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71.
72.
By p-doping buckminsterfullerene (C60) into a bipolar host 2,7-bis(diphenylphos-phorryl)-9-[4-(N,N-dipheny-lamino)phenyl]-9-phenylfluorene, the device efficiency of the phosphorescent homojunction organic light-emitting device (HJOLED) was pronouncedly enhanced. A two-fold enhancement in luminous efficacy compared with nondoped or MoO3 doped HJOLEDs was observed by employing C60 as the p-dopant. The influence of C60 doping on the device performances of this HJOLED was investigated by carefully analyzing the J-V-L characteristics of HJOLEDs with different hole transporting layer. A white HJOLED was also successfully fabricated. The maximum brightness, current efficiency and power efficiency were 22700 cd m?2, 12.2 cd A?1 and 7.7 lm W, respectively. This device showed a warm EL spectra and the CIE coordinates was (0.41, 0.44) @ 10 V. Besides, this device manifested lower efficiency roll-off.  相似文献   
73.
优化模式物理参数的扩展四维变分同化方法   总被引:1,自引:0,他引:1       下载免费PDF全文
王云峰  顾成明  张晓辉  王雨顺  韩月琪  王耘锋 《物理学报》2014,63(24):240202-240202
数值模拟的一个重要误差来源是模式物理参数,为提高模拟准确率,如何改进模式物理参数是亟需解决的问题.本文对经典四维变分同化技术进行了改进,提出了一种新的利用观测资料来同时优化模式初始场和物理参数的扩展四维变分同化方法,并以Ekman边界层模式和Lorenz模式为例进行了数值试验.结果表明,利用本文提出的新方法,通过对观测资料的变分同化,可以在实现对模式初始场进行优化的同时,纠正了模式物理参数中的误差,从而有效提高了模式的模拟准确率.该方法对于改进数值模式物理参数有着重要的促进意义.  相似文献   
74.
Cheng-Ming Chu 《Tetrahedron》2007,63(8):1863-1871
A mild and efficient process for the 1,4-addition of thiols and benzeneselenols to various α,β-unsaturated ketones using a catalytic amount of CAN with excellent product yields is described. This inexpensive, nontoxic, and readily available catalytic ceric(IV) ammonium nitrate system efficiently catalyzes conjugate addition reactions between thiol derivatives and various α,β-unsaturated ketones under solvent-free conditions. A plausible mechanism for the role of CAN, both as a promoter in free radical chain addition reactions as well as a catalyst for the conjugate addition process is proposed.  相似文献   
75.
The preparation and infrared spectroscopic studies of coordination compounds of salicylaldoxime, 2-hydroxy-acetophenone oxime, 2-hydroxy-benzophenone oxime and 2-hydroxy-4-methoxy-benzophenone oxime with copper (II), nickel (II), cobalt (II) and iron (II) are described. The frequency of the C=N stretching vibration is usually higher in the complex than that in the ligand. The higher this frequency is, the larger the stability constant of the complex will be, but there is no quantitative relationship. In the case of complexes of salicylaldoxime with Cu (II), Ni (II), Co (II) and Fe (II), vO=N values are correlated linearly with the ionization potentials of the central metal ions. The frequency of the OH stretching vibration is closely related to the geometric configuration of the complex. Thus aromatic hydroxyoximes form coordination compounds with Co (II) and Fe (II) with cis configuration possessing six-membered hydrogen-bonded ring. This is indicated in the infrared spectra by the complete absence of the OH stretching band, or by the appearance of an extremely broad and flat band of very low intensity. However, Cu (II) or Ni (II) complex possesses trans configuration with five-membered hydrogen-bonded bridge showing characteristic OH absorption band in the infrared region. The voh's of complexes investigated are closely related to the polar nature of substituents on the benzene ring. By examining the spectra of 63Cu and 65Cu complexes with 2-hydroxy-4(5)-substituted benzophenone oximes in the far infrared region, the characteristic frequency of M-O and M-N were assigned for a series of aromatic hydroxyoxime-transition metal complexes.  相似文献   
76.
张新军  秦成明  赵燕平 《中国物理》2005,14(11):2251-2255
This paper considers the coupling analysis of phased antenna array designed to excite fast wave in the ion cyclotron range of frequency. The coupling of the antenna is calculated in slab geometry. The coupling code based on the variational principle gives the self-consistent current flowing in the antenna, this method has been extended so that it can be applied to a phased antenna array. As an example, this paper analyses the coupling prosperities of a 2 × 2 phased antenna array. It gives the optimum geometry of antenna array. The fields excited at plasma surface are found to more or less correspond to the antenna current phasing.  相似文献   
77.
The 1,4-addition of various thiols to α,β-unsaturated ketones was completed rapidly in the presence of a catalytic amount (2-3 mol %) of anhydrous iron(III) chloride under solvent free conditions and an air atmosphere. Anhydrous iron(III) chloride is more active than that of other ferric salts. With more reactive and/or less steric reagents (1a-c and/or 2a-2c), expeditious conditions (short reaction times at room temperature) could be employed. With less reactive and/or steric reagents (1d-g and/or 2d-e), a slight increase in reaction time was required, but high yields were obtained. The FeCl3 catalyst causes preferential interactions with α,β-unsaturated ketones present in the reaction.  相似文献   
78.
深空背景下空间目标红外特性建模方法研究   总被引:2,自引:0,他引:2       下载免费PDF全文
孙成明  袁艳  张修宝 《物理学报》2010,59(10):7523-7530
针对空间目标红外特性提出了一种精确建模方法.根据空间目标的背景辐射环境,充分考虑到目标表面间的热传导及内热源的影响,建立了空间目标的热平衡方程.基于目标的结构特性和材料特性,利用节点网络法求解了目标表面的温度分布.根据光辐射定律、光散射定律建立了空间目标红外特性的数学模型.结合具体的参数,对深空目标资源一号卫星和风云三号卫星的温度场分布和辐照度分布进行了数值计算,仿真结果验证了理论分析的正确性.  相似文献   
79.
光抽运垂直扩展腔面发射激光器腔内倍频理论研究   总被引:1,自引:0,他引:1       下载免费PDF全文
建立了计入光波在非线性晶体中走离和相位失配情况下的光泵面发射激光器腔内倍频的速率方程理论模型,采用循环数值逼近的方法对该速率方程进行求解.以BBO,LBO,PPLN等非线性晶体为例,研究了晶体长度以及抽运功率等因素对倍频输出功率的影响,模拟结果与实验结果符合得较好. 关键词: 光抽运 垂直扩展腔面发射激光器 腔内倍频 数值模拟  相似文献   
80.
芳香族羟肟类化合物能与过渡金属离子螯合,已成功地应用于金属分析和湿法冶金。显然,此类配合物结构和键性质的研究对于了解反应机理和配位体的分子设计具有指导意义,已经开展了多方面的研究。作者曾报道了2-羟基-4(5)-取代二苯甲酮肟顺式(Syn)和反式(Anti)异构体的v_(OH)吸收红外光谱特性和  相似文献   
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