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排序方式: 共有241条查询结果,搜索用时 31 毫秒
81.
Dr. Chien‐Yang Chiu Dr. Hengbin Wang Dr. Fulvio G. Brunetti Prof. Fred Wudl Prof. Craig J. Hawker 《Angewandte Chemie (International ed. in English)》2014,53(15):3996-4000
Here we report a novel twisted monomer based on a distorted C?C double bond for low bandgap conjugated copolymers. This new building block provides several unique characteristics when compared to classical planar systems such as high solubility, electron accepting ability, and isomeric tunability. The resulting copolymers exhibit broad absorption spanning both visible and near‐infrared regions leading to promising solar cell performance. 相似文献
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Michael Cowling Anna Maria Mantero Fulvio Ricci 《Rendiconti del Circolo Matematico di Palermo》1982,31(2):145-158
Si ottengono delle stime per il nucleo di Gauss-Weierstrass su gruppi di Lie compatti e se ne indicano alcune applicazioni. 相似文献
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Brunetti FG Herrero MA Muñoz Jde M Díaz-Ortiz A Alfonsi J Meneghetti M Prato M Vázquez E 《Journal of the American Chemical Society》2008,130(25):8094-8100
We describe a new synthetic strategy to produce multifunctionalized carbon nanotubes using a combination of two different addition reactions, the 1,3-dipolar cycloaddition of azomethine ylides and the addition of diazonium salts, both via a simple and fast microwave-induced method. The presence of multifunctionality on the SWNTs has been confirmed using the most useful techniques for the characterization of carbon nanotubes. The doubly functionalized SWNTs can be considered potentially useful for many interesting applications. 相似文献
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The one-pot synthesis of alumina-supported metal oxides via self-assembly of a metal precursor and aluminum isopropoxide in the presence of triblock copolymer (as a structure directing agent) is described in detail for nickel oxide. The resulting mesoporous mixed metal oxides possess p6 mm hexagonal symmetry, well-developed mesoporosity, relatively high BET surface area, large pore widths, and crystalline pore walls. In comparison to pure alumina, nickel aluminum oxide samples exhibited larger mesopores and improved thermal stability. Also, long-range ordering of the aforementioned samples was observed for nickel molar percentages as high as 20%. The generality of the recipe used for the synthesis of mesoporous nickel aluminum oxide was demonstrated by preparation of other alumina-supported metal oxides such as MgO, CaO, TiO 2, and Cr 2O 3. This method represents an important step toward the facile and reproducible synthesis of ordered mesoporous alumina-supported materials for various applications where large and accessible pores with high loading of catalytically active metal oxides are needed. 相似文献
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In this work, a methodological approach is reported, aimed at assessing the electrochemical response of some model gluco-oligosaccharides (dextrans). Such strategy is based on the complementary use of both anion-exchange chromatography with pulsed amperometric detection (HPAEC-PAD) and capillary zone electrophoresis coupled with UV detection (CZE-UV). Unlike HPAEC-PAD, CZE-UV required derivatization with a chromophoric dye (i.e., 8-aminonaphtalene-1,3,6-trisulphonic acid, ANTS) to enhance UV response and separation selectivity. From the comparison between chromophore response and PAD signal, the reliability of HPAEC-PAD for quantitative evaluation of dextran mixtures containing mainly oligomers with polymerization degree (DP) up to 18 could be proved, due to the fairly constant molar response. For higher DPs (up to 41), a maximum in the trend of the molar responses was observed followed by a steep decrease for DPs higher than about 30-35; indeed, an underestimation of weight-average molecular weight of dextran mixtures containing such oligomers was noticed. 相似文献