Improved performance of organic light-emitting diodes with dual electron transporting layers

In this study the performance of organic light-emitting diodes(OLEDs) are enhanced significantly,which is based on dual electron transporting layers(Bphen/CuPc).By adjusting the thicknesses of Bphen and CuPc,the maximal luminescence,the maximal current efficiency,and the maximal power efficiency of the device reach 17570 cd/m2 at 11 V,and 5.39 cd/A and 3.39 lm/W at 3.37 mA/cm2 respectively,which are enhanced approximately by 33.4%,39.3%,and 68.9%,respectively,compared with those of the device using Bphen only for an electron transporting layer.These results may provide some valuable references for improving the electron injection and the transportation of OLED.     

苯海拉明的拉曼光谱和红外光谱研究

测量并分析了盐酸苯海拉明的红外光谱和拉曼光谱。在Raman光谱中, 1001 cm-1出现一个极强峰, 在1030 cm-1和618 cm-1各有一个中等峰,此外,在红外光谱中, 714 cm-1和757 cm-1附近出现极强的吸收峰,认定这个化合物中存在单取代苯。C-N的对称伸缩振动出现在837 cm-1, 1433 cm-1和1470 cm-1分别为CH2和CH3的变形振动, 在红外光谱中, 1020 cm-1处明显的吸收峰属于C-O-C反对称伸缩振动。此外, 测量得到含量为25 mg苯海拉明药片的拉曼光谱与纯苯海拉明的拉曼峰比较一致, 可作为无损快速检测该药物的手段。     

一种宽能谱多球中子谱仪能量响应的MC模拟

利用蒙特卡罗程序FLUKA模拟计算了聚乙烯慢化球和辅助材料慢化球对低能中子到高能中子的响应函数曲线。结果表明,对纯聚乙烯球来说,随着聚乙烯层厚度的增加,响应曲线峰逐步右移,峰值在高能区有所下降,对20 Me V以上的中子,无论纯聚乙烯球的尺寸有多大,其响应均下降到很低的程度;对辅助材料慢化球来说,中子能量小于1 Me V时,辅助材料慢化球与聚乙烯慢化球的响应曲线相似,但当中子能量大于20 Me V时,中子与辅助材料层发生(n,xn)反应,慢化球的响应呈显著上升趋势。分析计算结果,最终能够确定宽能谱多球中子谱仪的尺寸组合。     

The system design and assemble for the high resolution telescope system with segmented aperture

A design method along with its results, for a space optical system with high resolution and wide field of view, is described. Such optical systems can be used in the infrared as well as visible configurations. The proposed design is based on an on-axis Ritchey-Chrétien system with corrected lens element while the primary mirror is a segmented aperture. Here the on-axis concept allows wide-field enabling a variety of observations designed for the multi-object spectrometer instruments, optimized for low scattering and low emission of light. The use of segmented mirrors in the optical system allows adopting any method for its fabrication purposes. Segment results are discussed and the image quality of the design based on these results is evaluated in this paper.     

基于伪态协议的量子密钥分配系统研究

采用包含两个伪态和一个信号态的双伪态协议分析了量子密钥分配系统的性能,比较了双伪态（真空态—弱伪态）和单伪态协议条件下密钥生成率与通信距离的关系,分析了信号态的强度、量子比特误码率、单光子的增益和单光子的误码率对系统密钥生成率的影响,得出密钥生成率的最优化条件,为实现实用安全的量子密钥分配系统奠定理论基础. 关键词： 伪态协议 量子密钥生成率 量子比特误码率     

Geometric Phase in a Generalized Jaynes-Cummings Model with Double Mode Operators and Phase Operators

By using of the invariant theory, we have studied the geometric phase of quantum dots in the time-dependent isotropic magnetic field, the dynamical and geometric phases are given, respectively.     

Efficient one-pot synthesis of Ag nanoparticles loaded on N-doped multiphase TiO2 hollow nanorod arrays with enhanced photocatalytic activity

The simultaneous Ag loaded and N-doped TiO₂ hollow nanorod arrays with various contents of silver (Ag/N-THNAs) were successfully synthesized on glass substrates by one-pot liquid phase deposition (LPD) method using ZnO nanorod arrays as template. The catalysts were characterized by Raman spectrum, field-emission scanning electron microscopy (FESEM), high-resolution transmission electron microscope (HRTEM), ultraviolet-vis (UV-vis) absorption spectrum and X-ray photoelectron spectroscopy (XPS). The results suggest that AgNO₃ additive in the precursor solutions not only can promote the anatase-to-rutile phase transition, but also influence the amount of N doping in the samples. The photocatalytic activity of all the samples was evaluated by photodegradation of methylene blue (MB) in aqueous solution. The sample exhibited the highest photocatalytic activity under UV light illumination when the AgNO₃ concentration in the precursor solution was 0.03 M, due to Ag nanoparticles acting as electron sinks; When the AgNO₃ concentration was 0.07 M, the sample performed best under visible light illumination, attributed to the synergetic effects of Ag loading, N doping, and the multiphase structure (anatase/rutile).     

The dislocations in graphene with the correction from lattice effect

The dislocation widths and Peierls stresses of glide dislocations and shuffle dislocations in graphene have been studied by the improved Peierls-Nabarro (P-N) equation which contains the discrete correction. The discrete parameter is obtained from a simple dynamic model in which the interaction attributed to the variation of bond length and angle was considered. The restoring force in the improved P-N equation is given by the gradient of the generalized stacking fault energy surface (γ-surface). Our calculation shows that the widths of the shuffle dislocation and the glide dislocation are narrow and the width of the shuffle dislocation is about twice wider than the glide dislocation. The Peierls stress of a shuffle dislocation is one order of magnitude smaller than that of a glide dislocation. As a consequence, the shuffle dislocation moves more easily than the glide dislocation.     

Vacancy defects in delafossite СuАlO<Subscript>2</Subscript>: First-principles calculations

Electronic properties and formation energies of vacancy defects in delafossite CuAlO₂ have been investigated by using the first-principles density functional theory. The band structures and density of states of various vacancy defects have been obtained and analyzed. The results show that the V _Cu systems with different charge states influence the type of conductivity. The introduced vacancy defects enhance the hybridization between O-2p and Cu-3d states, which is good for p-type conductivity. The calculated formation energies indicate that the Cu vacancy is relatively easy to form and it trends to have positive charge.