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71.
通过对2-甲基-8-(2-吡啶基)苯并呋喃[2,3-B]吡啶辅助配体进行修饰,在吡啶的4号位引入吸电子基团苯基,并对其进行全氘代,同时对5-甲基-2-对甲苯基吡啶主配体的两个甲基进行全氘代,分别合成了两种铱磷光配合物Ⅳ和Ⅳ-d20,采用元素分析、质谱和核磁共振氢谱对其结构进行了表征与确认。利用UV-Vis 光谱、荧光发射光谱(PL)和循环伏安法对其光物理性质及能级结构进行了研究。结果表明:铱配合物的Ⅳ和Ⅳ-d20光致发光光谱发射波长分别为546.85nm和548nm;它们的HOMO和LUMO能级分别为-5.237ev和-2.645ev、-5.082ev和-2.50ev,都是潜在的黄绿色磷光材料。以铱配合物Ⅳ和Ⅳ-d20为客体,制备了结构为ITO/HT:NDP-9(100nm,2%)/HT(130nm)/EB(10nm)/GH:化合物Ⅳ或Ⅳ-d20(40nm,5%)/HB(10nm)/ ET:Liq(35nm,50%)/Liq(10nm)/Al(150nm)的OLED器件,并研究了它们的器件性能。结果表明:铱配合物Ⅳ-d20表现出更优异的器件性能。电流密度为20mA/cm2时,铱配合物Ⅳ-d20的器件发射波长为552nm,CIE 坐标为 (0.422,0.569),电流效率为 87.00cd/A,外量子效率(EQE)高达23.82%。 相似文献
72.
73.
Massimo Nespolo 《Crystallography Reviews》2017,23(4):302-303
Some statements in the review by Liu et al. [Liu Y, Liu Y, Drew GB. Comparison of calculations for interplanar distances in a crystal lattice. Cryst Rev. 2017] are corrected. The role of metric tensor to simplify calculations of interplanar spacings in crystal lattices is emphasized. 相似文献
74.
Kazushige Ishida Yoichi Wada Masahiko Tachibana Nobuyuki Ota Motohiro Aizawa 《Journal of Nuclear Science and Technology》2013,50(11):1071-1082
The effects of water chemistry distribution on the potential of a reference electrode and of the potential distribution on the measured potential should be known qualitatively to obtain accurate electrochemical corrosion potential (ECP) data in BWRs. First, the effects of oxygen on a platinum reference electrode were studied in 553 K pure water containing dissolved hydrogen (DH) concentration of 26–105 μg kg?1 (ppb). The platinum electrode worked in the same way as the theoretical hydrogen electrode under the condition that the molar ratio of DH to dissolved oxygen (DO) was more than 10 and that DO was less than 100 ppb. Second, the effects of potential distribution on the measured potential were studied by using the ECP measurement part without platinum deposition on the surfaces connected to another ECP measurement part with platinum deposition on the surfaces in 553 K pure water containing 100–130 ppb of DH or 100–130 ppb of DH plus 400 ppb of hydrogen peroxide. Measured potentials for each ECP measurement part were in good agreement with literature data for each surface condition. The lead wire connecting point did not affect the measured potential. Potential should be measured at the nearest point from the reference electrode in which case it will be not affected by either the potential distribution or the connection point of the lead wire in pure water. 相似文献
75.
《Journal of Nuclear Science and Technology》2013,50(8):585-588
Chloride ion (foreign ion) effect on the precipitation of thorium or uranium (VI) sulfato, carbonato and oxalato complex ions has been studied. The results are in correlation with the chemical species present in the solution. The precipitation of highly-charged complex ions is affected by chloride ion and the precipitation yield decreases with chloride salt concentration. The precipitation of sulfato complex ion shows only slight dependency on the chloride salt concentration because of the absence of highly-charged sulfato complex ion under the experimental conditions. 相似文献
76.
Bingren Tian Dong Xiao Tingting Hei Rui Ping Shiyao Hua Jiayue Liu 《Polymer International》2020,69(7):597-603
Cyclodextrin is an odorless and tasteless cyclic oligosaccharide widely used in various fields such as food, medicine and the environment. Cyclodextrin can improve solubility and stability, and can mask the bad taste of specific substances. Cyclodextrins and their polymers primarily act by forming complexes in foods, and can be applied in food packing, food analysis, enhancing the properties of antioxidants, antibacterials, for stability and so on. The challenges and opportunities facing this area are reviewed. It is hoped that the review will provide useful information for future applications of cyclodextrin in the food industry. © 2020 Society of Chemical Industry 相似文献
77.
Hyun Shin Yeon Hee Ha Hyun‐Gu Kim Ran Kim Soon‐Ki Kwon Yun‐Hi Kim Jang‐Joo Kim 《Advanced materials (Deerfield Beach, Fla.)》2019,31(21)
Deep‐blue emitting Iridium (Ir) complexes with horizontally oriented emitting dipoles are newly designed and synthesized through engineering of the ancillary ligand, where 2′,6′‐difluoro‐4‐(trimethylsilyl)‐2,3′‐bipyridine (dfpysipy) is used as the main ligand. Introduction of a trimethylsilyl group at the pyridine and a nitrogen at the difluoropyrido group increases the bandgap of the emitter, resulting in deep‐blue emission. Addition of a methyl group (mpic) to a picolinate (pic) ancillary ligand or replacement of an acetate structure of pic with a perfluoromethyl‐triazole structure (fptz) increases the horizontal component of the emitting dipoles in sequence of mpic (86%) > fptz (77%) > pic (74%). The organic light‐emitting diode (OLED) using the Ir complex with the mpic ancillary ligand shows the highest external quantum efficiency (31.9%) among the reported blue OLEDs with a y‐coordinate value lower than 0.2 in the 1931 Commission Internationale de L'Eclairage (CIE) chromaticity diagram. 相似文献
78.
Eu(1-X)LnX(TTA)3Phen荧光配合物的原位合成和光固化荧光防伪油墨的性能研究 总被引:1,自引:0,他引:1
在EA基质中,合成了Eu(1-X)LnX(TTA)3Phen配合物(Ln=G d、Y和L a,TTA=噻吩甲酰三氟丙酮,Phen=1,10邻-菲咯啉,X=掺杂元素的摩尔分数)。红外光谱的分析表明,配合物的吸收峰被EA(EA=双酚A-环氧丙烯酸酯)基质掩盖,表现为EA的特征吸收;荧光激发光谱、荧光发射光谱的研究表明,在EA基质中Eu(1-X)LnX(TTA)3Phen配合物已经形成,并且表现出强的铕离子特征荧光。荧光体系经固化后的荧光强度明显低于固化前的荧光强度,并讨论了荧光猝灭机理。 相似文献
79.
构筑手性金属有机骨架的方法及其在不对称催化中的应用 总被引:1,自引:0,他引:1
手性金属有机骨架(MOF)具有独特的结构、不对称催化和手性拆分等性能,引起了催化学者的极大重视.系统地介绍了国内外有关手性MOF的合成方法,即:①非手性物质在晶体生长过程中自组装;②使用手性化合物来诱导合成;③通过手性有机基团与金属离子配位将手性成分嵌入金属有机骨架;④表面修饰的方法,第3种方法是最常用的合成手性MOF的方法.重点阐述了近年来手性MOF在不对称催化领域的最新研究成果,希望能为手性MOF研究者设计、合成更优良的手性MOF催化剂提供参考.未来手性MOF催化的主要目标在于合成性能更加高效、稳定的新型手性MOF催化剂,并应用于大规模工业生产中,在温和条件下实现较高的转化数和对映体选择性. 相似文献
80.
Elzbieta Radzyminska-Lenarcik 《溶剂提取与离子交换》2013,31(5):636-652
Abstract The formation of Cu(II) complexes with 1-alkyl-4-methylimidazoles (where alkyl = butyl, pentyl, hexyl, heptyl, octyl, nonyl, and decyl) has been studied by using the liquid-liquid partition method at 25°C and a fixed ionic strength of the aqueous phase (I = 0.5; (HL)NO3, KNO3). 2-Ethylhexanol, dichloromethane, chloroform, p-xylene, and toluene were used as a solvent. Stability constants, βn, of the complexes in aqueous solution were determined as well as their partition ratios between the organic and aqueous phase. Under the influence of the steric effect, the methyl group in position 4 as well as the length of the alkyl group in position 1 of the ligands and electron-donating properties of solvents, both the polyhedral structure and the co-ordination numbers of the Cu(II) complexes are changed, thus resulting in an increase in the solvent/water partition ratios, Pn, of the complexes and lowering of the pH1/2 of the extraction. 相似文献