Highly efficient polymer phosphorescent light-emitting devices based on a new polyfluorene derivative as host

Several highly efficient iridium-complex polymer light-emitting devices (PLEDs) are fabricated,with a newly synthesized blue conjugated polymer,poly[(9,9-bis(4-(2-ethylhexyloxy)phenyl)-fluorene)-co-(3,7-dibenziothiene-S,S-dioxide15)] (PPF-3,7SO15),chosen as host.High luminous efficiencies of 7.4 cd·A 1 and 27.4 cd·A 1 are achieved in red and green PLEDs,respectively,by optimizing the doping concentrations of red phosphorescent dye iridium bis(1-phenylisoquinoline) (acetylacetonate) (Ir(piq)) and green phosphorescent dye iridium tris(2-(4-tolyl)pyridinato-N,C 2) (Ir(mppy) 3).Furthermore,highly efficient white PLEDs (WPLEDs) with the Commission Internationale de l’Eclairage (CIE) coordinates of (0.35,0.38) are successfully produced by carefully controlling the doping concentration of the irid-ium complex.The obtained WPLEDs show maximal efficiencies of 14.4 cd·A 1 and 10.1 lm·W 1,which are comparable to those of incandescent bulbs.Moreover,the electroluminescent spectrum of the white device with an initial luminance of about 1000 cd·m 2 is stable,subject to constant applied current stress,indicating that good device stability can be obtained in this system.     

光学仿真设计实践能力培养训练的思考与探索

教学团队本着"重理论建模、强仿真设计、突创新实践、促科学探索"的教育理念,依托"数学物理方法与仿真"和"空间光通信创新实验"两门课程,重点开展了小班教学大学生光学仿真设计实践能力培养训练的思考与探索,通过近几年的教学研究与实践,其构建的光学仿真设计"阶梯次"能力训练教学实践培养模式,对培养大学生具有"宽泛的专业知识、科学的探索能力、仿真设计能力强和综合素质能力高"的创新型设计人才具有突出教学效果.     

Effects of mask-alignment error on point spread function for multi-level Fresnel diffractive lenses

The full aperture complex amplitude transmittance function of a multi-level diffraction lens with maskalignment errors was derived based on scalar diffraction theory. The point spread function(PSF) was calculated by the Kirchhoff diffraction integral. It is found that the radius of the Airy disk increases with the increase of the error in the direction of misalignment, and the image center shifts along the direction of misalignment. A fourlevel diffractive lens with a diameter of 80 mm was fabricated, and its PSF and diffraction efficiency of +1 st order were calculated and measured. The distribution of PSF is consistent with the calculated results, and the tested diffraction efficiency is slightly smaller than the calculated value; the relative error is 5.71%.     

手性希夫碱的合成及其催化不对称硅氢插入反应的研究

合成了结构中同时含有氮和磷的新型手性希夫碱,将希夫碱与金属配合物结合催化α-苯基-α-重氮乙酸甲酯与硅氢化合物的不对称硅氢插入反应,考察了不同的金属铜配合物和希夫碱对反应的影响,探讨了手性希夫碱／金属配合物催化体系对不同硅氢底物的适应性．当采用希夫碱4与Cu（CH3CN）4PF6的催化体系催化α-苯基-α-重氮乙酸甲酯与二甲基苯基硅烷的不对称硅氢插入反应时,反应具有优良的产率（100％）和对映选择性（76％）．     

SnS2纳米片/氧化石墨烯复合材料的制备及其光催化性能研究

为探讨SnS2纳米片/氧化石墨烯(GO)复合材料的光催化活性,采用液相氧化法制备GO,通过一步水热合成法,控制GO的含量和反应时间制备了一系列SnS2/GO复合材料.采用XRD,DRS,TEM,IR表征了制得的催化剂,研究了催化剂在可见光(λ ＞420 nm)下降解甲基橙的催化性能.结果表明:改变GO含量,SnS2六边形结构保持不变,SnS2/GO复合材料比纯的SnS2具有更高的光催化活性.当GO与SnS2质量比为5％,反应36 h催化效果较佳.     

物性参数对封闭腔体自然对流数值模拟的影响

采用两种不同的物性参数处理方法对不同温差下的封闭方腔内自然对流进行数值计算,研究瑞利数Ra从103～106之间时,封闭方腔内空气的流动换热规律,将所得到的数值模拟结果与研究文献做了对比分析,验证了其方法的准确性,同时对比分析了利用多项式考虑气体物性参数随温度变化情况下的数值模拟结果.计算结果表明,在所计算的问题中,小温差下把热物性参数设置为常数可以一定程度上减小计算量,加快计算收敛速度,但在大温差下,物性参数设置为常数计算将造成计算结果相对误差较大.     

大都市边缘区高标准基本农田潜力评价及建设模式研究——以重庆市渝北区为例

研究目的:以研究区土地利用动态度与耕地和基本农田现状分析为先导,通过大都市边缘区高标准基本农田潜力评价体系构建和潜力结果分析,总结了大都市边缘区高标准基本农田建设模式与建议;研究方法:GIS分析法、土地利用动态度分析法和多目标综合评价法;研究结果:研究区基本农田分值大于60的高标准基本农田总面积为4 355.27hm2,主要集中分布在茨竹镇、兴隆镇、大湾镇和大盛镇共10个片区;研究结论:构建了城郊农业生产主导型、景观生态农业主导型、生态阻隔功能主导型三种大都市边缘区高标准基本农田建设模式.     

混凝土裂缝的成因与处理

本文对荷载导致的裂缝、温度导致的裂缝、收缩引起的裂缝、地基变形引起的裂缝、钢筋锈蚀引起的裂缝、施工材料质量引起的裂缝、施工工艺质量引起的裂缝等混凝土裂缝的产生原因进行了分析,并对各种裂缝的预防和处理进行了介绍。     

Sol-gel preparation of a silica enhanced hydrophobicity and antireflective coating with optical stability in vacuum

A new silica antireflective coating with improved hydrophobicity and optical stability in a vacuum is obtained by a two-step route. Firstly, silica sols are prepared with a sol-gel process, in which tetraethyl orthosilicate is utilized as a precursor. And by introduction of fluorine containing glycol into the sols, the porosity of silica particles and surface polarity of the coatings are decreased. Afterward, coatings are constructed with low surface roughness by modification of PMBA-PMMA. The coatings retain transmission of up to 99.6%, and laser damage threshold of about 50 J/cm^2 at a wavelenth of 532 nm （1-on-1. 10 ns）     

BTT导弹基于扩张状态观测器的滑模控制律设计

针对BTT导弹非线性动力学模型中的参数不确定性及系统存在未知外部干扰的问题,提出了一种基于扩张状态观测器的滑模控制设计方法;将系统参数不确定性和未知外界干扰作为系统的复合干扰,采用扩张状态观测器估计系统的复合干扰,并实时补偿;利用Lyapunov方法证明系统的稳定性;该控制器算法简单、计算量小,更易于实际工程应用;仿真结果表明,设计的控制器对导弹控制系统受到的复合干扰具有较强的鲁棒性和稳定性,满足导弹姿态快速机动和高稳定度的控制要求,性能指标明显优于滑模控制器。