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991.
YU Jun-sheng SUO Fan LI Lu WANG Tao LI Wei-zhi JIANG Ya-dong 《光电子快报》2007,3(6):428-431
Blue and green organic light-emitting devices with a structure of indium tin oxide (ITO) /N,N’-bis-(1-naphthyl)-N,N’- diphenyl-1,1’-biphenyl-4,4’-diamine (NPB)/aluminum(III) bis(2-methyl-8-quinolinato)4 –phenylphenolato (BAlq) /tris(8- hydroxyquinolate)-aluminum (Alq3)/Mg:Ag have been fabricated. Blue to green light emission has been achieved with the change of organic film thickness. Based on energy band diagram and charge carrier tunneling theory, it is concluded that the films of different thicknesses play a role as a color-tuning layer and the color-variable electroluminescence (EL) is ascribed to the modulation function within the charge carrier recombination zone. In the case of heterostructure devices with high performance, the observed EL spectra varies significantly with the thickness of organic films, which is resulted from the shift of recombination region site. It has not been hitherto indicated that the devices compose of identical components could be implemented to realize different color emission by changing the film thickness of functional layers. 相似文献
992.
Tao Y Chen D Wei H Yuanhu P Liu Z Huang L Wang Y Xie S Yuan Z 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2012,29(5):736-745
A rapid method using accelerated solvent extraction (ASE) and ultrasound enhanced derivatisation has been developed for the quantitative determination of metabolites of nitrofurans, namely 3-amino-2-oxalidinone (AOZ), 5-morpholinomethyl-3-amino-2-oxalidinone (AMOZ), 1-amino-hydantoin (AHD) and semicarbazide (SEM), in muscle and skin of carp and finless eel. The target analytes were extracted using ASE, ultrasonic derivatisation for 1?h and then purified by solid phase extraction. Averaged decision limits (CCα) and detection capability (CCβ) of the method were in the range of 0.07-0.13 and 0.31-0.49?μg?kg?1 in carp and finless eel, respectively. The accuracy in terms of recovery was in the range 77.2-97.4%. The simplified and traditional methods were compared with incurred residue samples. The simplified method reduced the derivatisation time and has been applied to the determination of nitrofurans residues in fish. 相似文献
993.
饮用水中镉污染的应急处理技术中试研究 总被引:3,自引:0,他引:3
以模拟遭受突发性镉污染的水体为研究对象,在水厂常规工艺的基础上,考察了化学沉淀技术对镉污染原水的应急处理效果.结果表明,当分别采用三氯化铁和聚合氯化铝为混凝剂时,分别将滤后水pH值控制在8.69和8.58以上,可有效去除超标50倍的镉污染物,且对镉的去除率随着pH值的提高而增大;在最大应急能力方面,将滤后水pH值分别控制在9.17和8.73以上,可分别有效去除超标500和80倍的镉污染物,使镉浓度降至国标限值以下.在混凝前pH值变化不大的情况下,投加聚合氯化铝的滤后水pH值的降低幅度要大于投加三氯化铁的. 相似文献
994.
995.
Xianyu Liu Huijun Ge Shiwei Ma Shangyi Yin Ping Lu Laihong Shen Hongcun Bai Wei Wang Tao Song 《中国化学工程学报》1982,28(9):2417-2424
Efficiently using petroleum coke as fuel and reducing carbon emission meanwhile have become attractive in oil processing industry. The paper is focused on the application of Chemical Looping Combustion (CLC) with petroleum coke, with the purpose of investigating its combustion performance and effects of potassium. Some experiments were performed in a laboratory scale fluidized bed facility with a natural manganese-based oxygen carrier. Experimental results indicated that the coke conversion is very sensitive to reaction temperature. The present natural manganese-based oxygen carrier decorated by K has little effect on the improvement of coke conversion. XRD, SEM-EDX, and H2-TPR were adopted to characterize the reacted oxygen carrier samples. After being decorated by K, the oxygen carrier's capacity of transferring oxygen was decreased. A calcination temperature above the melting point of K2CO3 (891 °C) shows better oxygen transfer reactivity in comparison to the one calcined at a lower temperature. The natural oxygen carrier used in the work has a high content of Si, which can easily react with K to form K(FeSi2O6). Further, irrespective of reaction temperature, the coke conversion can be significantly enhanced by decorating the coke with K, with a demonstration of remarkably shorter reaction time, faster average coke gasification rate and higher average carbon conversion rate. 相似文献
996.
Longtao ZHANG Bo JIANG Wanmeng MU Tao ZHANG 《Frontiers of Chemical Science and Engineering》2009,3(4):393
D-psicose exits in an extremely small amount in nature and is difficult to be chemically synthesized. Only three bacteria have been used in the biotransformation of D-psicose from D-fructose. In this paper, another bacterium which could convert D-fructose to D-psicose was isolated and identified as Rhodobacter sphaeroides. The process parameters of D-psicose production using permeabilized cells of Rhodobacter sphaeroides SK011 were optimized, including the permeabilization procedure: 0.1% (w/v) CTAB, 10min, and reaction conditions: cell concentration, 30g dry cell wt/L; concentration of substrate, 50g/L; 40°C, pH 9.0; reaction time, 8 h. Under the optimized conditions, the permeabilized cells produced approximately 6.5g/L D-psicose with a D-psicose productivity of 0.82g·L−1·h−1. This is the first report of bioproduction of D-psicose using permeabilized cells of Rhodobacter sphaeroides. 相似文献
997.
ZHOU Jun CHU Wei ZHANG Hui XU Huiyuan ZHANG Tao 《Frontiers of Chemical Science and Engineering》2008,2(3):315
The effect of Fe content on FeMn/MgO catalysts for light alkenes synthesis through CO hydrogenation was investigated. Catalysts were prepared by a conventional co-impregnation method, characterized using BET, X-ray powder diffraction (XRD) and Temperature-programmed reduction (H2-TPR) techniques. High activity was obtained over the catalyst with 9 wt-% Fe content, over which CO conversion and the selectivity of C2=–C4= reached 91.36% and 58.48%, respectively. With the increase of Fe content, both the conversion and the selectivity were improved within a certain range and then decreased. The results show that the surface area of the catalyst played an important role in the catalytic reaction. With the increase of Fe loading, the interaction action between Fe and Mn was enhanced and FeMn solid solution was formed. 相似文献
998.
999.
研究了Cu-25Ni-25Ag合金在600℃和700℃空气中的氧化,合金由富Ag的α相与Cu-Ni固溶体β相组成,氧化速率大致服从抛物线规律,除短时间的加速氧化外,随着氧化的进行氧化速率逐渐减小,尽管存在Ag和Ni,但合金成膜速率与纯Cu的相近,在不同温度下合金都形成了外层为CuO,内层为Cu2O,NiO和Ag颗粒组成的复杂氧化膜,同时,氧化膜最前沿的Cu-Ni固溶体颗粒仅表面部分氧化,未氧化的内核被连续NiO所包围。 相似文献
1000.
长碳链多胺类系列化合物对铁在含H2S的硫酸溶液中的缓蚀作用 总被引:2,自引:0,他引:2
设计并合成出一系列长碳链多胺类(LCMA)化合物,应用多种电化学测试手段研究了LCMA在酸性H2S体系中的缓蚀作用,结果表明,具有多活性官能团的LCMA分子可平卧吸附于电极表面,以负催化作用显著抑制铁的H2S腐蚀反应;LCMA的高效缓蚀作用与活性能团的结构和碳链长短有关。 相似文献