Highly Efficient Simplified Organic Light-Emitting Diodes Utilizing F4-TCNQ as an Anode Buffer Layer

We demonstrate that the electroluminescent performances of organic light-emitting diodes （OLEDs） are significantly improved by evaporating a thin F4-TCNQ film as an anode buffer layer on the ITO anode. The optimum Alq3-based OLEDs with F4-TCNQ buffer layer exhibit a lower turn-on voltage of 2.6 V, a higher brightness of 39820cd/m^2 at 13 V, and a higher current efficiency of 5.96cd/A at 6 V, which are obviously superior to those of the conventional device （turn-on voltage of 4.1 V, brightness of 18230cd/m^2 at 13 V, and maximum current efficiency of 2.74calla at 10 V）. Furthermore, the buffered devices with F4-TCNQ as the buffer layer could not only increase the efficiency but also simplify the fabrication process compared with the p-doped devices in which F4-TCNQ is doped into β-NPB as p-HTL （3.11 cd/A at 7 V）. The reason why the current efficiency of the p-doped devices is lower than that of the buffered devices is analyzed based on the concept of doping, the measurement of absorption and photoluminescence spectra of the organic materials, and the current density-voltage characteristics of the corresponding hole-only devices.     

以BAlq为主体的高效高色纯度的红色有机电致磷光器件

以铱配合物红色磷光体Ir(piq)₂(acac)为掺杂剂,制备了基于BAlq材料的红色电致磷光器件,其结构为ITO/NPB(30nm)/Ir(piq)₂(acac):BAlq(25nm)/BCP(13nm)/Alq₃(35nm)/LiF(1nm)/Al(1000nm),当掺杂浓度为8%的时候,器件发光的色坐标为(x=0.67,y=0.32),基本满足了全色显示对红色发光的要求。在电压为16V时,器件达到最高亮度9380cd/m²。在电流密度为5.45mA/cm²时,外量子效率达到最大5.7%。由于磷光体Ir(piq)₂(acac)的磷光寿命较短,所以器件在高电流密度下,仍然保持较高的外量子效率。电流密度为100mA/cm²时,外量子效率仍然维持在4.7%。进一步研究表明在器件中短程的Dexter能量传递以及红光染料对空穴的直接捕获两种机制同时存在。     

湿蒸汽条件下空心静叶缝隙抽吸性能的试验研究

为获得湿蒸汽流动条件下空心静叶缝隙除湿结构的设计依据,利用湿蒸汽试验平台、在与实际空心静叶工作湿度一致的条件下,对8组不同缝隙位置、形状和宽度的空心静叶进行了缝隙抽吸水膜性能的试验研究。结果表明:缝隙抽吸水膜的特性受到气流马赫数和抽吸差压的综合作用,当抽吸差压增大到一定程度时,缝隙尖角处发生水膜汽化是导致抽吸性能下降的重要因素;吸力面缝隙位置从0.24倍叶宽变化到0.42倍叶宽时,缝隙抽吸的水量持续增加;与平直缝隙相比,带台阶过渡的缝隙抽吸性能未提高,反而在马赫数大于0.7时出现显著下降,原因是引起水膜汽化的尖角数目增加;带圆角过渡的缝隙能有效消除水膜汽化,提高缝隙抽吸水膜的性能;0.35mm宽度的缝隙易于使水膜跨过缝隙,2mm宽度的缝隙不能形成有效的抽吸差压,且均导致缝隙抽吸性能降低;0.7mm和1mm宽度的缝隙均具有良好的抽吸性能,1mm宽度的缝隙受水膜汽化的影响更小。     

低渗透油田氮气注入方案优化研究

针对低渗透区块裂缝发育、层间串较严重,层内及层间储量动用不均衡等情况。选择氮气驱并进行了方案优化,主要是从5个方面进行了方案的优化,包括注入氮气量优化、氮气注入速度优化、氮气注入周期优化、汽水比优化、注氮气前置段塞优化等,优化结果如下：氮气和水交替注入周期为4个月、气水比为1∶2、注气速度6000m3/d、注水量70m3/d、试验设计注入纯氮气段塞0.13PV。现场实践证明,注气后试验区日油略有上升,含水略有下降,初步取得了较好的增产效果。     

双组分道路交通标线研究进展

为了有效提高双组分道路交通标线的路用性能,促进双组分道路交通标线的推广应用,本文通过梳理国内外对双组分道路交通标线路用性能的最新研究成果,简要介绍了双组分道路交通标线材料体系及其固化原理,总结了道路标线耐久性的评价指标,并探讨了温度、雨水侵蚀、紫外辐射以及车辆磨耗等对其的耐久性的影响。同时,论述了面撒玻璃珠和发光材料对提升道路交通标线可视性的效果,结果表明,面撒密度范围9%~24%的高折射率玻璃珠和添加发光粉SrAl2O4:Eu²⁺,Dy³⁺对道路标线可视性提升效果最佳。此外,阐述了组成设计优化、纳米材料(纳米TiO2、纳米填料和纳米粘土)等方法改善道路交通标线的路用性能的方法,并在此基础上对未来的发展和研究方向进行了展望,以期推动双组分道路交通标线的发展,助力交通强国建设。     

燃气轮机双燃料喷嘴燃油内流场特性仿真分析

作为燃气轮机中的重要部件,喷嘴内部结构直接决定了燃油燃烧和动力输出效率,设计喷嘴结构并开展喷嘴中内流场特性仿真分析成为新型燃气轮机开发的研究重点。使用Solidworks软件对双燃料喷嘴结构进行设计,并对其燃油流道进行数值模拟。利用Fluent软件先对喷嘴燃油的整体内流场进行数值k-epsilon模拟,再使用流体容积法（VOF）方法对喷嘴燃油的核心流道进行数值模拟,研究喷嘴燃油流道的特性。结果显示燃油流道的质量流量、进口流速和核心流道进口流速随着进口压力的增大而增大;雾化锥角会随着进口压力的增加而增大,且当进口压力超过0.5 MPa时,雾化锥角最终会稳定在110°左右;同时结合相关实验数据与仿真数据进行对比。本文的仿真研究为燃气轮机喷嘴的结构改进提供了依据。     

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.     

Lowering the driving voltage and improving the luminance of blue fluorescent organic light-emitting devices by thermal annealing a hole injection layer of pentacene

We chose pentacene as a hole injection layer (HIL) to fabricate the high performance blue fluorescent organic light-emitting devices (OLEDs). We found that the carrier mobility of the pentacene thin films could be efficiently improved after a critical annealing at temperature 120 °C. Then we performed the tests of scanning electron microscopy, atomic force microscopy, and Kelvin probe to explore the effect of annealing on the pentacene films. The pentacene film exhibited a more crystalline form with better continuities and smoothness after annealing. The optimal device with 120 ℃ annealed pentacene film and n-doped electron transport layer (ETL) presents a low turn-on voltage of 2.6 V and a highest luminance of 134800 cd/m² at 12 V, which are reduced by 26% and improved by 50% compared with those of the control device.     

关于我校学生公寓党建工作的探索与思考

高校管理体制改革使公寓思想政治工作的重要性日渐突出,也给高校党建工作带来了新的挑战,文章探讨了如何开展公寓党建工作与二级学院党建工作有效的融合,充分发挥学生党员的模范带头作用,对创建和谐校园有着重要的意义。     

Effect of NaCl doped into Bphen layer on the performance of tandem organic light-emitting diodes

To improve the performance of tandem organic light-emitting diodes （OLEDs）, we study the novel NaCl as n-type dopant in Bphen：NaCl layer. By analyzing their relevant energy levels and cartier transporting characteristics, we discuss the mechanisms of the effective charge generation layer （CGL） of Bphen：NaCl （6 wt%）/MoO3. In addition, we use the Bphen：NaC1 （20 wt%） layer as the electron injection layer （ELL） combining the CGL to further improve the performance of tandem device. For this tandem device, the maximal current efficiency of 9.32 cd/A and the maximal power efficiency of 1.93 lm/W are obtained, which are enhanced approximately by 2.1 and 1.1 times compared with those of the single- emissive-unit device respectively. We attribute this improvement to the increase of electron injection ability by introducing of Bphen：NaCl layer. Moreover, the CGL is almost completely transparent in the visible light region, which is also important to achieve an efficient tandem OLEDs.