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84.
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
85.
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
86.
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
87.
Vélez Carlos A. Soto-Pérez Joesene J. Corchado-García Juan Larios Eduardo Fulvio Pasquale F. Echegoyen Luis Cabrera Carlos R. 《Journal of Solid State Electrochemistry》2021,25(1):207-217
Journal of Solid State Electrochemistry - The glucose oxidation reaction, at Pd on unsupported carbon nano-onions (Pd/CNOs), has been studied by using physical and electrochemical characterization... 相似文献
88.
Fulvio PF Lee JS Mayes RT Wang X Mahurin SM Dai S 《Physical chemistry chemical physics : PCCP》2011,13(30):13486-13491
A novel strategy for tailoring the adsorption and structural properties of ionic liquid derived carbons has been developed. By changing the carbonization temperature and ratios of ionic liquids (ILs) containing a cross-linkable anion, such as 1-butyl-3-methylimidazolium tricyanomethanide [BMIm][C(CN)(3)] and 1-ethyl-3-methylimidazolium tetracyanoborate [EMIm][B(CN)(4)], boron and nitrogen-rich carbons with slit-like pores and specific surface areas exceeding 500 m(2) g(-1) have been prepared. Furthermore, the nitrogen-rich carbons exhibit high adsorption capacity for CO(2) adsorption and selectivity for CO(2)/N(2) separation. 相似文献
89.
Pietro Franceschi Domenico Masuero Urska Vrhovsek Fulvio Mattivi Ron Wehrens 《Journal of Chemometrics》2012,26(1-2):16-24
The development and the validation of innovative approaches for biomarker selection are of paramount importance in many ‐omics technologies. Unfortunately, the actual testing of new methods on real data is difficult, because in real data sets, one can never be sure about the “true” biomarkers. In this paper, we present a publicly available metabolomic ultra performance liquid chromatography–mass spectrometry spike‐in data set for apples. The data set consists of 10 control samples and three spiked sets of the same size, where naturally occurring compounds are added in different concentrations. In this sense, the data set can serve as a test bed to assess the performance of new algorithms and compare them with previously published results. We illustrate some of the possibilities provided by this spike‐in data set by comparing the performance of two popular biomarker‐selection methods, the univariate t‐test and the multivariate variable importance in projection. To promote a widespread use of the data, raw data files as well as preprocessed peak lists are made available. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
90.
Fulvio Mattivi Bruno Fedrizzi Alberto Zenato Paolo Tiefenthaler Silvano Tempesta Daniele Perenzoni Paolo Cantarella Federico Simeoni Urska Vrhovsek 《Analytica chimica acta》2012
This paper presents methods for the definition of important analytical tools, such as the development of sensitive and rapid methods for analysing reduced and oxidised glutathione (GSH and GSSG), hydroxycinnamic acids (HCA), bound thiols (GSH-3MH and Cys-3MH) and free thiols (3MH and 3MHA), and their first application to evaluate the effect of reductive winemaking on the composition of Lugana juices and wines. 相似文献