A B S T R A C TThe antioxidant capacities and total phenolic contents of lipophilic and hydrophilic extracts of 56 commonly consumed vegetables were studied. The resulted showed that antioxidant capacities and total phenolic contents in the lipophilic fraction were higher than those in hydrophilic fraction. The different vegetables had diverse antioxidant capacities. The highest antioxidant capacities and phenolic contents were found in Chinese toon bud, loosestrife, perilla leaf, cowpea, caraway, lotus root, sweet potato leaf, soy bean (green), pepper leaf, ginseng leaf, chives, and broccoli, while the values were very low in marrow squash and eggplant (purple). Furthermore, several phenolic compounds were detected, and chlorogenic acid, gallic acid and galangin were widely found in these vegetables. The results provide support for dietary guidelines as well as epidemiological research.
The development of low-cost, efficient physisorbents is essential for gas adsorption and separation; however, the intrinsic tradeoff between capacity and selectivity, as well as the unavoidable shaping procedures of conventional powder sorbents, greatly limits their practical separation efficiency. Herein, an exceedingly stable iron-containing mordenite zeolite monolith with a pore system of precisely narrowed microchannels was self-assembled using a one-pot template- and binder-free process. Iron-containing mordenite monoliths that could be used directly for industrial application afforded record-high volumetric carbon dioxide uptakes (293 and 219 cubic centimeters of carbon dioxide per cubic centimeter of material at 273 and 298 K, respectively, at 1 bar pressure); excellent size-exclusive molecular sieving of carbon dioxide over argon, nitrogen, and methane; stable recyclability; and good moisture resistance capability. Column breakthrough experiments and process simulation further visualized the high separation efficiency.
An ionic copolymer catalyst with nanopores, large surface area, high ionic density, and superior basicity was prepared via the radical copolymerization of amino-functionalized ionic liquid bromide and divinylbenzene, followed with a hydroxyl exchange for removing bromonium. Evaluated in chemical fixation of CO2 with epoxides into cyclic carbonates in the absence of any solvent and basic additive, the nanoporous copolymer catalyst showed high and stable activity, superior to various control catalysts including the halogen-containing analogue. Further, high yields were obtained over a wide scope of substrates including aliphatic long carbon-chain alkyl epoxides and internal epoxide, even under atmospheric pressure and less than 100 °C for the majority of the substrates. On the basis of in situ Fourier transform infrared (FT-IR) investigation and density functional theory (DFT) calculation for the reaction intermediates, we proposed a possible reaction mechanism accounting for the superior catalytic activity of the ionic copolymer. The specifically prepared ionic copolymer material of this work features highly stable, noncorrosive, and sustainable catalysis and, thus, may be a new possibility for efficient chemical fixation of CO2 since it is an environmentally friendly, metal-free solid catalyst.
Au–Pd nanoalloy in hydrophilic mesoporous poly(ionic liquid) shows high activity for oxidation of 5-hydroxymethylfurfural to 2,5-furandicarboxylic acid with atmospheric O2.
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