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Reaction solutions of selectfluor (1) with triphenylethylene (4a) and tetraphenylethylene (4b) were monitored by ESI-MS and ESI-MS/MS. Detection and characterization of the key radical cationic intermediates 5a.+ and 5b.+) fully supports the SET mechanism in electrophilic fluorination as depicted above. [reaction: see text] 相似文献
53.
[structure: see text] Remarkable UV OLED devices using novel spiro-configured bifluorenes as UV emitters have been successfully achieved with external quantum efficiencies up to 2.6-3.1% and emission wavelengths as short as 370 nm. In addition, these large-gap materials have been shown to be effective hosts for red phosphorescent emitters in phosphorescent OLEDs. This result represents the first example that pure hydrocarbon molecules can serve as an efficient host for red electrophosphorescence devices. 相似文献
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Based on gaseous compound introduction as 1-phenyl-3-methyl-4-benzoylpyrazolone[5](PMBP) chelate of aluminum by electrothermal vaporization in ICP-AES, a method for determination of trace aluminum was developed. Trace aluminum was vaporized at temperature of 1000 degrees C, and the vaporization behavior of aluminum chelate was detailedly investigated. Under the optimum conditions, the detection limit of aluminum was 0.6 ng ml(-1), and the relative standard deviation for 0.1 mug ml(-1) aluminum was 4.7% (n=8). The proposed method was applied to the determination of trace aluminum in rice flour reference materials, and the results well agreed with the reference values. 相似文献
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Chen-Xi Zhang Zhi-Liang Liu Dai-Zheng Liao Zong-Hui Jiang Shi-Ping Yan 《Journal of Molecular Structure》2003,650(1-3):21-26
A novel complex [Cu(NIT2Py)(PDA)(H2O)]·(CH3OH)(H2O) has been synthesized and structurally characterized by X-ray diffraction methods. It crystallizes in the monoclinic space group P2(1)/c. The structure consists of [Cu(NIT2Py)(PDA)(H2O)] moiety, one solvent methanol molecule and one water molecule. The copper(II) ion is in a distorted octahedral environment: one nitrogen atom and one oxygen atom from the NIT2Py, one nitrogen atom from the PDA (2,6-pyridine dicarboxylic acid) and one oxygen atom from the aqueous in the basal plane; two oxygen atoms from the PDA in the axial position. The units of [Cu(NIT2Py)(PDA)(H2O)] were connected as one dimension chain by the intermolecular hydrogen bonds. The complex exhibits intramolecular antiferromagnetic interactions between the Cu(II) ion and the NIT2Py. 相似文献
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Qing‐Lun Wang Mao Liang Dai‐Zheng Liao Shi‐Ping Yan Zong‐Hui Jiang Peng Cheng 《无机化学与普通化学杂志》2004,630(4):613-616
A unique neodymium(III) complex, {[Nd(BTC)(H2O)4] · H2O}n (BTC = 1, 3, 5‐benzenetricarboxylate), was obtained from the reaction between Nd(ClO4)3 · xH2O and Na3BTC. Coordination bonds, hydrogen bonds, and π‐π stacking form a supramolecular structure with a novel, two‐dimensional framework. The temperature‐dependent magnetic susceptibilities were analyzed by the Curie‐Weiss law; the following values were found C = 1.32, θ = —18.3 K, respectively. 相似文献
60.
负载稀土型酸活化膨润土的酯化催化活性 总被引:7,自引:0,他引:7
负载稀土型酸活化膨润土的酯化催化活性李永绣,冯天泽,胡平贵,何小彬,辜子英,廖荣辉(南昌大学化学系南昌330047)关键词稀土,膨润土,催化酯化可用稀土、膨润土单独作酯化催化剂,但活性不高[1~3]。本文将稀土用离子交换的方法负载到酸活化膨润土中,寻... 相似文献