted to analyze the transforming and evolving processes of clusters and cluster configurations from liquid metal atoms. It has been found that the bigger cluster configurations in the system are formed by means of connecting some small clusters (they are combined by several smaller clusters), and not taken on the multi-shells configuration accumulated with an atom as the center and the surrounding atoms arranged according to some fixed pattern. With the decrease in temperature, the probability of repetitive appearance for clusters increases largely, which reveals that clusters are indeed possessing a certain relative stability and continuity (namely hereditary effect). These results will give us an important enlightenment to understand not only the forming mechanisms and microscopic processes of the short-order sections and disorder sparse sections in amorphous structures but also the freezing processes of liquid metals.`` 相似文献
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采用基于NEB的MEP的LST/QST方法, 发展了一种不依赖团簇初始结构而得到其低能稳态构型的过渡态搜索方法, 预测和分析了孤立与铰链双二十面体Agn (n=13, 19, 23, 24, 25)的低能稳态构型. 证实Ag13-Ih的低能稳态构型是一个含有五角双锥碎片的Ag13-C2扁平层状结构, 而Ag19-D5h的低能稳态构型则是在13原子二十面体上添加6原子组成Ag19-C1球形结构. 并且揭示Ag23-D3h, Ag24-D2h, Ag25-D5d与Agn (n=17~22)团簇一样, 其低能稳态构型也含有一个13原子的变形二十面体核心. 相似文献