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Effect of Cu-ZSM-5 catalysts with different CuO particle size on selective catalytic oxidation of N,N-Dimethylformamide

《环境科学与工程前沿（英文）》 2022年第16卷第10期 doi: 10.1007/s11783-022-1557-0

摘要：

● A series of Cu-ZSM-5 catalysts were tested for DMF selective catalytic oxidation.

关键词： N N-Dimethylformamide Selective catalytic oxidation Cu-ZSM-5 CuO particle size

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Synthesis of p -substituted tetraphenylporphyrins and corresponding ferric complexes with mixed-solvents method

Zhicheng SUN, Yuanbin SHE, Rugang ZHONG,

《化学科学与工程前沿（英文）》 2009年第3卷第4期页码 457-461 doi: 10.1007/s11705-009-0169-6

摘要： By using mixed-solvents method, five kinds of -substituted tetraphenylporphyrin compounds [T(-R)PPH, R=NO, Cl, CH, OCH, OH] were synthesized by the condensation of -substituted benzaldehyde with pyrrole in mixed solvents (propionic acid, acetic acid and nitrobenzene), and corresponding ferric complexes [T(-R)PPFeCl] were synthesized in dimethylformamide. The above free base porphyrins were obtained in 30%–50% yields, metalation yields were up to 90% and total yields of ferric complexes were 27%–50%. Effects of reactive conditions, solvents and oxidants on yields of free base porphyrins were investigated and the relevant mechanism was discussed. Structures of the above porphyrin complexes were characterized by ultraviolet-visible (UV-Vis), infrared (IR) and far infrared (FIR) spectroscopy.

关键词： -substituted tetraphenylporphyrin condensation -substituted benzaldehyde dimethylformamide metalation

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Hyperbranched azo polyurethane synthesized through A + B scheme

CHE Pengchao, HE Yaning, WANG Xiaogong

《化学科学与工程前沿（英文）》 2008年第2卷第1期页码 123-126 doi: 10.1007/s11705-007-0078-5

摘要： A hyperbranched azo polyurethane was synthesized by one-step polymerization of an A type monomer diphenylmethane-4,4′-diisocyanate and a B type monomer 4-(N,N′-bis(2-hydroxyethyl))amino-2′-hydroxyethoxyl-4′-nitro-azobenzene. The azo polymer was characterized by H nuclear magnetic resonance (NMR), ultraviolet-visible (UV-Vis) spectrum and thermal analysis. The of the polymer in dimethylformamide (DMF) solution is 488 nm. The number average molecular weight (M) determined by GPC is 9,300 with a polydispersion index 1.9. The glass transition temperature () of the polymer is 131°C observed from DSC thermogram. The results show that the azo polyurethane has been successfully synthesized through this scheme. Surface-relief-gratings (SRGs) were fabricated on the polymer film after being irradiated by interference pattern of Ar laser beams for 1,000 s. The surface modulation depth and the grating space period measured by AMF are 67 and 770 nm, respectively.

关键词： dimethylformamide one-step polymerization polyurethane 2-hydroxyethyl diphenylmethane-4 4′-diisocyanate