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排序方式: 共有105条查询结果,搜索用时 15 毫秒
1.
测定了一组八烷氧基萘酞菁镍(Ⅱ)配合物Ni(Ⅱ)(RO)8NPC(R=C4H9,C8H17,C12H25,NPC=C48H16N8)在5种有机溶剂(Py、DMSO、DMF、CH2Cl2、C6H12)中的电子吸收光谱和荧光光谱,研究了这些配合物的结构与光谱的关系。结果表明该系列RO取代萘酞菁镍(Ⅱ)配合物的Q带吸收光谱比无取代的红移75nm左右,荧光光谱屯相应红移50~80nm,而溶剂对其影响不大。  相似文献   
2.
High performance pentacene organic thin film transistors (OTFT) were designed and fabricated using SiO2 deposited by electron beam evaporation as gate dielectric material. Pentacene thin films were prepared on glass substrate with S--D electrode pattern made from ITO by means of thermal evaporation through self-organized process. The threshold voltage VTH was --2.75± 0.1V in 0---50V range, and that subthreshold slopes were 0.42± 0.05V/dec. The field-effect mobility (μEF) of OTFT device increased with the increase of VDS, but the μEF of OTFT device increased and then decreased with increased VGS when VDS was kept constant. When VDS was --50V, on/off current ratio was 0.48× 105 and subthreshold slope was 0.44V/dec. The μEF was 1.10cm2/(V.s), threshold voltage was --2.71V for the OTFT device.  相似文献   
3.
Organic light-emitting diode (OLED) based on two kinds of blue emission materials N,N′-bis(1-naphthyl)-N,N′-diphenyl-l,l′-diphenyl-4,4′-diamine (NPB) and 2-(4-biphenylyl)-5(4-tert-butyl-phenyl)-1,3,4-oxadiazole (PBD) was fabricated. There is only one emission peak in photoluminescence (PL) spectrum which originates from NPB exciton emission. And the electroluminescence (EL) emission peaks have an apparent red-shift with the increase of driving voltage. The red-shift emission from exciplex emission could be ruled out. Thus, by the method of Gaussian fitting it should be ascribed to the overlap of exciton emission and electroplex emission which occurs at the interface between NPB and PBD. The formation of the electroplex emission under high electric field is analyzed.  相似文献   
4.
吡喃并[4,3-b]吡喃衍生物与牛血清白蛋白作用的荧光光谱   总被引:1,自引:0,他引:1  
用荧光光谱法分析了在生理条件下一种吡喃并[4,3-b]吡喃衍生物—2-氨基-7-甲基-4-(4-硝基苯)-5-氧代-4H,5H-吡喃并[4,3-b]吡喃-3-腈与牛血清白蛋白的作用机制。求得不同温度下二者的结合常数和结合位点数,探讨了微量金属离子对实验体系结合常数的影响,并根据热力学参数确定了这种吡喃并[4,3-b]吡喃衍生物与牛血清白蛋白之间的作用力类型。根据Frster非辐射能量转移机理,测定了这种吡喃并[4,3-b]吡喃衍生物与牛血清白蛋白相互结合时,能量给体-受体间的作用距离和能量转移效率,并用同步和三维荧光技术讨论了其衍生物对牛血清白蛋白构象的影响。结果表明,吡喃并[4,3-b]吡喃衍生物主要以静态猝灭方式使牛血清白蛋白荧光强度显著降低,二者主要凭借氢键和范德华力结合。  相似文献   
5.
利用混蒸的方法、将空穴阻挡材料2,9-Dimethyl-4,7-diphenyl-1,10-phenanhroline及电子传输材料Tris(8-hydroxy-quinolinato)aluminium混合,在电子传输层及空穴阻挡层之间制备了薄层的混合界面.在相同驱动电压下,采用混合界面的器件比常规器件的电流密度和亮...  相似文献   
6.
将一种新型稀土铕配合物Eu(UVA)3 Phen作为掺杂剂与基质PVK按不同质量比进行掺杂,对混合薄膜的光致发光(PL)和电致发光(EL)特性进行了研究.实验结果表明,共掺杂体系中存在从PVK到Eu(UVA)3 Phen的F(o)rster能量传递.通过优化主客体材料的配比浓度,当掺杂浓度为4%时,得到了色纯度较好地红...  相似文献   
7.
Ring inversion of eight substituted 2-phenyl-4, 4-dimethyloxazolidines in o-dichlorobenzene-d4 was studied by 1H DNMR. Very high inversion barriers (ΔGo = 86.7–93.4 kJ·mol?1) were found for these oxazolidine rings. The magnitude of the inversion barrier is dependent on the polarity of the substituent on the phenyl group. A linear correlation is present between the ΔGo of the inversion and the substituent constant, σ+, of the substituent.  相似文献   
8.
频率啁啾激光场中锂原子的激发与态囚禁   总被引:1,自引:1,他引:0  
采用含时多态展开方法,对不同频率啁啾激光场中里德堡锂原子布居数的相干迁移特性进行了计算研究。结果表明:布居数跃迁几率对激光脉冲形状、激光场强度、啁啾率等参数非常敏感,在合适的激光参数下,可以实现布居数在四个量子态之间的完全迁移和量子态的囚禁。  相似文献   
9.
Tb3+-doped Ca2BO3C1 compounds with different charge compensation approaches are synthesized by a hightemperature solid-state reaction method, and the luminescent properties and Commission Internationale de l'Eclairage (CIE) chromaticity coordinates are systematically characterized. Ca2BO3Cl:Tb3+ can produce green emission under 376 nm radiation excitation. With codoped A+ (A = Li, Na, K) as charge compensators, the relative emission intensities of Ca2BO3Cl:Tb3+ are enhanced by about 1.61, 1.97, and 1.81 times compared with those of the direct charge balance, which is considered to be due to the effect of the difference in ion radius on the crystal field. The CIE chromaticity coordinates of Ca2BO3CI:Tb3+, A+ (A = Li, Na, K) are (0.335, 0.584), (0.335, 0.585), and (0.335, 0.585), corresponding to the hues of green. Therefore, A+ (A = Li, Na, K) may be the optimal charge compensator for Ca2BO3Cl:Tb3+.  相似文献   
10.
通过扫描电镜和X射线衍射对SiO2衬底上生长并五苯和酞菁铜薄膜的表面形貌进行表征,并得到在SiO2衬底上生长的并五苯薄膜是以岛状结构生长,其大小约为100nm,且薄膜有较好的结晶取向,呈多晶态存在. 酞菁铜薄膜则没有表现出明显的生长机理,其呈非晶态存在. 还对通过掩膜的方法制作得以酞菁铜和并五苯为有源层的顶栅极有机薄膜晶体管的特性进行了研究. 有源层的厚度为40nm,绝缘层SiO2的厚度为250nm,器件的沟道宽长比(W/关键词: 有机薄膜晶体管 并五苯薄膜 酞菁铜薄膜 μEF)')" href="#">场效应迁移率(μEF)  相似文献   
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