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62.
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CommentDuringinvestigationsonvariousmetalcomplexeswithH鄄Norf[1,2],complexationwithBiwasinvestigated.Fig.1showsthestructureofthefirstBi髥complexcontainingtheantibacterialdrugNorfloxacin○,[Bi2Cl10(H2鄄Norf)4(H2O)8].Thisisanioniccompoundcompris鄄ingfour[H2 相似文献
65.
Wei L Yang B Yang R Huang C Wang J Shan X Sheng L Zhang Y Qi F Lam CS Li WK 《The journal of physical chemistry. A》2005,109(19):4231-4241
The photoionization and dissociative photoionization of acetone have been studied at the photon energy range of 8-20 eV. Photoionization efficiency spectra for ions CH3COCH3+, CH3+, C2H3+, C3H3+, C3H5+, CH(2-)CO+, CH3CO+, C3H4O+, and CH3COCH2+ have been measured. In addition, the energetics of the dissociative photoionization has been examined by ab initio Gaussian-3 (G3) calculations. The computational results are useful in establishing the dissociation channels near the ionization thresholds. With the help of G3 results, the dissociation channels for the formation of the fragment ions CH3CO+, CH2CO+, CH3+, C3H3+, and CH3COCH2+ have been established. The G3 results are in fair to excellent agreement with the experimental data. 相似文献
66.
ADSORPTION OF 2,4-DICHLOROBENZOXYACETIC ACID ONTO HYPERCROSSLINKED RESIN MODIFIED BY PHENOLIC HYDROXYL GROUP (AM-1) 总被引:2,自引:0,他引:2
INTRODUCTIONAdsorption has been considered to be the best available technology for removing organics from water in the USSafe Drinking Water Act[1]. Due to many drawbacks of activated carbon[2-7], the most widely used adsorbent,hypercrosslinked polymeric adsorbents developed by Tsyurupa and Davankov[8] have been increasingly viewedas an alternative to activated carbon for selective removal of specific organic substances from contaminatedwater[9-12], and series of researches have been do… 相似文献
67.
Huang F Hou L Wu H Wang X Shen H Cao W Yang W Cao Y 《Journal of the American Chemical Society》2004,126(31):9845-9853
A series of aminoalkyl-substituted polyfluorene copolymers with benzothiadiazole (BTDZ) of different content were synthesized by Suzuki coupling reaction, and their quaternized ammonium polyelectrolyte derivatives were obtained through a postpolymerization treatment on the terminal amino groups. Copolymers are soluble in environmentally friendlier solvents, such as alcohols. It was found that the efficient energy transfer occurs by exciton trapping on the narrow band gap BTDZ site under UV illumination. Only 1% of BTDZ content is needed to completely quench a fluorene emission for both the neutral and the quaternized copolymers in the neat film. Absolute PL efficiencies of copolymer films were greatly enhanced as a result of the suppression of excimer formation. Light-emitting devices fabricated from these copolymers show high external quantum efficiencies over 3% and 1% for the neutral precursor and the quaternized copolymers, respectively, with high work function metals such as Al as a cathode. To the best of our knowledge, this is the first report on an electroluminescent polymer which bears the high EL efficiency, the electron-injection ability from high work function metals, and the solubility in environment-friendly solvents at the same time. These features make them a promising candidate for the next generation of light-emitting copolymers in PLED flat panel display application. 相似文献
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A Minor New Flavone from Scutellaria baicalensis Georgi 总被引:1,自引:0,他引:1
A new flavone,6,2′-dihydroxy-5,7,8,6′-tetramethoxyflavone,was isolated from the roots of Scutellaria baicalensis. Its structure was established on the basis of spectral evidences. 相似文献
70.
GangWEI HaiYahHUANG RongChunXIONG 《中国化学快报》2003,14(8):877-880
TiO2 nanoparticles were synthesized by using micro-reactors. The shape and size of the nanoparticles produced from the original micro-reactors and the five times recycled micro-reactorsmother liquor were investigated on transmission electron microscopy (TEM) by using the original sample, freeze prepared sample, and dyeing treated sample, respectively. UV-VIS spectrometry was used to study the growth process of TiO2 nanoparticles in main reactors. The results showed that micro-reactors with nanometer magnitude had spherical or oval structures, and could restore to their original structure after they were destroyed. The products prepared in the original micro-reactors were similar to that in the micro-reactors recycled for many times, suggesting that the micro-reactors had memory function. 相似文献