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Three types of blue-violet light-emitting devices based on an exciton-confined structure have been prepared, in which different materials were used as emitting layers and hole-transporting layers. They had structures of ITO/CuPc/NPB/CPB/TPBi/Alq3/LiF/Al(DNC), ITO/CuPc/JO3/CBP/TPBi/Alq3/LiF/Al(DJC ) and ITO/CuPc/JO3/FNPD/TPBi/Alq3/LiF/Al(DJF). Here copper phthalocyanine (CuPc) acted as hole-injecting layer( HIL), N, N-bis-(1-naphthyl)-N, N-diphenyl-1. lbiphenyl-4-4-diamine(NPB) and J03 bole-transporting layers ( HTLs), 4,4‘-dicarbazolyl-1,1‘ -biphenyl (CBP) and FNPD as emitting layers( EMLs), N, arylbenzimidazoles (TPBi) as holeblocking layer ( HBL ), and tris(8-quinolinolato ) aluminium complex ( Alq3 ) as electron- transporting layer ( ETL). TPBi applied here is a good confinement to both charges and excitons, which make the devices emit blue-violet light originating from the emitter, CBP and FNPD. Their characteristics have also been investigated. The result shows that the device DNC based on NPB/CBP has the best performance among the three devices. The excellence of DNC is attributed to the better hole-transporting ability of NPB as compared with J03, and the better emitting ability of CBP as compared with FNPD, although the best matching of energy levels is found in the hole-transporting layer and emitting layer of the device DJP. 相似文献
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目的：探讨癌基因C-erbB-2在周围型肺癌发生、发展中的作用。方法：采用免疫组化和流式细胞术、聚合酶链反应三种方法检测基因表达是否一致及与生物学行为、CT征象的关系。结果：癌基因C-erbB-2蛋白表达与患者的年龄、性别、TNM分期无关，在肺腺癌中的表达明显高于鳞癌（P（0．05），肺癌的分化程度低、有肺门或纵隔淋巴结转移C-erbB-2蛋白表达明显增高（P〈O．05）。C-erbB-2蛋白表达与深分叶征、棘突征有关；而与肿瘤的大小、短细毛刺征、胸膜凹陷征无关。三种方法检测C-erbB-2蛋白及mRNA表达水平一致．结论：癌基因C-erbB-2在肺癌发生、发展、CT征象中起重要作用，检测这种基因并结合CT征象可作为临床诊断及评估预后的有效指标。 相似文献
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A new blue electroluminescent material,distyrylarylene(DSA)derivative,4,4‘-bis[2,2-(1-naphthyl,phenyl)vinyl]-1,1-biphenyl(NPVBi)is designed and synthesized.The DSA derivative shows better thermal stability because of its high glass transition temperature.A blue organic light emitting diode(OLED0with the structure ITO/TPD/NPVBi/Alq/LiF/Al is studied.The electroluminescent(EL0spectrum of the OLED exhibits that light emission originates from NPVBi with a peak at 460nm,its Commission Internationale de l‘Eclairage(CIE)color coordinates are x=0.16,y=0.15,and showing independence of CIE color coordinates on current density.The new DSA derivative is expectable as a new candidate for blue light emitter in OLEDs. 相似文献
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目的:通过研究肾脏结核在CT、IVP两种影像中的表现与病理所见的关系,来揭示肾结核的影像学表现在二种检查方法之间的互补性,以期达到早发现、早确诊、早治疗的目的.方法:搜集130例经病理证实为肾结核的病例,回顾性总结,对CT平扫及增强、IVP二种检查方法进行比较.结果:CT诊断符合率93.0%,不能明确诊断7%,IVP诊断符合率36.6%,未能明确诊断63.4%.结论:CT能清楚显示整个肾脏的横断面图像,对肾实质及肾盂、肾盏的形态结构均显示清楚,且有很高的密度分辨率,对空洞及肾内钙化的检出率明显高于平片及肾盂造影.增强扫描及延迟扫描可以用于肾功能的判断、与肾盂旁囊肿、肾盂肿瘤的鉴别.所以肾结核的诊断,CT明显优于肾盂造影. 相似文献
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笔者在北京出版物发行业状况调查时发现,我国现行的渠道模式过于散滥,行业集中度低,扛鼎流通渠道具有强大控制力的"三流合一"发行中盘还未建立起来.出版物流通渠道困境的形成是众多因素复杂运动的结果,是出版上游的狂发滥铺与中下游流通渠道的无序销货共同导致了出版发行流通秩序的混乱. 相似文献
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因果过度决定是困扰着因果反事实理论的一个难题。通过澄清该难题的含义，陈述细粒度策略解决方案以及刘易斯对此方案的反驳，然后借助对思维经济原则的分析，指出因果过度决定难题导源于对思维经济性的过分追求，进而引出认知层次问题。认知层次的确定应以所需解决的问题为导向，而不存在绝对的统一标准，人类认知也无须这样的标准。对因果过度决定难题典型案例的分析表明，虽然理性分析策略似乎可解决砸碎玻璃瓶之类的难题，但因忽视人脑的计算消耗而无法分析认知层次问题。比较而言，资源理性分析策略基于计算时间来测算大脑的计算消耗，从而约束一分到底的分层倾向，注重计算代价与认知效用之间的动态平衡，乃是优于简单理性分析策略的方案。 相似文献
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