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1.
Electroluminescence of a Multi-Layered Organic Light-Emitting Diode Utilizing Trans-4-[p-[N-methyl-N-(hydroxymethyl)amino]styryl]-N-Methylphridinium Tetraphenylborate as the Active Layer
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Employing an organic dye salt of trans-4-[p-[N-methyl-N-(hydroxymethyl)amino]styryl]-N-methylphridinium tetra\-phenylborate (ASPT) as the active layer, 8-hydrocyquinoline aluminium (Alq3) as the electron transporting layer and N,N’-diphenyl-N,N’-bis(3-methylphenyl)-[1,1’-biphenyl]-4,4’-diamine (TPD) as the hole transporting layer, respectively, we fabricate a multi-layered organic light-emitting diode and observe the colour tunable electroluminescence (EL). The dependence of the EL spectra on the applied voltage is investigated in detail, and the recombination mechanism is discussed by considering the variation of the hole-electron recombination region. 相似文献
2.
盐酸异丙肾上腺素在伯瑞坦-罗比森缓冲溶液(pH=6.80)介质中有很强的荧光。其最大激发波长和发射波长为287nm和622nm。荧光强度与纯盐酸异丙肾上腺素浓度在0.1—2.3mg/L范围内呈线性关系。回归方程F=351.91C(mg/L) 139.02,r=0.9995,检出限为0.0087mg/L。测定注射用针剂中盐酸异丙肾上腺素的含量,方法简单,快捷,灵敏度高,结果令人满意。 相似文献
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热敏电阻温度计的设计与制作 总被引:2,自引:0,他引:2
本文介绍了设计性实验“热敏电阻的设计与制作”的实施情况。说明了只要选题合适、要求恰当,设计性实验不仅可行,而且对物理实验训练的总结提高十分有效。 相似文献
6.
To identify and eliminate the inner filter effects (IFEs), prepositive and side cells containing absorbents are fixed beside
the fluorescer contained cell. In this way, excitation and emission lights can be quenched by primary and secondary outer
filter effects respectively, depending on absorbent concentration and cell length. Herein the quenching of emission fluorescence
caused by IFEs can be equally reduced by outer filter effects (OFEs) and the interference of IFEs was eliminated. This approach
was experimentally used for identifying the interaction mode and mechanism between BSA and nanoAg. Results showed that the
quenching of BSA fluorescence and synchronous fluorescence mainly attributes to IFEs, instead of static/dynamic fluorescent
quenching. In view of the above, the elimination of the interference of IFEs by the design of OFEs plays an important part
in the precise application of fluorescence detector. 相似文献
7.
Three-dimensional (3D) laser carving is a new, very flexible process and is very useful for machining the hard and/or brittle materials such as ceramics, carbide and hardened steel with high precision, excellent productivity and surface quality. In this paper, the effects of laser processing parameters on single-layer carving depth and surface quality are analyzed by laser carving on an Al2O3 ceramic with different processing parameters. The mechanisms of laser carving are also studied. A mathematical model of the relationship between the laser processing parameters and the laser carving depth is established, which is useful in obtaining the best machining parameters with the shortest time. Finally, a 3D pattern is successfully carved using the optimum parameters. 相似文献
8.
This paper reports the photoluminescence (PL) properties of nanocrystalline CaZrO3:Tm phosphor synthesized by the polymerizable complex method based on the Pechini-type reaction. Nanosized phosphors with paving stone morphology were prepared at a relatively low temperature about 800 °C with the particle size being about 30 nm. The transmission electron microscope (TEM) images showed that further heat treatment at higher temperature could increase the particle size to 50 nm, but its morphology remained unchanged. The luminescence spectra indicated that the blue emission of CaZrO3:Tm could be produced by four kinds of excitation energies, i.e. the charge transfer (CTS) between Tm3+-O2−, band-band absorption of host, the absorption defects in the host and the 3H6-1D2 transition. The luminescent mechanism of CaZrO3:Tm was deduced tentatively based on the luminescence spectra. 相似文献
9.
QIAOYong-Fen LIRen-Jie MAYong-Sheng 《理论物理通讯》2004,42(6):801-804
Using the Lie Symmetry under infinitesimal transformations in which the time is not variable, the nonNoether conserved quantity of nonholonomic system having variable mass and unilateral constraints is studied. The differential equations of motion of the system are given. The determining equations of Lie symmetrical transformations of the system under infinitesimal transformations are constructed. The Hojman‘s conservation theorem of the system is established. Finally, we give an example to illustrate the application of the result. 相似文献
10.
Phase structures of immiscible polypropylene (PP)/polystyrene (PS) blends with different volume proportions, PP90/PS10, PP80/PS20, PP70/PS30, PP60/PS40, PP50/PS50, PP40/PS60, PP30/PS70, PP20/PS80, PP10/PS90, were observed by means of scanning electronic microscopy (SEM). The zero shear viscosities of the blends were determined according to a modified Carreau model by fitting the curves of static shear rate sweeps of blends tested at 190°C in a Stress Tech Fluids Rheometer. The results showed that the compositional dependence of zero shear viscosity of PP/PS deviated greatly from linear or log‐linear additivity. When PS was dispersed in a PP continuous phase, the blends showed negative deviation, while for blends with PP dispersed in a PS matrix, positive deviation was generated. When different theoretical equations of Nielsen, Utracki, Taylor, Frankel‐Acrivos (FA), Choi‐Schowalter (CS), and Han‐King (HK) were used to fit the experimental data of zero shear viscosities of blends, none of them was suitable for PP/PS blends. These experimental phenomena may result from the complex phase structures of the blends and their response to shear conditions, which are discussed in detail and compared with the experimental analysis. 相似文献