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51.
Synthesis and Characterization of Novel Orange-emitting Iridium(Ⅲ) Complexes with Diphenylquinoline Ligands Containing Fluorinated Substituent 总被引:1,自引:0,他引:1
Xiao Wei ZHANG Chu Luo YANG Zhong An LI Lin Na ZHU Jin Gui QIN Jia GAO Dong Ge MA 《中国化学快报》2006,17(3):411-414
Three new cyclometalated iridium(m) complexes based on ligands of diphenylquinoline with fluorinated subsfituents were prepared, and characterized by elemental analysis (EA), ^1H NMR, and mass spectroscopy (MS). The photophysical and electrophosphorescent properties of the complexes were briefly discussed. 相似文献
52.
杂多酸的固载化─关于制备负载型酸催化剂的一般原理 总被引:10,自引:0,他引:10
杂多酸同时具有酸和氧化-还原的催化特性,有着很广泛的应用前景.这类化合物在一系列精细合成中取代硫酸作为催化剂以满足环保的要求,显示出了很大的潜力.杂多酸固载化后,不仅能在液相氧化和酸催化反应中把催化剂从反应介质中很方便地分离出来,而且还为这类均相催化反应的多相化,甚至利用催化蒸馏新工艺等创造了应有的条件,可以使生产工艺大大简化,获得更广泛的应用.本文以很好表征过的多种孔性材料,包括氧化物,如Al_2O_3、SiO_2、TiO_2、硅藻土、膨润土和来源不同的活性炭为载体,考察了负载杂多酸催化剂的催化活性.在大量前期工作的基础上,通过总结载体对固载杂多酸催化活性的影响等,探讨载体的内在性质在杂多酸固载、吸附和催化反应中的作用本质,为由吸附法制备各种负载型固体酸催化剂在液相中的应用提供可资参考的模型. 相似文献
53.
The ultraviolet photolysis of low concentrations of CH(2)XI (X = Cl, Br, I) were investigated in water and saltwater solutions by photochemistry and picosecond time-resolved resonance Raman spectroscopy. Photolysis in both kinds of solutions formed mostly CH(2)(OH)(2) and HI and HX products. However, photolysis of the CH(2)XI molecules in saltwater resulted in production of some CH(2)XCl products not observed in aqueous solutions without salt present. The appearance of these new products in saltwater solutions is accompanied by a decrease in the amount of CH(2)(OH)(2), HI, and HX products compared to photolysis in aqueous solutions without salt present. The possible implications for photolysis of CH(2)XI and other polyhalomethanes in seawater and other salt aqueous environments compared to nonsaltwater solvated environments is briefly discussed. 相似文献
54.
A rapid method for the derivatization of phenolic antioxidants using microwave irradiation has been developed. Six antioxidatively active phenolic components of wines and fruits, namely gallic acid, gentisic acid, vanillic acid, caffeic acid, ferulic acid and p-coumaric acid were used in the model study. The solution of phenolic acids was evaporated to dryness on a rotary evaporator followed by further drying under microwave irradiation (600 W, 30 s). The resultant residue was dissolved in pyridene and treated with bis(trimethylsilyl)acetamide while irradiated by microwave using high power for 30 s. Controlled reaction was carried out employing bis(trimethylsilyl)trifluoroacetamide under conventional heating for 30 min. The trimethylsilyl derivatives were identified and quantified on a gas chromatography/mass selective detector. The mass spectral fragmentation patterns of the derivatives obtained by microwave irradiation were identical to those prepared by heating. The yields of microwave-assisted silylation were comparable to those from conventional heating. The rsd were less than 8% for six replicates. The linearity in wine matrix was nearly perfect. This method is a useful protocol to examine the phenolic constituents in wines and agricultural products. 相似文献
55.
使用TPR和H2-TPD技术对镍铝系催化剂的还原和氢脱附性能进行了研究,并与其催化性能相关联。结果发现,镍铝系催化剂的氢脱附能力与其催化性能之间有一定联系,脱附氢能力越强,催化剂的甲烷部分氧化反应性能就越好,但催化性能与还原性能无直接关联。 相似文献
56.
57.
Jia Rui Wang Chu Ting Yang Lei Liu Qing Xiang Guo Department of Chemistry University of Science Technology of China Hefei China 《中国化学快报》2007,18(2):133-136
Aerobic oxidation of electron-rich benzylic and phenyl allylic alcohols was achieved with high yields with only 0.1 mol.% of Pd(OAc)2 catalyst in the absence of any ligand. This procedure was expected to be valuable for realistic industrial-scale applications from both economic as well as environmental points of view. 相似文献
58.
59.
A high-performance capillary electrophoretic (CE) method with electrochemical detection (ED) has been developed for determination of the pharmacologically active flavonoids in Ginkgo biloba L. and phytopharmaceuticals containing its extract. Epicatechin, catechin, rutin, apigenin, luteolin, and quercetin are important flavonoids in this plant. Operated in a wall-jet configuration, a 300 micro m diameter carbon-disk electrode was used as working electrode with good response to the six analytes at +1000 mV (relative to the SCE). Under the optimum conditions, the analytes were separated within 22 min in a borax buffer (pH 9.0). Excellent linearity was obtained over two orders of magnitude and detection limits (S/N=3) ranged from 1.4 x 10(-7) to 5.0 x 10(-7) g mL(-1) for all six analytes. The method was successfully used for assay of Ginkgo biloba L. and its phytopharmaceuticals after a relatively simple extraction procedure; the results obtained were satisfactory. 相似文献
60.