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91.
Dependence of Performance of Organic Light-emitting Devices on Sheet Resistance of Indium-tin-oxide Anodes 总被引:2,自引:0,他引:2
ZHOU Liang ZHANG Hong-jie YU Jiang-bo MENG Qing-guo PENG Chun-yun LIU Feng-yi DENG Rui-ping PENG Ze-ping LI Zhe-feng 《高等学校化学研究》2006,22(4):427-431
IntroductionIndium-tin-oxide(ITO) has been widely used asthe anode material in organic light-emitting devices(OLEDs) because of its high transmittance in the visi-ble region and low electrical resistivity. In the pastyears, many investigations focused on … 相似文献
92.
Vladislav?Tomi?i?Email author Vjekoslav?Butorac Jadranka?Viher Vladimir?Simeon 《Journal of solution chemistry》2005,34(6):613-616
The effect of temperature on the π∗←π transition band in the UV absorption spectrum of NO3−(aq) centered at ≈200 nm was studied in the temperature range 10–70 ∘C. The observed temperature independence of this band was in contrast to the significant influence of temperature on the nitrate π∗←n transition reported recently by us. However, taking into account the electronic states involved in both the transitions, it was concluded that this finding was in accordance with our previous assumption that interconversion between spectrally distinct (with respect to π∗←n band) nitrate species included the rupture/formation of hydrogen bond(s) in the hydration shell of the nitrate ion. 相似文献
93.
A continuous-wave 280 nm light-emitting diode (LED) was used as the excitation source for native fluorescence detection of proteins in CE. The operating current and temperature of the LED were optimized in order to achieve high luminescence power. It was found that a forward current of 30 mA and a temperature of approximately 5 degrees C gave the best S/N. By using a set of two ball lenses to focus light from the LED, we achieved a spot of approximately 200 mum with a power of 0.1-0.2 mW on the detection window. Fluorescence was collected with a ball lens at 90 degrees angle through a bandpass filter onto a photomultiplier tube. In CZE an LOD of 20 nM for conalbumin was reached. In capillary gel electrophoresis all eight proteins from a commercial standard kit were detected with high S/N. For a 10 microg/mL total protein mixture, S/N was better than 3 for all proteins in solution. Further improvement in LOD should be possible on utilization of an LED with higher luminescence power. 相似文献
94.
95.
Yue Shen Xiaohui Tang Yuwei Xu Haichao Liu Shitong Zhang Bing Yang Yuguang Ma 《中国化学快报》1990,30(11):1947-1950
Cyanophenyl as ancillary acceptor to modify donor-acceptor compound,plays an effective role in shifting the emission color to deep red and maintaining the luminescent efficiency. 相似文献
96.
97.
测定啤酒和白葡萄酒中有机酸的离子排斥色谱法 总被引:6,自引:0,他引:6
研究了离子排斥色谱法分离测定啤酒和白葡萄酒中有机酸;选用常见的盐酸溶液作淋洗液,以四丁基氢氧化铵为再生液,考察了淋洗液浓度、流量等因素对分离和测定的影响,对啤酒和白葡萄酒中常见有机酸在阴离子排斥色谱柱上的保留行为进行了系统的研究;通过试验确定最佳的色谱条件为盐酸浓度1.10mmol/L,流量0.80mL/min;四丁基氢氧化铵浓度5.0mmol/L,流量1.10mL/min;并在该条件下,测定了啤酒和白葡萄酒中的有机酸。 相似文献
98.
Summary A small cartridge containing a drying agent is inserted between a solid phase extraction (SPE) column and a gas chromatograph (GC) to enable the introduction of water-free desorption solvent into the GC in on-line liquid chromatography (LC)-type enrichment of trace-level analytes from water samples. Some characteristics of the drying agents, such as their capacity to retain water and their re-usability after heating, have been tested. Possible interactions of the drying agent with the analytes, e.g., irreversible adsorption or catalyzed degradation, have been checked for a wide range of alkanes, alkylbenzenes chlorobenzenes, chlorophenols and phthalate esters. Using the on-line SPE-GC system with flame ionization detection (FID) and spiked samples containing different levels of the test compounds, the repeatability was shown to be satisfactory (6–17%). For 10 mL samples, the detection limits were lower than 0.1 g/L. The on-line SPE-GC-FID system here presented can be used for the repeated analysis of water samples without exchange of the dyring cartridge. The technique is applied to the analysis of tap water. 相似文献
99.
采用索氏萃取法提取大气降尘中的有机物,用自制的硅胶层析柱进行了分离纯化,并以气相色谱/质谱法对提取物进行了分析.结果表明:从临沂师范学院前十学生公寓和临沂市汽车总站采集到的大气降尘样品中都含有较多的烷类、醛酮类、苯类和酯类有机化合物,并检测到一定量的卤代烃、酞酸酯类、多环芳烃类等有害于健康的物质.经初步推测,大气降尘中的有机化合物与机动车尾气排放有很大关系.文中对大气降尘中有机化合物的分析将为进一步研究大气降尘中有害物质的来源、迁移及其转化规律提供参考. 相似文献
100.
Single cell analytics for proteomic analysis is considered a key method in the framework of systems nanobiology which allows a novel proteomics without being subjected to ensemble-averaging, cell-cycle, or cell-population effects. We are currently developing a single cell analytical method for protein fingerprinting combining a structured microfluidic device with latest optical laser technology for single cell manipulation (trapping and steering), free-solution electrophoretical protein separation, and (label-free) protein detection. In this paper we report on first results of this novel analytical device focusing on three main issues. First, single biological cells were trapped, injected, steered, and deposited by means of optical tweezers in a poly(dimethylsiloxane) microfluidic device and consecutively lysed with SDS at a predefined position. Second, separation and detection of fluorescent dyes, amino acids, and proteins were achieved with LIF detection in the visible (VIS) (488 nm) as well as in the deep UV (266 nm) spectral range for label-free, native protein detection. Minute concentrations of 100 fM injected fluorescein could be detected in the VIS and a first protein separation and label-free detection could be achieved in the UV spectral range. Third, first analytical experiments with single Sf9 insect cells (Spodoptera frugiperda) in a tailored microfluidic device exhibiting distinct electropherograms of a green fluorescent protein-construct proved the validity of the concept. Thus, the presented microfluidic concept allows novel and fascinating single cell experiments for systems nanobiology in the future. 相似文献